Nano Research
A Facile Synthesis of Hierarchical Sn3O4 Nanostructures in an Acidic Aqueous
Solution and Their Strong Visible Light-Driven Photocatalytic Activity
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A Facile Synthesis of Hierarchical Sn 3O 4 Nanostructures in an Acidic Aqueous Solution
and
Their
Strong
Visible
Light-Driven Photocatalytic Activity Hui Song a , Su-Young a,b , and Gun Young Jung a ,*
a School of Materials Science and Engineering,
Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea.
b Carbon
Covergence Materials Research
Center, Institute of Advanced Composite Materials Korea Institute of Science and Technology (KIST), Jeollabuk-do, South Korea
Hierarchical Sn 3O 4 Nanosphere covered with single crystalline nanoplates is hydrothermally transformed from SnO nanoparticles in strong acidic ambient condition. The narrow band gap of 2.25 eV renders it to absorb the intense energy of visible wavelengths from the Sun, generating more electron-hole pairs. The
reaction of the generated holes with the hydroxyl groups in aqueous solution can form the hydroxyl radicals, which can effectively attack the organic pollutants owing to the high oxidation potential of the radicals.
Gun Young Jung, https://www.doczj.com/doc/ee8350052.html,
Manuscript
Click here to download Manuscript: Hierarchical Sn3O4 nanostructure.docx Click here to view linked References
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A Facile Synthesis of Hierarchical Sn 3O 4 Nanostructure in an Acidic Aqueous Solution and Their Strong Visible Light-Driven Photocatalytic Activity
Hui Song a , Su-Young Son a,b and G. Y. Jung a ,* ( )
a School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, South
Korea.
b Carbon Covergence Materials Research Center, Institute of Advanced Composite Materials Korea Institute of Science and Technology (KIST), Jeollabuk-do, South Korea
Received: day month year / Revised: day month year / Accepted: day month year (automatically inserted by the publisher) ? Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2011
ABSTRACT
A hierarchical Sn 3O 4 nanospheres were synthesized via hydrothermal reaction under strong acidic ambient condition. The morphology of Sn 3O 4 was varied with decreasing pH; the prickly Sn 3O 4 nanosphere was changed into the Sn 3O 4 nanosphere covered with single crystalline nanoplates with a high surface-to-volume of ca. 55.05 m 2g -1 and a band gap of ca. 2.25 eV . A small amount (0.05 g) of such hierarchical Sn 3O 4 nanostructures completely decomposed 30 % methyl orange (MO) solution in 100 ml deionized water in 15 min under one-Sun condition (UV + Vis. light), The Sn 3O 4 photocatalyst exhibited a fast decomposition rate of 1.73 x 10-1 min -1, which is 90.86 % enhancement compared to that of the commercially available P25 photocatalyst. The high photocatalytic activity of the hierarchical Sn 3O 4 nanostructure was attributed to its ability to absorb visible light and its high surface-to-volume area.
KEYWORDS
Sn 3O 4, Hierarchical structure, Hydrothermal, Morphology engineering, Photocatalyst
1. Introduction
Tin oxide has several advantages of controllable size or shape via the simple hydrothermal method,[1]
excellent
optical
and
electrical
properties (transparency at wave-lengths of 300 ~ 800 nm and a low electronic resistivity of 8.6 x 10-5 ?□-1), its non-toxicity[2] and so on. With these merits, it has been utilized in various fields such as gas
sensors,[3,4]
lithium
ion
batteries,[5]
dye-sensitized solar cells[6] and photocatalysts.[7-9] Regarding its use as a photocatalyst, tin oxide has a strong resistance against acidic/alkali solutions and exhibits a good photocatalytic activity without generating secondary pollutions under irradiation with ultraviolet (UV) light.[8,9] However, there are few works on solely using the tin oxides under irradiation with visible light due to its wide band gap. Therefore, co-catalysts with a narrow energy
Nano Res ————————————
Address correspondence to gyjung@gist.ac.kr 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61
band gap, such as CdS[10], Ru(bpy)32+[11] and Pt[12], have been introduced to enhance the photocatalytic activity of tin oxide under irradiation with visible light. However, as the cost of co-catalysts is expensive, the development of photo-catalytic materials to generate electron-hole pairs under visible light is necessary to effectively utilize the sun light.
Unlike the SnO2as a photocatalyst, Sn3O4has been used as a visible light-driven photocatalyst because it has experimentally shown to absorb light at visible wave-lengths.[13-15] Therefore, the pollution decomposition efficiency of the Sn3O4 photocatalysts is higher than that of SnO2 under the Sun.[13] However, studies on the Sn3O4have just begun, including investigations into its growth mechanism,[16-18] crystal structure and theoretical properties.[19,20]
Sn3O4was formed as one of intermediate tin oxides (i.e., Sn3O4, Sn2O3and Sn5O6) during the disproportiona-tion reaction of Tin(II) oxide (SnO).[21] Sn3O4was mainly generated by dry chemical methods including carbothermal evaporation,[15] thermal decomposition of SnO,[22] carbothermal reduction.[23] Vilasi et. al reported that Sn3O4coexisted as a transition form at the process temperature range of 400-500 o C during the phase transformation from SnO to SnO2.[24] However, only a small quantity of Sn3O4was obtained. Indeed, SnO2was the major product in the reaction, which was thermodynamically more stable than Sn3O4during the oxidation of Sn2+at high temperatures.
For this reason, hydrothermal methods were used to generate the Sn3O4at temperatures below 200 o C without the production of unwanted SnO2.[25,26] Li et. al synthesized hierarchical Sn3O4 structures (diameter: ~ 1 μm) at 180 o C hydrothermally at pH 3 in an autoclave Teflon vessel, which made it difficult to adjust the pH during the hydrothermal processing for controlling the morphology. They showed that the hierarchical Sn3O4structure had the highest pollution decomposition rate among the photocatalysts such as SnO, SnO2 and N-doped TiO2.[13] However, only 10 ppm concentration of methyl orange (MO) in 80 ml solution was decomposed in 20 min by photocatalytic reaction of 0.04 g Sn3O4.
Herein, we propose a facile hydrothermal method in a 3-neck round flask to fabricate hierarchical Sn3O4nanospheres covered with single-crystalline nanoplates at a temperature below 100 o C. By adjusting the pH of nutrient solution during the process, the morphology and phase transformation of SnO into the Sn3O4 nanostructure can be controlled. The generated hierarchical Sn3O4nanostructure has a low band gap and is therefore capable of absorbing visible light in addition to its inherited UV light absorption. Moreover, compared with the commercially available TiO2(Degussa, P25), the synthesized hierarchical Sn3O4nanostructure exhibits much more effective and faster photo-decomposition of MO under one-Sun condition (i.e., Air Mass 1.5, 100 mWcm-2).
2. Experimental Section
2.1 Synthesis of hierarchical Sn3O4 nanostructure
1.23 g of tin oxalate (Sn(C2O4), M = 206.78 gmol-1) was dissolved in 250 ml deionized (DI) water with stirring for 30 min at room temperature. When the temperature reached 70 o C, black precipitates of SnO appeared. Then, the pH value (pH = 2, 3, 4 and 5) of the nutrient solution was adjusted by adding 0.5 M hydrochloric acid (HCl, M = 40.06 gmol-1, 37 %) slowly to the solution having the black precipitate while continuously stirring for 3 hrs at 95 o C. The color of precipitate was changed from black to yellow. After completing the hydrothermal reaction, the precipitate was collected by centrifugation and then washed with DI water. Finally, the product was dried inside a common laboratory oven at 35 o C for 1 day.
