RESEARCH PAPER
Microwave-assisted rapid synthesis of Ag nanoparticles/graphene nanosheet composites and their application for hydrogen peroxide detection
Sen Liu ?Jingqi Tian ?Lei Wang ?Xuping Sun
Received:15December 2010/Accepted:4May 2011/Published online:15May 2011óSpringer Science+Business Media B.V.2011
Abstract Ag nanoparticles/graphene nanosheet (AgNPs/GN)composites have been rapidly prepared by a one-pot microwave-assisted reduction method,carried out by microwave irradiation of a N ,N -dimeth-ylformamide (DMF)solution of graphene oxide (GO)and AgNO 3.Several analytical techniques including UV–vis spectroscopy,FT-IR spectroscopy,Raman spectroscopy,X-ray diffraction (XRD),X-ray photo-electron spectroscopy (XPS),and transmission elec-tron microscopy (TEM)have been used to characterize the resulting AgNPs/GN composites.It suggests that such composites exhibit good catalytic activity toward reduction of hydrogen peroxide (H 2O 2),leading to a H 2O 2sensor with a fast amperometric response time of less than 2s.The linear detection range is estimated to be from 0.1to 100mM (r =0.999),and the detection limit is estimated to be 0.5l M at a signal-to-noise ratio of 3.
Keywords Graphene nanosheet áMicrowave áAg nanoparticle áHydrogen peroxide detection áSensors
Introduction
Graphene,a ?at monolayer of sp 2-bonded carbon atoms tightly packed into a two-dimensional (2D)honeycomb lattice,and characterized as ‘‘the thinnest material in our universe’’,has recently received considerable attention and due to its high surface area (*2600m 2/g),high chemical stability,and unique electronic,mechanical properties,which ensure its potential applications in nanoelectronics,nanocom-posites,Li ion batteries,sensors,etc.(Abdelsayed et al.2010;Allen et al.2010;Chen et al.2010a ,b ;Geim and Novoselov 2007;Novoselov et al.2004;Rao et al.2009;Stankovich et al.2006;Zhang et al.2005).In particular,metal nanoparticles/graphene nanosheet (GN)composites have attracted consider-able interest because of the combination remarkable unusual properties of metal nanoparticles with graph-ene and hence their synthesis has become a hot topic of scienti?c and technological importance (Kamat 2010;Liu et al.2010,2011;Muszynski et al.2008;Sundaram et al.2008;Vinodgopal et al.2010).Among them,Ag nanoparticles/GN (AgNPs/GN)composites have been proved to be a most promising material because AgNPs-containing materials are good candidates for optics,electronics,catalysis,and
Electronic supplementary material The online version of this article (doi:10.1007/s11051-011-0410-3)contains
supplementary material,which is available to authorized users.S.Liu áJ.Tian áL.Wang áX.Sun (&)
State Key Lab of Electroanalytical Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,Jilin,China e-mail:sunxp@https://www.doczj.com/doc/a29042470.html,
J.Tian
Graduate School of the Chinese Academy of Sciences,Beijing 100039,China
J Nanopart Res (2011)13:4539–4548DOI 10.1007/s11051-011-0410-3
electrochemistry(Hranisavljevic et al.2002;Sun et al. 2004;Zhang et al.2008).As a result,considerable attention has been paid on the synthesis of AgNPs/GN and AgNPs/graphene oxide(GO)composites(Hassan et al.2009;Li and Liu2010;Lightcap et al.2010;Lu et al.2009;Pasricha et al.2009;Shen et al.2010;Xu and Wang2009;Zhou et al.2009).For example, Pasricha et al.and Li et al.have prepared AgNPs/GN composites though a multiple-step method where AgNPs/GO composites were synthesized?rst,fol-lowed by the reduction of the composites by an extra reducing agent(Li and Liu2010;Pasricha et al.2009). Zhou et al.and Lightcap et al.have prepared AgNPs/ GN composites by in situ reduction of Ag precursor on GN pre-synthesized from GO(Lightcap et al.2010; Zhou et al.2009).However,all these methods are time-consuming and require complex manipulation process.Recently,a one-pot route has been developed to prepare AgNPs/GN composites where NaHB4or ethylene glycol was used as a reducing agent to reduce GO and AgNO3simultaneously(Hassan et al.2009; Shen et al.2010).On the other hand,microwave irradiation techniques(MIT)has been demonstrated as a rapid and high effective strategy for preparation of graphene-based materials.For example,MIT has been used for exfoliation of graphite(Li et al.2010;Wei et al.2008),reduction of GO(Chen et al.2010a,b; Janowska et al.2010;Zhu et al.2010a,b),and preparation of graphene-based hybrid materials(Guo et al.2010;Jasuja et al.2010;Murugan et al.2009; Zhang et al.2010).Hassan et al.have prepared AgNPs/ GN composites by one-step microwave-assisted heat-ing process in the presence of an extra reducing agent such as hydrazine hydrate,ethylenediamine,or ammo-nium hydroxide(Hassan et al.2009).However,the use of extra reducing agents may introduce heterogeneous impurities,and at the same time,complicate the synthetic procedure,limiting their further practical applications.