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2.2 Characterization of properties
The crystallographic information of hierarchical Sn3O4nanostructure was analyzed by X-ray diffraction (XRD) using Cu K-alpha X-ray radiation (40 kV, 100 mA, Rigaku D/max-2400) and
Raman spectroscopy with a 514 nm laser beam (Horiba). The morphology of sample was observed by scanning electron microscopy (SEM, FE-SEM, JEOL 2010 F) and high resolution transmission electron microscopy (HRTEM, JEM-2100), operated at an accelerating voltage of 200 kV. The specific surface area was measured by the Brunauer-Emmett-Teller (BET) method using nanoporosity surface area analyzer (nanoPOROSITY-XQ, Mirae Scientific Instruments Inc.). UV-Vis. spectrometer
(AvaSpec-ULS2048L-USB2 Spectrometer, Jinyoung tech Inc.) was used to analyze the absorbance of the hierarchical Sn3O4nanostructure and the decomposition of MO solution. Photocatalytic activity was characterized under illumination of an AM 1.5 simulated sunlight source (SANEI solar simulator, Class A) with a power density of 100 ± 2.5 mW cm-2.
2.3 Photocatalytic activity
0.05 g of as-produced catalysts of SnO, Sn3O4and commercially available P25 (TiO2, Degusa) were added into the 30% MO solution in 100 ml DI water. Prior to irradiation, the suspension was violently stirred in the dark for 30 min to saturate the solution with O2. The suspension was irradiated with the light (UV + visible) from a solar simulator. At given time intervals (15, 30, 45 and 60 min), a 3 ml aliquot was extracted and filtered to remove the photocatalytic powder. The filtered solution was analyzed by a UV-Vis. spectrometer to measure the MO contents (Maximum absorption band, λ = 485 nm).
3. Results and discussion
3.1. The effect of pH on the formation of
hierarchical Sn3O4 nanostructure
The hierarchical Sn3O4nanostructures were synthesized by hydrothermal reaction at 95 o C. Tin oxalate, Sn(C2O4), was used as the tin ions source. Unlike the most commonly used tin salts such as tin dichloride (SnCl2) and tin tetrachloride (SnCl4), the Sn(C2O4) can easily offer abundant tin(II) ions (Sn2+) in the nutrient solution because it can be dissociated easily at a low temperature due to a relatively weak electro-static attraction between the pure metal ion (Sn2+) and the organic chelating reagent (C2O4-).[6] Thus, SnO was easily synthesized at first by using the Sn(C2O4) as a starting material at a low temperature. Then, in an acidic condition the SnO was easily dissolved and changed into a tin complex ion (Sn3(OH)42+). Finally, the Sn3O4 nanostructures were formed by dehydration of the Sn3(OH)42+.[27]
When the temperature of nutrient solution reached 70 o C, the color of the precipitate changed from white to black, indicating the formation of SnO, and remained black until 95 o C. However, the color of the precipitate became yellow at 95 o C after adding a hydrochloric acid solution, indicating that some changes occurred to the SnO. The morphology and phase transformation of the Figure 1.XRD patterns of the precipitates synthesized at different pH values; (a) SnO, (b) pH=5, (c) pH=4, (d) pH=3, and (e) pH=2. (●: SnO, ■: Sn3O4)
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脱水
products were examined at various pH values of the solution, which was controlled by varying the amount of added hydrochloric acid. After
completing
the
hydrothermal
reaction,
the
precipitate was collected by centrifugation and then dried to analyze the structure and its photocatalytic ability.
The crystallographic structure of the hierarchical Sn 3O 4 nanostructure at various pH values was characterized by X-ray diffraction (XRD) as shown in Figure 1. Figure 1a indicates the XRD peaks of a tetragonal SnO marked with the ● symbols at (001), (101) and (002), which are well matched with the standard XRD data file (JCPDS-06-0395). The phase transformation from SnO to Sn 3O 4 occurred with decreasing pH, and the XRD patterns indicated the coexistence of SnO and Sn 3O 4 at pH 5 (Fig. 1b). Only Sn 3O 4 diffraction peaks existed at pH of less than 3, as shown in Figure 1d and e, where, the ■ symbols are assigned to (111), (-210), (-121), and (311) of a triclinic Sn 3O 4 (JCPDS-20-1293).[21] Notably, several unknown crystalline peaks were generated when the pH approached 1. Thus, controlling the pH value within 2 and 3 during the reaction is critical to synthesize well-defined Sn 3O 4 nanostructure.
Measurements with Raman spectroscopy also
confirmed the phase transformation from SnO to Sn 3O 4 at pH 5. The Raman peaks were collected with a 514 nm excitation laser. The Raman peaks of SnO at 113 and 211 cm -1 are seen in Figure 2a. The peaks from the SnO and Sn 3O 4 structures coexisted at pH 5. As the pH decreased, the Raman peaks of Sn 3O 4 at 143 and 170 cm -1 gradually appeared, as shown in Figure 2b. Only the Raman peaks of Sn 3O 4 existed at pH of less than 3 (Figs. 2d-e), which became more prominent with decreasing pH.[17] No other impurities were detected. The XRD and Raman spectra indicates the transition of the crystal structure from tetragonal SnO to triclinic Sn 3O 4 at pH 5 and the sole existence of Sn 3O 4 when adjusting the pH between 2 and 3.
The morphology of Sn 3O 4 was observed by using scanning electron microscopy (SEM) and transmittance electron microscopy (TEM). Figure 3 shows
the
variation
of
hierarchical
Sn 3O 4
morphology at different pH values. It was observed that the pH had a great influence on the
Figure 2. Raman spectra of the precipitates synthesized at different pH values; (a) SnO, (b) pH=5, (c) pH=4, (d) pH=3, and (e) pH=2. (●: SnO, ■: Sn 3O 4)
Figure 3. SEM images of the precipitates synthesized at different pH values; (a) SnO, (b) pH=5, (c) pH=4, (d) pH=3, (e) pH=2 and (f) a magnified SEM image of the hierarchical Sn 3O 4 nanospheres covered with nanoplates.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 突出的，显著的
杂质（impurity 的复数）
morphology of Sn 3O4. Indeed, if HCl was not added into the nutrient solution, then only SnO nanoparticles aggregated together as shown in Figure 3a.[28] At pH 5, the
neighboring nanoparticles aggregated into a prickly sphere with a diameter of approximately 100 nm (Fig. 3b). As the solution became more acidic (pH = 4, Fig. 3c), the prickly surface became prominent. At pH less than 3, in which the SnO was completely transformed into the hierarchical Sn3O4, the prickles were dissolved and recrystallized into nanoplates as shown in Figure 3d and 3e.[29] Figure 3f shows a magnified hierarchical Sn3O4nanosphere having irregularly oriented thin nanoplates with a radius of 20 nm.
Figure 4a and b are TEM images that clearly show the aggregated Sn3O4nanospheres covered with the protruded thin nanoplates. Figure 4c-e are the HR-TEM images of a nanoplate at different pH values. During the dissolution and recrystallization of the nanoplate, the lattice was aligned along the direction of the more stable thermodynamic plane.[29] At pH 5, the nanoplate had conspicuous grain boundaries with an averaged grain size of 5 nm and the lattice was misaligned at the grain boundaries (Fig. 4c). At pH 2, the grain boundaries disappeared and the lattice fringes became perfectly aligned along the [111] direction with a spacing of 0.329 nm. Eventually, single crystalline triclinic phase Sn3O4nanoplates were formed under strong acidic ambient condition. However, the mechanism of the lattice alignment and the nanoplate formation have not been clearly understood.