Herein,we report on one-pot,microwave-assisted preparation of AgNPs/GN composites by microwave irradiation of a N,N-dimethylformamide(DMF)solu-tion of GO and AgNO3for the?rst time,with the use of DMF acting as solvent and reducing agent.We further demonstrate that the resulting composites exhibit good catalytic activity toward the reduction of hydrogen peroxide(H2O2),leading to a H2O2sensor with a fast amperometric response time of less than 2s.The linear detection range is estimated to be from 0.1to100mM(r=0.999),and the detection limit is estimated to be0.5l M at a signal-to-noise ratio of3. Experimental
Chemicals and materials
Graphite powder,AgNO3,H2O2(30wt%)were purchased from Aladin Ltd.NaH2PO4,Na2HPO4, NaNO3,H2SO4(98wt%),KMnO4,and DMF were purchased from Beijing Chemical Corp.All chemi-cals were used as received without further puri?ca-tion.The water used throughout all experiments was puri?ed through a Millipore system.Phosphate buffer saline(PBS)was prepared by mixing stock solutions of NaH2PO4and Na2HPO4and a fresh solution of H2O2was prepared daily.
Apparatus
Raman spectra were obtained on J-Y T64000Raman spectrometer with514.5nm wavelength incident laser light.Powder X-ray diffraction(XRD)data were recorded on a Rigaku D/MAX2550diffractometer with Cu K a radiation(k=1.5418A?).Diffraction patterns were collected under ambient conditions in the2h range of4°–70°at a scanning rate of12°min-1. Transmission infrared spectra were collected in the transmission mode on a Nicolet560Fourier transform infrared(FTIR)spectrometer.X-ray photoelectron spectroscopy(XPS)analysis was measured on an ESCALABMK II X-ray photoelectron spectrometer. Transmission electron microscopy(TEM)measure-ments were made on a HITACHI H-8100electron microscopy(Hitachi,Tokyo,Japan)with an acceler-ating applied potential of200kV.The sample for TEM characterization was prepared by placing a drop of colloidal solution on carbon-coated copper grid and dried at room temperature.Electrochemical measure-ments were performed with a CHI660D electrochem-ical analyzer(CH Instruments,Inc.,Shanghai).A conventional three-electrode cell was used,including
a glassy carbon electrode(GCE,geometric area=
0.07cm2)as the working electrode,a Ag/AgCl(3M KCl)electrode as the reference electrode,and platinum foil as the counter electrode.All potentials given in this work are referred to the Ag/AgCl electrode.All the experiments were carried out at ambient temperature.
Synthesis of GO
GO was prepared from natural graphite powder using modi?ed Hummers method(Hummers and Offeman 1958)as follows:In a typical synthesis,1g of graphite was added into23mL of98%H2SO4, followed by stirring at room temperature over a24h period.After that,100mg of NaNO3was introduced into the mixture and stirred for30min.Subsequently, the mixture was kept below5°C by ice bath,and3g of KMnO4was slowly added into the mixture.After being heated to35–40°C,the mixture was stirred for another30min.After that,46mL of water was added into above mixture during a period of25min. Finally,140mL of water and10mL of30%H2O2 were added into the mixture to stop the reaction. After the unexploited graphite in the resulting mixture was removed by centrifugation,as-synthe-sized GO was dispersed into individual sheets in distilled water at a concentration of0.5mg/mL with the aid of ultrasound for further use.
Synthesis of AgNPs/GN
AgNPs/GN was prepared by microwave-assisted reduction of GO and AgNO3with the use of DMF as a reducing agent and solvent.In a typical synthesis, 1.0mL of GO aqueous was added into5mL of DMF, followed by addition of40l L of AgNO3aqueous (0.5mol/L).After being immediately sonicated for about2min,the mixture was placed in microwave oven for2min(powder:750W).The AgNPs/GN dispersion was obtained after being sonicated for 10min.The AgNPs/GN nanocomposites were collected by centrifugation and washed by DMF. The resulting precipitates were redispersed in water for characterization and further use.