3.2. Characterization of the hierarchical Sn3O4 nanostructure
The porous nature of the hierarchical Sn3O4 nanostructure was investigated by nitrogen (N2) gas adsorption/desorption isotherms analysis via the Brunauer-Emmett-Teller (BET) method as shown in Figure 5. All the hierarchical Sn3O4nanostructures followed mesoporous type (IV) isotherm with a hysteresis loop. In the case of highly mesoporous materials, a hysteresis loop was remarkable by the phenomenon of capillary condensation.[30] The BET surface area of SnO was 8.92 m2g-1. The other hierarchical Sn3O4nanostructures synthesized at different pH values had BET surface areas of 11.68, 12.26, 46.48 and 55.05 m2g-1 with decreasing the pH from 5 to 2, respectively. The amount of adsorbed nitrogen increased dramatically after complete conversion of SnO into the hierarchical Sn3O4. The
Figure 4. (a) TEM and (b) HR-TEM image of the hierarchical
Sn3O4nanospheres covered with nanoplates. HR-TEM images of nanoplates synthesized at (c) pH=5, (d) pH=4 and (e) pH=2, showing the alignment of lattice fringes with decreasing pH. (Scale bar is 2 nm). Figure 5.N2adsorption-desorption isotherms of all products. Inset figure is the pore-size distribution of the hierarchical Sn3O4 nanostructure synthesized at pH=2.
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Sn 3O 4 structure synthesized at pH 2 had the highest value of BET surface area, indicating a highly porous structure caused by intensive etching in such a strong acidic ambient condition. The inset of figure 5 demonstrates the pore size distribution of hierarchical Sn 3O 4 at pH 2, revealing a maximum at 40 ?.
UV-Vis. absorption spectra of the Sn 3O 4 structures are shown in Figure 6. In the case of SnO, there was no absorption in the UV wavelengths and comparatively negligible absorption in the visible wavelengths. The respective absorption edges of the Sn 3O 4 structures are 397, 445, 480 and 550 nm with decreasing pH values from 5 to 2, respectively. By using the equation of E g = 1240/λ (λ = the wavelength of absorption edge), the corresponding band gap of the Sn 3O 4 structures are calculated to be 3.12, 2.78, 2.58 and 2.25 eV , respectively. These results indicate that the band gap of the hierarchical Sn 3O 4 nanostructure becomes lower with decreasing pH. In comparison, the commercially available P25 (TiO 2, Degusa) photocatalyst had an absorption edge of 350 nm, corresponding to a band gap of 3.54 eV , and a negligible absorbance at visible wavelengths.
The inset image of Figure 6 shows that the color of the Sn 3O 4 structures varies from black to yellow, which corresponds to the powder of SnO and the hierarchical Sn 3O 4 structures synthesized with decreasing pH values. Considering the UV-Vis. absorption spectra and the calculated bandgap, the hierarchical Sn 3O 4 nanostructure synthesized in strong acidic ambient condition can absorb both UV and visible light. Thus, this material can effectively use the sun light, from which most radiation comes in visible wave lengths with a spectrum peak at yellow wavelength.
3.3. Photocatalytic activity of the hierarchical Sn 3O 4 nanostructure
The photocatalytic activity of the mesoporous hierarchical Sn 3O 4 nanostructure synthesized at pH 2 was tested by measuring the photo-decomposition of MO under one-Sun condition (air mass 1.5). The P25 photocatalyst was also tested to compare its performance with the synthesized SnO and Sn 3O 4 structures. Because the P25 (TiO 2) has the merits of inexhaustible abundance with no photo-corrosion and non-toxicity,[31-33] many research groups have studied the photocatalytic phenomena of TiO 2 under irradiation with UV light.[34-37] However, because of its wide band gap, the TiO 2 cannot excite electrons at the valence band under irradiation with visible light as shown in Figure 6. For direct comparison, the same amount of each photocatalyst (0.05 g) was added into an excessively concentrated (30 vol. %) MO solution in 100 ml deionized water to determine the photocatalytic ability in such an extreme condition.
Usually, the MO has been used as a pH indicator and utilized in various industrial fields such as textile, printing, paper, food and so on. However, it has mutagenic side-effects and often pollutes the
environment. Thus, the elimination of MO in solution is necessary for the environment and healthy life. When the photocatalyst absorbs light
from the Sun or an artificial light source, it produces
Figure 6. UV-Vis. absorption spectra of the tin-related products; (a) SnO, (b) pH=5, (c) pH=4, (d) pH=3, (e) pH=2 and (f) P25. Inset image shows the color change of as-made powder synthesized at different pH values.
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pairs of electron and hole. The generated holes attack surrounding water molecules to generate hydroxyl radicals (*OH) at the surface of photocatalysts as depicted in the following photo-oxidation mechanism;[38]
Metal oxide + hv → e -CB + h +VB (1) h +VB +H 2O → *OH + H +
(2)
It is known that the hydroxyl radical has the second largest oxidation potential of 2.8 V among several common oxidants including fluorine (3.03 V), ozone (2.07 V), hydrogen peroxide (1.77 V) and chloride (1.36 V). Therefore, the *OH can rapidly attack and cleave the aromatic rings of organic pollutants.[39] Figure 7a represents the variation of MO concentration (C/C o ) as a function of exposure time under one-Sun condition. The decomposition efficiency of the photocatalyst is described as follows:
Photo-decomposition (%) = (1 - C/C o ) x 100 % (3)
where, C o is the initial concentration of MO solution before irradiation and C is its concentration after irradiation. After 1 hour exposure under one-Sun condition, no decomposition of MO was observed in the case of SnO because it had a small BET surface area and a negligible light absorbance over entire wavelengths. In the case of P25, the photo-decomposition proceeded slowly; 80 % of the MO remained after 15 min exposure and it took 1
hour to decompose all the MO contents because this photocatalyst was active only at UV wavelengths. Unlike the P25, the mesoporous hierarchical Sn 3O 4 nanostructure synthesized at pH 2 demonstrated a rapid photo-decomposition owing to its narrow band gap, enabling to absorb the intense visible and UV light concurrently. The MO was completely decomposed within 15 min with only 0.05 g of Sn 3O 4.
Figure 7b and c present the variation of the absorption spectra of MO solution with different exposure times when using the Sn 3O 4 and P25, respectively. In the case of Sn 3O 4 photocatalyst, the in tensity of the MO absorption peak (λ = 485 nm) was dramatically attenuated (Figure 7a). After 15 min exposure, the color of the MO solution became bleached as shown in the inset of Figure 7b, suggesting that the entire MO was completely decomposed within 15 min. In contrast, the MO absorption peak gradually decreased with exposure time when using the P25. The inset of Figure 7c confirms the gradual color change of the solution with exposure time.
The photo-decomposition rate of MO can be calculated by the following equation;[14]
-ln(C/C o ) = κt
(4)
Figure 7. (a) A comparison of the photocatalytic activity of three
different
photocatalysts
by
measuring
the
photo-decomposition of methyl orange (MO) solution under one-Sun condition. UV-Vis. absorption variation of the MO solution with irradiation time when using 0.05 g of (b) Sn 3O 4 and (c) P25 photocatalyst. The respective inset image shows the color change of MO solution as a function of irradiation time.