Results and discussion
Figure1shows the Raman spectra of GO and AgNPs/ GN composites thus formed.It is established that graphene exhibits two characteristic main peaks:one D band at*1350cm-1arising from a breathing mode of j-point photons of A1g symmetry and one G band at1575cm-1,arising from the?rst order scattering of the E2g phonon of sp2C atoms(Tung et al.2009).In our present study,it is seen that both GO and AgNPs/GN exhibit a D band at1350cm-1 and a G band at1603cm-1and AgNPs/GN has a higher relative intensity of D to G band(0.94)than that of GO(0.80),demonstrating the formation of new graphitic domains after the microwave irradiation(Li et al.2010).Figure1inset shows the photographs of GO–AgNO3mixture before(left)and after(right)the microwave irradiation,revealing a distinct color change from pale-yellow to black.Such observation provides another piece of evidence to support the reduction of GO during the microwave irradiation.
Figure2shows the XRD patterns of GO and as-formed AgNPs/GN.Graphite powder shows a sharp (002)peak at26.4°with a typical inter-spacing of 3.34A?(data not shown)(McAllister et al.2007); however,it is found that GO exhibits a strong peak at 10.02°corresponding to the(002)inter-planar spac-ing of8.2A?(Fig.2a),indicating graphite has been successfully oxidized by Hummers method
(Zhu
Fig.1Raman spectra of GO(a)and AgNPs/GN(b). Inset photographs of GO–AgNO3mixture before(left) and after(right)microwave irradiation
et al.2010a,b).After the microwave irradiation,the peak at10.02°disappears(Fig.2b),con?rming the successful reduction of GO(Nethravathi and Raja-mathi2008).Note that another new peaks corre-sponding to(111),(200),and(220)facet of Ag crystal is also observed at38.3°,44.5°,and64.6°, indicating the formation of metallic Ag(Luo et al. 2005).Note that another two new peaks centered at 24.8°and28.1°are observed,which are not corre-sponding to either AgNO3or Ag2O(Fang et al. 2009).Because there are many–COO-groups at the edge of GN(Kim et al.2010),some Ag(I)species are coordinated by–COO-to form coordinated species which may be responsible for these two peaks.Figure S1shows the FT-IR spectra of GO and AgNPs/GN.It is seen that GO exhibits two peaks at1198and 1722cm-1associated with C–O–C and C=O groups. In contrast,such two peaks of AgNPs/GN is observed at1101and1660cm-1,which are shifted97and 66cm-1compared to GO,because the carbonyl of the AgNPs/GN probably catch part electrons cloud of the Ag?,indicating that the Ag?coordinate to COO-(Xu et al.2009).These observations suggest that there are both metallic Ag and Ag?adsorbed on GN.
To further con?rm the formation of composites structure,the samples were also investigated by XPS technique which has been proven to be a signi?cant measure for observation the inner structure of C for carbon-based materials.Figure3shows the C1s XPS spectra of GO and AgNPs/GN,respectively.The C1s spectra of GO and AgNPs/GN could be deconvoluted into four peaks at284.5,285.6,286.6,and288.4eV, which are associated with C–C,C–OH,C(epoxy/ alkoxy),and C=O,respectively(Park et al.2008).The intensity of all the peaks of carbon to oxygen decreased dramatically after the microwave irradia-tion,suggesting about65%of oxygen-containing functional groups are successfully removed from GO.
Figure4shows the Ag3d XPS spectrum of AgNPs/GN.It was reported that the metallic Ag3d peaks are centered at373.9and367.9eV,respec-tively(Pol et al.2002).In contrast,Ag?containing materials show3d peaks at369.6and375.8eV(Cai et al.1998).It is obviously seen the composites thus formed exhibit two strong peaks centered at374.3 and368.2eV,respectively(Tian et al.2010).This observation suggests that there are both metallic Ag and Ag?in AgNPs/GN,which is agreement with the result of XRD.