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Table 1. Photo-decomposition rate of MO solution
-1
(a) SnO 1.09 x 10-3
(b) P25 1.58 x 10-2
(c) Sn3O4 1.73 x 10-1
where κ (min-1) is the photo-decomposition rate constant. The κ value of each photocatalyst after 15 min irradiation is summarized in Table 1. The Sn3O4 exhibited much faster photo-decomposition activity compared with the other two photocatalysts. The k value of Sn3O4is 1.73 x 10-1min-1under one-Sun condition, which is a 90.86 % enhancement com-pared to the decomposition rate constant of P25 (1.58 x 10-2min-1). Considering the complete removal of the extremely concentrated MO solution (30 %), the photocatalytic ability of the hierarchical Sn3O4nanostructure is superb. The excellent performance can be ascribed to its large surface area, permitting widespread contact to the MO solution, and its narrow band gap, effectively utilizing the visible light of the Sun.
4. Conclusion
Hierarchical Sn3O4nanospheres covered with nanoplates were synthesized via a simple hydrothermal method in strong acidic ambient condition. X-ray diffraction and Ra-man spectroscopy evidenced that only triclinic Sn3O4 was produced from the SnO at a pH of 3 by dissolution and recrystallization. During recrystallization, the lattice of the nanoplate was aligned along the thermodynamically stable [111] plane. The hierarchical Sn3O4nanostructure (0.05 g) possessed an ability to fully decompose 30 % MO in 100 ml deionized solution in 15 min under one-Sun condition with a decomposition rate of 1.73 x 10-1 min-1. Notably, the decomposition rate is a 90.86 % enhancement compared with that of the commercially available P25. The high photo-decomposition activity of the hierarchical Sn3O4nanostructure was resulting from a BET surface area of 55.05 m2g-1and its narrow band gap of 2.25 eV, capable of absorbing the visible light.
Acknowledgements
This work was supported by the Basic Science Research program through the National Research Foundation of Korea funded by the Pioneer Research Center Program (NRF, No. 2014M3C1A3016468) and the GIST Specialized Research Project provided by GIST.
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SnO2介孔材料的制备研究进展 二氧化锡是一种n型半导体材料，带隙（Eg）为3.6ev，除具有良好的阻燃和导电性能外，还有反射红外线辐射和吸附以及稳定性高等特点，因此在工业上有着极为广泛的应用。可用于有机物氧化的催化剂和气体传感器[1，2]，蓄电电池[3]以及光电设备[4]中。而介孔二氧化锡相较于二氧化锡块体材料，具有更为优越的性能，如比表面积更大。孔材料的这种优势在很早以前就被发现，但是开发这种新材料面临着一个巨大的挑战，就是怎么样设计出精确的合成路线，以控制材料的组成、结构性质和高孔隙率。事实上，以模板剂或结构导向剂至孔的软化学制备路线正逐步的开拓新的孔材料。美国Mobil公司的Beck等[5]在温和的水热体系中合成出了具有均匀规整孔道结构和狭窄孔径分布的新型中孔分子筛材料FMS-16和M41S。这类中孔硅材料具有孔径分布狭窄的介孔(1.5~10.0nm)、大比孔容、高比表面积和强吸附能力，并可根据需要调整孔径和酸性密度、强度，预示着这类分子筛在渣油催化裂解、重油加氢、润滑油加氢、烷基化、烯烃聚合等酸性催化领域及石油化工的分离过程中具有广阔的应用前景。它的出现使孔材料的研究由微孔进入中孔阶段，成为孔材料发展过程中的一个重要里程碑。在此后不久，这种制备技术被应用于制备其它的介孔金属氧化物。这些介孔材料具有大的比表面积、狭窄的孔径分布使其在催化剂、分子筛、气体传感器以及固体离子电极等方面极具竞争力[4]。 本文综述了近年来介孔SnO2的制备路线，结构和表征方法。 一、介孔二氧化锡的制备 介孔二氧化锡的制备方法很多，包括模板法、溶胶－凝胶法、水热合成法以及阳极氧化法等。其中最为主要的方法是模板法。 1.模板法 模板法是利用模板剂（如表面活性剂）分子与无机物种在一定的条件下通过静电吸引、氢键等作用力界面组装形成有机物－无机物的复合物，从而实现对介孔材料的剪裁。它可以控制材料的结构性质包括外形，内部孔隙率和比表面积。模板剂种类繁多，可以是表面活性剂、无机晶体或生物材料等。不同的模板剂，与无机前体的作用力也各不相同，而呈现出不一样的合成路线。如下表所示： 表1几种典型的中孔材料合成路线a 合成路线S+I-S-I+S-X-I+S-M+I-S0I0 作用力静电引力氢键 示意图 + + X + M+N H H O O O a. S+表示阳离子表面活性剂，如长链烷基季铵盐、长链烷基吡啶盐或双阳离子(Gemini)型季铵盐等；S-表示阴离子表面活性剂，如各种盐型(如羧酸盐、硫酸盐等)和酯盐型(如磷酸酯、硫酸酯等)；S0表示非离子表面活性剂，如聚烷氧基醚、非离子Gemini型长链烷基
纳米氧化锡的用途及研究进展 付高辉0909404018 高分子材料与工程 1 前言 氧化锡是一种宽带系半导体材料，带宽范围为 3.6～4．0 eV。它用途广泛，在有机合成中，可用作催化剂。在陶瓷工业中，可作为釉料和搪瓷乳浊剂。由于小尺寸效应及表面效应，纳米氧化锡具有特殊的光电性能、气敏性能、催化性能以及具有化学和机械稳定性，在气敏元件、半导体元件、电极材料、液晶显示器、保护性涂层及太阳能电池等方面有着潜在的应用。是一种重要的半导体金属氧化物功能材料。 鉴于纳米材料的表面原子数与体相原子数之比随颗粒尺寸的减小而急剧增大，从而显示出体积效应、量子尺寸效应、表面效应和宏观量子隧道效应，在光、电、磁、力、化学等方面呈现出一系列独特的性质，人们自然致力研究SnO 纳米 2 材料的制备。[1-3 ] 2 纳米氧化锡的性质 2.1 化学稳定性 纳米氧化锡材料因其也为惰性金属氧化物，不易发生化学反应。因此在好多反应中都保持了自己的性质，这为开发多功能的新型材料提供了保证。 2.2 量子尺寸效应 当超细微粒的尺寸与光波波长、德布罗意波长以及超导态的相干长度或透射 周边性的边界条件将被破坏，导致声、深度等物理尺寸相当或更小时，纳米SnO 2 光、电、磁、热、力学等性质呈现出新的小尺寸效应。利用这些小尺寸效应，在使用技术方面开辟了一些新的领域。 2.3 宏观量子隧道效应 宏观量子隧道效应即当微观粒子的总能量小于势垒高度时，该粒子仍能穿越这一势垒。近年来，人们发现一些宏观量，例如微颗粒的磁化强度，量子相干器件中的磁通量等亦有隧道效应，称为宏观的量子隧道效应。而纳米SnO 的宏观量 2 子隧道效应为其在微电子器件发面的发展奠定了良好的基础。
有毒有机锡的危害与预防 有机锡化合物有4种类型：四烃基锡化合物（R4Sn）、三烃基锡化合物（R3SnX）、二烃基锡化合物（R2SnX2）和一烃基锡化合物（RSnX3）,以上通式中R为烃基，可为烷基或芳基等；X为无机或有机酸根、氧或卤族元素等。根据国内外病便报道，引起急性中毒性脑病的主要有机锡化合物有三甲基锡（trimethyltin）,三甲基氯化锡（trimethyltin chloride）、三乙基锡（triethyltin）、三乙基氯化锡（triethyltin chloride）、三乙基溴化锡（triethyltin bromide）、三乙基碘化锡（triethyltin iodide）、三乙基氢氧化锡（triethyltin hydroxide）、三乙基硫酸锡（triethyltin sulfate）、双三乙基硫酸锡（bis(triethyltin) sulfate)、三丁基氯化锡（tributyltin chloride）、三苯基氯化锡（triphenyltin chloride）、三苯基乙酸锡（triphenyltin acetate）、四乙基锡（tetraethyltin）、四丁基锡（tetrabutyltin）、四苯基锡（tetraphenyltin）和三乙基溴化锡苯胺络合物的1/10滑石粉制剂（乌米散）等。有机锡化合物多为固体或油状液体，具有腐败青草气味。常温下易挥发。不溶或难溶于水，易溶于有机溶剂。部分此类化合物可被漂白粉或高锰酸钾分解形成无机锡。有机锡化合物主要用作聚氯乙烯塑料稳定剂，也可用作农业杀菌剂、油漆等的防霉剂、水下防污剂、防鼠剂等。四烃基锡为制备其他有机锡化合物的中间体。在应用有机锡防污涂料的舰艇等附近的水域可受污染。在作业时可因防护不当，设备故障或违章操作而致作业者大量接触有机锡。有机锡一般可经呼吸道吸收，
二氧化锡半导体纳米粉体的制备及气敏性能研究报告 学院：资源加工与生物工程学院 班级：无机0801 姓名：魏军参 学号：0305080723 组员：张明陈铭鹰项成有
半导体纳米粉体的制备及气敏性能研究 前言 SnO2 粉体作为一种功能基本材料，在气敏、湿敏、光学技术等方面有着广泛的应用。目前是应用在气敏元件最多的基本原材料之一。纳米级SnO2 对H2 、C2H2 等气体有着较高的灵敏度、选择性和稳定性，具有更广阔的应用市场前景。研究纳米SnO2 粉体的制备方法很多，例如：真空蒸发凝聚法、低温等离子法、水解法、醇盐水解法、化学共沉淀法、溶胶—凝胶法，近期还出现了微乳液法，水热合成法等。每种制粉方法各有特点，但是在目前技术装备水平和纳米粉体应用市场还未真正形成的条件下，上述纳米粉体制备方法由于技术成熟度或制备成本等方面的原因，大多都还未形成具有实际意义上的生产规模，主要还处于提供研究样品阶段。 以廉价的无机盐SnCl4·5H2O为原料，采用溶胶-凝胶法制备出粒度均匀的超细SnO2粉体，该工艺具有设备简单，过程易控，成本低，收率高等优点。实验考察制备工艺过程中原料浓度、反应温度、反应终点pH值、干燥脱水方式、培烧温度等因素对纳米SnO2粉体粒径的影响。实验过程以TG-DTA热分析、红外光谱等测试手段，分析前驱体氢氧化物受热行为，前驱体表面基团及过程防团聚机理等。利用透射电子显微镜、X-射线衍射仪、比表面测试仪分别对纳米粒子的形貌与粒径分布、晶相组成、比表面积进行了表征与测定。 在实验中制备得到得SnO2 胶体，在干燥、煅烧的过程中很容易形成团聚。因为粉体颗粒细小, 表面能巨大, 往往会粘结在一起。水热法是近年来出现的制备超细粉体的新方法，其利用密封压力容器, 以水为溶剂, 温度从低温到高温(100 ℃～400 ℃) , 压力在10～200 MPa 。该方法为前驱物反应提供了一个在常压下无法实现的特使物理化学条件。避免在普通煅烧过程中, 由于晶粒间细小间隙产生毛细现象导致的颗粒长大团聚。 水热法制备过程中, 粉体在液相中达到“煅烧”温度。通过控制反应条件, 有效阻碍颗粒间的长大, 保持颗粒粒度均匀, 形态规则, 且干燥后无需煅烧, 避免形成硬团聚。 本文以SnCl4·5H2O 为原料, 利用溶胶凝胶法和离心洗涤制备纯净凝胶, 水热脱水法制备SnO2微晶；研究不同水热条件下, SnO2 粉体的形成、晶粒大小以及分散性能。 文献综述 1.1 半导体纳米粉体 半导体定义 电阻率介于金属和绝缘体[1]之间并有负的电阻温度系数的物质。半导体室温时电阻率约在10E-5～10E7欧姆?米之间，温度升高时电阻率指数则减小。半导体材料很多，按化学成分可分为元素半导体和化合物半导体两大类。锗和硅是最常用的元素半导体；化合物半导体包括Ⅲ-Ⅴ族化合物（砷化镓、磷化镓等）、Ⅱ-Ⅵ族化合物( 硫化镉、硫化锌等)、氧化物(锰、铬、铁、铜的氧化物),以及由Ⅲ-Ⅴ族化合物和Ⅱ-Ⅵ族化合物组成的固溶体（镓铝砷、镓砷磷等）。除上述晶态半导体外，还有非晶态的玻璃半导体、有机半导体等。 本征半导体：不含杂质且无晶格缺陷的半导体称为本征半导体。在极低温度下，半导体的价带是满带(见能带理论)，受到热激发后，价带中的部分电子会越过禁带进入能量较高的空带，空带中存在电子后成为导带，价带中缺少一个电子后形成一个带正电的空位，称为空穴。导带中的电子和价带中的空穴合称电子 - 空穴对，均能自由移动，即载流子，它们在外电场作用下产生定向运动而形成宏观电流，分别称为电子导电和空穴导电。这种由