The formation of AgNPs/GN was also evidenced by UV–vis spectrum of the DMF dispersion of the nanocomposites as shown in https://www.doczj.com/doc/a29042470.html,pared to the spectra of GO and GN,a strong adsorption peak at 452nm assigned to AgNPs is observed,suggesting the formation of AgNPs(Luo et al.2005).Further-more,the absorbance of GN in the spectral region between400and800nm is stronger than that of GO, further indicating the reduction of GO by microwave irradiation.The formation of AgNPs/GN composites was further evidenced by TEM observation as shown in Fig.6.It is clearly seen that the GN has been decorated with small AgNPs about several nanome-ters in diameter,and almost all the AgNPs were distributed uniformly on the GN substrate.Scheme1 represents a scheme(not to scale)to illustrate the formation of AgNPs/GN composites from GO and AgNO3with the use of DMF as reducing and dispersing agent.It should be noted that the
formation
Fig.2XRD patterns of GO(a)and AgNPs/GN(b)
of AgNPs and graphene from AgNO3and GO can be attributed to the direct redox between DMF and AgNO3and GO,because there is no other reducing agent in this system.Indeed,DMF has been used as a good reducing agent for preparation of AgNPs (Pastoriza-Santos and Liz-Marza′n2002a)and graph-ene(Murugan et al.2009),respectively.It is expected that DMF can decompose into CO and dimethylamine due to the high temperature([156°C)formed under microwave irradiation,where CO can
effectively
Fig.4Ag3d XPS spectrum of AgNPs/GN
reduce GO and AgNO3into AgNPs/GN nanocom-posites(Ai et al.2011).The formation of AgNPs may be also proposed as that Ag?was reduced to Ag0 along with formation of Me2NCOOH from DMF (Pastoriza-Santos and Liz-Marza′n2002b).It also should be mentioned that the resulting dispersion of AgNPs/GN is very stable,suggesting DMF serves as a good dispersing agent for GN and GN-based materials (Park et al.2009;Wang et al.2009).
It is well known that the AgNPs exhibit high catalytic activity for reduction of H2O2(Lu et al.2011; Tian et al.2011;Song et al.2009;Welch et al.2005).As a demonstration of application of such AgNPs/GN nanocomposites,they were deposited on a bare GCE surface to test their catalytical performance for H2O2 reduction.Figure7shows cyclic voltammograms (CVs)of a bare GCE,and a AgNPs/GN modi?ed GCE(designated as AgNPs/GN/GCE)in N2saturated 0.2M PBS at pH6.5in the presence of1mM H2O2 (scan rate:0.02V/s).It is obviously seen that the response of the bare GCE toward the reduction of H2O2is pretty weak.In contrast,the AgNPs/GN/GCE exhibits a remarkable catalytic current peak about 40l A in intensity at-0.36V vs.Ag/AgCl.
These
Fig.6TEM image of AgNPs/GN
Scheme1A scheme(not to scale)to illustrate the formation of AgNPs/GN from GO and AgNO3with the use of DMF as a reducing agent and solvent
Fig.7Cyclic
voltammetrys(CVs)of a
bare GCE(a),and a AgNPs/
GN/GCE(b)in N2saturated
0.2M PBS at pH6.5in the
presence of1mM H2O2
(scan rate:0.02V/s)
Fig.8Typical steady-state
response of the AgNPs/GN/
GCE to successive injection
of H2O2into the stirred N2
saturated0.2M PBS at pH
6.5.Inset calibration curve
(applied potential:-0.3V)
observations indicate that the AgNPs/GN nanocom-posites exhibit notable catalytic ability for H2O2 reduction.
Figure8shows the typical current–time plot of the AgNPs/GN/GCE in N2-saturated0.2M PBS buffer (pH6.5)on successive step change of H2O2concen-trations under optimized conditions.When an aliquot of H2O2was added into the stirring PBS solution, AgNPs/GN/GCE responded rapidly to the substrate and the current rose steeply to reach a stable value.At the applied potential of-0.30V,the cathode current of the sensor increased dramatically and achieved 95%of the steady-state current within2s,revealing a fast amperometric response behavior.The inset shows the calibration curve of the sensor.The linear detection range is estimated to be from0.1to 100mM(r=0.999),and the detection limit is estimated to be0.5l M at a signal-to-noise ratio of3. Conclusions
Microwave irradiation has been employed to prepare AgNPs/GN composites by microwave heating of a DMF solution of GO and Ag salts in the absence of an extra reducing agent.The detection of H2O2 without using enzyme in the electrode modi?ed by AgNPs/GN nanocomposites has also been demon-strated and it revealed that the AgNPs contained therein exhibit notable catalytic activity toward the reduction of H2O2.Our present?ndings provide us a low-cost approach to the facile production of nano-particles/GNs composites on a large scale for applications.