有毒有机锡的危害与预防有机锡化合物有4种类型：四烃基锡化合物（R4Sn）、三烃基锡化合物（R3SnX）、二烃基锡化合物（R2SnX2）和一烃基锡化合物（RSnX3）,以上通式中R为烃基，可为烷基或芳基等；X为无机或有机酸根、氧或卤族元素等。根据国内外病便报道，引起急性中毒性脑病的主要 有机锡化合物有三甲基锡（trimethyltin）,三甲基氯化锡（trimethyltinchloride）、三乙基锡（triethyltin）、三乙基氯 化锡（triethyltinchloride）、三乙基溴化锡（triethyltinbromide）、三乙基碘化锡（triethyltiniodide）、三乙基氢氧化锡（triethyltinhydroxide）、三乙基硫酸锡（triethyltinsulfate）、双三乙基硫酸锡（bis(triethyltin)sulfate)、三丁基氯化锡（tributyltinchloride）、三苯基氯化锡（triphenyltinchloride）、三苯基乙酸锡（triphenyltinacetate）、四乙基锡（tetraethyltin）、四丁基锡（tetrabutyltin）、四苯基锡（tetraphenyltin）和三乙 基溴化锡苯胺络合物的1/10滑石粉制剂（乌米散）等。有机锡化合 物多为固体或油状液体，具有腐败青草气味。常温下易挥发。不溶 或难溶于水，易溶于有机溶剂。部分此类化合物可被漂白粉或高锰 酸钾分解形成无机锡。有机锡化合物主要用作聚氯乙烯塑料稳定剂，也可用作农业杀菌剂、油漆等的防霉剂、水下防污剂、防鼠剂等。 四烃基锡为制备其他有机锡化合物的中间体。在应用有机锡防污涂 料的舰艇等附近的水域可受污染。在作业时可因防护不当，设备故
二氧化锡 二氧化锡别名氧化锡，化学式SnO?。主要用途：本产品用作电子元器件生产、搪瓷色料、锡盐制造、大理石及玻璃的磨光剂;制造不透明玻璃、防冻玻璃和高强度玻璃等，还可用于对有害气体的监测。 1基本内容 二氧化锡tin oxide ; stannic oxide:stannic anhydride； 别名氧化锡 化学式SnO? 分子式(Formula)： SnO2 分子量(Molecular Weight)： 150.69
CAS No.： 18282-10-5 2性质 二氧化锡结构白色四角晶体, 密度7,熔点1127摄氏度.不溶于水,稀酸和碱液.溶于浓硫酸.与碱共溶形成锡酸盐.用于制造不透明玻璃,瓷铀和玻璃擦光剂.天然产的是锡石.可由锡在空气中灼烧而制得. 又名氧化锡，式量150.7。白色，四方、六方或正交晶体，密度为6.95克/厘米3，熔点1630℃，于1800～1900℃升华。难溶于水、醇、稀酸和碱液。缓溶于热浓强碱溶液并分解，与强碱共熔可生成锡酸盐。能溶于浓硫酸或浓盐酸。用于制锡盐、催化剂、媒染剂，配制涂料，玻璃、搪瓷工业用作抛光剂。锡在空气中灼烧或将Sn(OH)4加热分解可制得。 3用途 1.用于制造不透明玻璃,瓷铀和玻璃擦光剂； 2.用于制锡盐、催化剂、媒染剂，配制涂料，玻璃、搪瓷工业用作抛光剂。 3.用作搪瓷色料、锡盐制造、大理石及玻璃的磨光剂; 4.制造不透明玻璃、防冻玻璃和高强度玻璃等。 5.新型环保银氧化锡电触头材料的原料。（替代有毒的银氧化镉材料） 6.制备熔炼玻璃的二氧化锡电极。 7.制动块 8.催化作用和气体探测的的高级表面活性材料。（SnO?为敏感材料制成的 “气——电”转换器。） 4安全性
二氧化锡纳米传感器发展趋势及应用 文章概述了基于二氧化锡纳米传感器的发展趋势及应用，主要综述各种形貌的纳米二氧化锡材料的制备方法，以及其在气体传感器（CO，CO2，H2，SO2，NOx等）方向的应用。 标签：二氧化锡；纳米材料；气体传感器 纳米材料是指三维空间中至少有一维处于纳米尺寸范围（1-100 nm）或由它们作为基本单元构成的材料，具有表面效应、量子尺寸效应、小尺寸效应、宏观量子隧道效应等特性[1]。近年来，随着科学技术的飞速发展，纳米材料的合成及其基础应用一直受到广泛的关注。金属氧化物（MxOy）纳米材料（纳米线，纳米管，纳米带等）因其特有纳米结构及其在基础研究领域和工业中的潜在应用引起了人们特别的关注。在这些金属氧化物中，二氧化锡（SnO2）是一种重要的宽带隙（3.6-4.0 eV）金属氧化物半导体材料，因其优良的物理化学性能，被应用在诸多领域，如气敏传感器、透明导电薄膜、太阳能电池、催化剂等[2]。 传感器是指能感受规定的被测量并按照一定的规律转换成可用输出信号的器件或装置，通常由敏感元件和转换元件组成。气体传感器（Gas Sensor）是以气敏器件为核心组成的将被测气体浓度转换为与其成一定关系的电量输出的装置或器件。它具有响应快，定量分析方便，成本低廉，实用性广等优点。从半导体气敏元件的产生至今，半导体气体传感器已有近五十年的发展。由于其小尺寸效应及表面效应，纳米SnO2具有特殊的气敏性能，在气体传感器方面有着潜在的应用。1962年Fafuchi等制作了世界上首只SnO2气体传感器，并于1968年实现了商品化，这极大的推动了半导体气敏元件的发展[3-5]。 本文主要對近年来SnO2纳米传感器中纳米SnO2的各种制备方法进行总结，同时突出其近年来在气体传感（一氧化碳，二氧化碳，氮氧化物，二氧化硫等）方向的研究现状以及未来的发展趋势。 1 纳米SnO2的不同制备方法 1.1 溶液法 溶液法是制备纳米金属氧化物最常用的，最有效的方法，具有反应条件温和，操作简单、产率高以及形貌可控等优点。溶液法主要包括水热法和化学沉积法。Firooz等人通过水热法制备得到SnO2纳米颗粒和纳米棒[6]。首先，将SnCl2·2H2O和氢氧化钠溶液混合搅拌至溶液澄清，随后加入溴化十六烷三甲基铵（CTAB）加入溶液中，130℃反应24h，制备得到SnO2纳米颗粒和纳米棒。吴等人通过水热法改变不同的反应条件制备得到多种不同形貌的SnO2纳米结构[7]。化学沉积法与水热法反应过程相似，但化学沉积法一般在低于100℃的敞开体系中。徐等人在95℃下，将SnCl2·5H2O与水的沉淀物与尿素溶液一起搅拌，随后将铝管插入反应体系中，反应六小时后，SnO2纳米片沉积在铝管上[8]。
SnO2体材料的密度为5.67g/cm，通常制备的SnO2薄膜密度大约为体材料密度的80～90%，熔点为1927摄氏度。SnO2及其掺杂薄膜具有高可见光透过率、高电导率、高稳定性、高硬度和极强的耐腐蚀性等性能。宽带隙半导体的纳米线具有巨大的纵横比，表现出奇特的电学和光学性能，使其在低压和短波长光电子器件方面具有潜在的应用前景。与传统SnO2相比,由于SnO2 纳米材料具有量子尺寸效应、小尺寸效应、表面效应和宏观量子隧道效应,因而在光、热、电、声、磁等物理特性以及其他宏观性质方面都会发生显著的变化。 二、纳米氧化锡的制备 1.固相法 1)高能机械球磨法 高能机械球磨法是利用球磨机的转动或振动,对原料进行强 烈的撞击、研磨和搅拌。 2)草酸锡盐热分解法 2.液相法 1)醇—水溶液法 2)溶胶—凝胶法 溶胶—凝胶法的基本原理是:金属醇盐或无机盐在有机介质 中经水解、缩聚,形成溶胶,溶胶聚合凝胶化得到凝胶,凝胶经 过加热或冷冻干燥及焙烧处理,除去其中的有机成分,即可得 到纳米尺度的无机材料超细颗粒。
3)微乳液法 微乳液法是将两种反应物分别溶于组成完全相同的两份微乳液中;然后这两种反应物在一定条件下通过物质交换彼此发生反应,借助超速离心,使纳米微粒与微乳液分离;再用有机溶剂清洗除去附着在表面的油和表面活性剂;最后在一定温度下干燥处理,即可得到纳米微粒的固体样品。 4)沉淀法 沉淀法分直接沉淀法和均匀沉淀法，直接沉淀法是制备超细氧化物广泛采用的一种方法,它是在含有金属离子的溶液中加入沉淀剂后,于一定条件下生成沉淀,除去阴离子,沉淀经热分解。均匀沉淀法是利用某一反应使溶液中的构晶离子从溶液中缓慢均匀地释放出来。制得超细氧化物。 5)水热法 水热法制备超细微粉的技术始于1982年,它是指在高温、高压下一些氢氧化物在水中的溶解度大于对应氧化物在水中的溶解度,氢氧化物溶入水中同时析出氧化物。 6)微波法 7)锡粒氧化法 3.气相法 1)等离子体法 等离子体法是在惰性气氛或反应性气氛下通过直流放电 使气体电离产生高温等离子体,使原料熔化和蒸发,蒸气遇
锡焊的危害性 锡焊在焊接时由于高温会产生二氧化锡，长期吸入二氧化锡会导致肺部病变 但是焊接时戴上防毒面罩是可以避免的 相反在焊接电子面板时，高温会使面板上的苯类膜（绿色或红色等）烧掉，烧掉的同时会挥发出剧毒的苯化合物 这些都是对人体产生毒害的...特别是女人 对孕期女人尤为影响 会对胎儿的成长相当不利！！！ 希望呢对你有点儿帮助...(*^__^*) 异丙醇的危害 助焊剂异丙醇的危害性说明如下:接触高浓度蒸汽出现头痛、倦睡、共济失调以及眼、鼻、喉刺激症状。口服可致恶心、呕吐、腹痛、腹泻、倦睡、昏迷甚至死亡。长期皮肤接触可致皮肤干燥、皲裂。车间卫生标准为400ppm左右,一般二氧化碳差不多350ppm左右,所以如果化学使用区域有局部排风系统,或者车间通风良好的话,一般不会对人体产生危害. 关于锡膏,加热时会有二氧化锡烟气产生,同时溶在锡膏中的松
香等也会释放出来,锡炉是需要加装局部排风的.我们厂的话每年还要做检测,检测锡炉旁边铅烟和二氧化锡的浓度,一般都不超过国家规定的标准的. 助焊剂有好多,里面的成分也各不相同,一般会有松香及醇类物质,宜避免吸入和食入. 如果什么防护措施都没有的话,说明工厂的环安工作做的很差劲,至少应该做到在一个良好的通风环境下作业.另外工作也应提供防护用品,如化学防护手套和活性炭口罩. 作为操作工,也要学会保护自己,养成个人良好的卫生习惯,一定要做到操作时不能进食和喝水/饭前需洗手等. 电焊危害 1、大量研究表明，电焊作业存在与职业接触有关的神经系统损害，主要涉及记忆、分析、定位等信息加工处理的功能，表现为神经生理、神经心理、神经行为异常[9]，与电焊烟尘中的锰、铝、铅等有密不可分的联系。采用WHO．NCTB测试,结果行为功能总分与尿锰存在负相关[10],提示神经行为功能的变化可作为预防锰中毒的早期指标之一[11]。国外研究有电焊作业
氧化锡基纳米材料的制备及应用 应化081（10082072）X明辉 摘要：纳米氧化锡因其独特的性质，在诸多领域中都具有广阔的应用前景，如导电填料，气敏传感器、催化剂、变阻器、陶瓷、透明导电氧化物薄膜和隔热涂料等，是一种极具发展潜力的新型导电材料。本文按照固相法、液相法、气相法综述了目前常见的纳米二氧化锡合成方法，比较了各种方法的优缺点，并简要介绍了其表征。 关键词：纳米材料，氧化锡，制备方法 1 研究背景 纳米材料是指在三维空间中至少有一维处于纳米尺寸X围（1-100nm），或者以它们作为基本单元构成的材料。按纳米材料的几何特征，人们常将其分为零维纳米材料（如纳米团簇、纳米微粒、人造原子）、一维纳米材料（如纳米碳管、纳米纤维、纳米同轴电缆）、二维纳米材料（纳米薄膜）和纳米晶体等。纳米材料尺寸小，比表面积大，具有量子尺寸效应，表面效应和宏观量子隧道效应，因此在光、热、电、声、磁等物理性质以及其他宏观性质方面都发生了显著地变化。所以人们试图通过纳米材料的运用来改善材料的性能。 SnO 2是一种重要的宽禁带n型半导体材料，带宽X围为3.6eV-4.0eV。SnO 2 是重要的 电子材料、陶瓷材料和化工材料。在电工、电子材料工业中，SnO 2 及其掺杂物可用于导电 材料、荧光灯、电极材料、敏感材料、热反射镜、光电子器件和薄膜电阻器等领域。在陶 瓷工业，SnO 2 用作釉料及陶瓷的乳浊剂，由于其难溶于玻璃及釉料中，还可用做颜料的载 体；在化学工业中，主要是作为催化剂和化工原料。SnO 2 是目前最常见的气敏半导体材 料，它对许多可燃性气体都有相当高的灵敏度。利用SnO 2 制成的透明导电材料可应用在 液晶显示、光探测器、太阳能电池、保护涂层等技术领域[1-3]。正是由于SnO 2 纳米材料的 广泛的应用背景，所以，纳米SnO 2 的制备技术已成为人们研究的热点之一。 2 文献综述 2.1 固相法合成SnO 2 纳米材料
二氧化锡化学品安全技术说 明书 第一部分：化学品名称化学品中文名称：二氧化锡 化学品英文名称：stannic oxide 中文名称2：氧化高锡 英文名称2：tin peroxide 技术说明书编码：1325CAS No.： 18282-10-5 分子式： SnO 2分子量：150.69第二部分：成分/组成信息 有害物成分含量CAS No.第三部分：危险性概述健康危害：吸入冶炼过程中产生的氧化锡烟尘可发生金属烟热，先感全身无力、头痛、咽干、口内金属味和胸部压迫感，有时伴有恶心、呕吐、咳嗽、气促等，继而寒战和发热。 长期吸入二氧化锡烟尘可引起锡肺（锡末沉着症）。可引起皮炎。燃爆危险：本品不燃。第四部分：急救措施皮肤接触：脱去污染的衣着，用流动清水冲洗。眼睛接触：提起眼睑，用流动清水或生理盐水冲洗。就医。吸入：迅速脱离现场至空气新鲜处。如呼吸困难，给输氧。就医。食入：饮足量温水，催吐。就医。第五部分：消防措施危险特性：未有特殊的燃烧爆炸特性。有害燃烧产物：氧化锡。灭火方法：本品不燃。尽可能将容器从火场移至空旷处。第六部分：泄漏应急处理应急处理：隔离泄漏污染区，限制出入。建议应急处理人员戴防尘面具（全面罩），穿防毒服。避免扬尘，小心扫起，置于袋中转移至安全场所。若大量泄漏，用塑料布、帆布覆盖。收集回收或运至废物处理场所处置。第七部分：操作处置与储存 有害物成分 含量 CAS No.: 二氧化锡 ≥98.5％ 18282-10-5
操作注意事项：密闭操作，局部排风。操作人员必须经过专门培训，严格遵守操作规程。建议操作人员佩戴自吸过滤式防尘口罩，戴化学安全防护眼镜，穿防毒物渗透工作服，戴乳胶手套。避免产生粉尘。避免与酸类、碱类接触。搬运时轻装轻卸，防止包装破损。配备泄漏应急处理设备。倒空的容器可能残留有害物。储存注意事项：储存于阴凉、通风的库房。远离火种、热源。应与酸类、碱类分开存放，切忌混储。储区应备有合适的材料收容泄漏第八部分：接触控制/个体防护中国M AC (mg /m 3)：未制定标准前苏联M AC (mg /m 3)：未制定标准TLVT N：2mg /m 3(按Sn 计)TLVW N：未制定标准监测方法：邻苯二甲酸紫比色法；栎精比色法工程控制：密闭操作，局部排风。呼吸系统防护：空气中粉尘浓度超标时，建议佩戴自吸过滤式防尘口罩。紧急事态抢救或撤离时，应该佩戴空气呼吸器。眼睛防护：戴化学安全防护眼镜。身体防护：穿防毒物渗透工作服。手防护：戴乳胶手套。其他防护：注意个人清洁卫生。 第九部分：理化特性主要成分：含量: ≥98.5％；铁≤0.04％；铜≤0.02％；铅≤0.05％；砷≤0.01％；硫≤0.01％；盐酸可溶物≤ 0.5％ 。外观与性状：白色无定形粉末。熔点(℃)：1127沸点(℃)：1800-1900(升华)相对密度(水=1)：6.6-6.9相对蒸气密度(空气=1)：无资料饱和蒸气压(kP a )：无资料燃烧热(kJ /m o l)：无意义临界温度(℃)：无意义临界压力(MP a )：无意义辛醇/水分配系数的对数值：无资料闪点(℃)：无意义引燃温度(℃)：无意义爆炸上限%(V /V)：无意义爆炸下限%(V /V)：无意义溶解性：不溶于水，溶于浓硫酸、盐酸。主要用途：用于锡盐、接触剂、化妆品制造、瓷釉、涂料、媒染剂、织物增重剂、磨光剂、乳白玻璃、不透明玻璃、搪瓷等的制第十部分：稳定性和反应活性禁配物：强酸、强碱。第十一部分：毒理学资料LD 50：无资料
学号：0809407009 姓名：张键专业：无机非 二氧化锡的制备,特性及应用 化学式:SnO2 氧化锡是白色四角晶体,密度7,熔点1127摄氏度.不溶于水稀酸和碱.溶于浓硫酸.与碱共溶形成锡酸盐.用于制造不透明玻璃,瓷铀和玻璃擦光剂.天然产的是锡石.可由锡在空气中灼烧而制得. 又名氧化锡，分子量150.7。白色，四方、六方或正交晶体，密度为6.95克/立方厘米，熔点1630℃，在1800～1900℃会升华。难溶于水、醇、稀酸和碱。能慢慢溶于热浓强碱溶液并分解，与强碱共熔可生成锡酸盐。能溶于浓硫酸或浓盐酸。用于制锡盐、催化剂、媒染剂，配制涂料，玻璃、搪瓷工业用作抛光剂。锡在空气中灼烧或将氢氧化锡加热分解可制得。 分子式(Formula)：SnO2 分子量(Molecular Weight)：150.69 CAS No.：18282-10-5 以上是二氧化锡的主要参数。我国生产二氧化锡的历史较长,但均采用传统的硝酸法进行生产。就是将锡溶于硝酸,生成偏锡酸,经多次水洗、干燥、煅烧、粉碎,得到黄色的二氧化锡,这种方法消耗的硝酸量比较大,而且环境污染严重,锡消耗高,产品纯度低,色泽达不到高档用品的要求。所起,尽管我国是锡出口国,却要用高价进口二氧化锡。 目前制备纳米氧化锡的方法主要有液相法和气相法两大类。常用的方法有溶胶—凝胶法，水热法，电弧气化合成法，交替化学法，低温等离子化学法，共沉淀法，微乳液法等等。现介绍几种方法。 1、溶胶——凝胶法。溶胶——凝胶法因其产品的均一性，高纯度和低合成温度而得到了成功的应用，该方法在制备制备纳米氧化锡方面应用也较多。如有人对溶胶——凝胶法制备纳米氧化锡的工艺参数，反应浓度，干燥的时间，温度等因素进行了研究，成功的制备了纳米氧化锡。又如以廉价的无机盐为原料，采用溶胶——凝胶法制备了颗粒小，孔径大，比表面高的氧化锡超细粉。溶胶——凝胶法所制的粉体具有颗粒尺寸均一，比表面高的，活性高，烧制温度低等优点，但在制备过程中由于受表面张力的影响，纳米粒子极易团聚在一起。为克服其缺点，最近在溶胶——凝胶法的凝胶干燥过程中有发展出真空干燥，冷冻干燥和超临界流体干燥等方法，其中超临界流体干燥法最引人注目，它能除去干燥过程中产生的表面张力和毛细，管作用。 2、水热法。水热法是在特制的密闭反应容器里，采用水溶液为反应介质，在高温，高压的条件下进行有关化学反应的总称。通过对容器加热，为各种前驱物的反应和结晶提供了一个在常压条件下无法得到的特殊物理，化学环境。水热法制备的纳米粒子具有晶粒发育完整，粒度小，分布均匀，颗粒团聚较少，分散性好和成分纯净等特点，而且制备过程污染小，成本低，工艺简单，尤其是无需后期的高温处理，避免了高温处理过程中晶粒的长大，缺陷的形成和杂质的引入，制得的粉体具有较高的烧结活性。 3、电弧气化合成法。电弧气化合成法的生产设备主要有电源设备，井式反应炉和收尘设备。生产过程：将精锡加热到500度呈液态，在井式反应炉中用电弧加热至2000度以上，激烈的电弧气化反应，产生大量的氧化锡蒸汽，经冷却结晶为超细颗粒，用吸尘设备收集，得到含微量锡及少量一氧化锡的混合超微粉末，再在空气中高温灼烧，使之氧化为氧化锡，得到高纯的超微氧化锡粉末。
化学沉淀法制备氧化锡纳米粉体Chemical precipitation method preparation of tin oxide nano powder 内容摘要 采用溶液化学沉淀法，在不同温度，不同反应时间，不同浓度及添加剂条件下考察了氧化锡纳米材料的制备。分别用 SEM、XRD、TEM等手段对产物进行表征，结合其组成、结构、性能等分析评价，进行了全面深入的研究。通过优化制备条件,得到了纯的纳米氧化锡。 关键字：纳米粉体氧化锡溶液化学沉淀法制备 Abstract Using chemical precipitation method, SnO2 nano materials were prepared under the condition of different temperature, different reaction time, different concentration and different additives by simple equipment. The products were characterized by means of SEM, XRD, TEM respectively. All the results were analysed and evaluated through combining its related composition, structure, performance, which help us to conduct a comprehensive in-depth study. By optimizing the preparation technology, we are able to get the ideal composition and morphology of tin oxide. Key words: nanopowder tin oxide chemical precipitation preparation 化学沉淀法制备氧化锡纳米粉体 纳米材料因具有量子尺寸效应, 小尺寸效应和表面效应等特性, 在光、电、热、磁等方面具有很多的特殊性能并得到了广泛研发[1]。纳米氧化锡作为一种新型纳米功能材料[2,3]，其空间结构特性、气敏性、光敏性、机械性能等在光电等许多领域都有极好的优越性，自1962 年以来,氧化锡在家庭、商业和工业领域都得到了广泛的应用[4], 诸如气敏探测器[5~8],电极材料[9]以及太阳能电池[10,11]等等。因此引起了广大研究者对氧化锡研究的广泛兴趣，在该材料的制备领域已取得了一定的成就。 但是利用简单设备，高产率的制备纳米氧化材料仍然存在挑战。制备 SnO 2