Acknowledgment This work was supported by National Basic Research Program of China(No.2011CB935800). References
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5.6 RAPID程序指令与功能简述5. 6.1 程序执行的控制 1. 程序的调用 指令说明 ProcCall 调用例行程序 CallByVar 通过带变量的例行程序名称调用例行程序 RETURN 返回原例行程序 2. 例行程序内的逻辑控制 指令说明 Compact IF 如果条件满足，就执行下一条指令 IF 当满足不同的条件时，执行对应的程序 FOR 根据指定的次数，重复执行对应的程序 WHILE 如果条件满足，重复执行对应的程序 TEST 对一个变量进行判断，从而执行不同的程序 GOTO 跳转到例行程序内标签的位置 Lable 跳转标签 3. 停止程序执行 指令说明 Stop 停止程序执行 EXIT 停止程序执行并禁止在停止处再开始 Break 临时停止程序的执行，用于手动调试SystemStopAction 停止程序执行与机器人运动 ExitCycle 中止当前程序的运行并将程序指针PP复位到主程序的第一条指令。如果选择了程序连续运行模式，程序将从主程序的第一句重新执行。 5.6.2 变量指令 1. 赋值指令 指令说明:= 对程序数据进行赋值 2. 等待指令 指令说明 WaitTime 等待一个指定的时间，程序再往下执行 WaitUntil 等待一个条件满足后，程序继续往下执行
WaitDI 等待一个输入信号状态为设定值 WaitDO 等待一个输出信号状态为设定值 3. 程序注释 指令说明 Comment 对程序进行注释 4. 程序模块加载 指令说明 Load 从机器人硬盘加载一个程序模块到运行内存 UnLoad 从运行内存中卸载一个程序模块 Start Load 在程序执行的过程中，加载一个程序模块到运行内存中 Wait Load 当Start Load使用后，使用此指令将程序模块连接到任务中使用CancelLoad 取消加载程序模块 CheckProgRef 检查程序引用 Save 保存程序模块 EraseModule 从运行内存删除程序模块 5. 变量功能 指令说明 TryInt 判断数据是否是有效的整数 功能说明 OpMode 读取当前机器人的操作模式 RunMode 读取当前机器人程序的运行模式 NonMotionMode 读取程序任务当前是否无运动的执行模式 Dim 获取一个数组的维数 Present 读取带参数例行程序的可选参数值 IsPers 判断一个参数是不是可变量 IsVar 判断一个参数是不是变量 6. 转换功能 指令说明 StrToByte 将字符串转换为指定格式的字节数据 ByteToStr 将字节数据转换为字符串 5.6.3 运动设定 1. 速度设定 功能说明 MaxRobSpeed 获取当前型号机器人可实现的最大TCP速度
RAPID参考手册 指令 张建辉韩鹏
1.指令1.1．AccSet—降低加速度 用途： 当处理较大负载时使用AccSet指令。它允许减慢加速度和减速度，使机器人有一个更平滑的运动。 该指令只能在主任务T_ROB1中使用，或者如果处于多运动系统，在Motion任务中。 基本范例： AccSet的基本范例说明如下。 例1AccSet 50，100； 加速度备限制到正常值的50%。 例2AccSet 100，50； 加速度斜线限制到正常值的50%。 项目： AccSet Acc Ramp Acc： 数据类型：num（数值） 加速度和减速度作为正常值的百分比。100%对应最大加速度。最大值：100%。输入值<20%则给出最大加速度的20%。 Ramp 数据类型：num（数值） 加速度和减速度的增加作为正常值的百分比的比例（如图）。通过减小这个数值可以限制震动。100%对应最大比例。最大值：100%，输入值<10%则给出最大比例的10%。 下图说明减小加速度可以平滑运动。 加速度加速度加速度 时间时间时间AccSet 100，100 正常加速度AccSet 30，100 AccSet 100，30 程序执行： 该加速度值应用到机器人和外部轴，直到一个新的AccSet指令执行。 缺省值（100%）在以下情况是自动设置： ●冷启动 ●加载了新的程序 ●从头开始执行程序时 语法： AccSet [AccSet “：=”]<数值表达式（IN）>“，”[Ramp “：=”]<数值表达式（IN）>“；” 相关信息：
1.2．ActUnit—激活一个机械单元 用途： ActUnit用来激活一个机械单元。 例如当使用普通驱动单元的时候，它可以用来决定哪一个单元被激活。 该指令只能在主任务T_ROB1中使用，或者如果处于多运动系统，在Motion任务中。 基本范例： ActUnit的基本范例说明如下： 例1 ActUnit orbit_a； orbit_a机械单元的激活。 项目： AccUnit MechUnit MechUnit： 机械单元 数据类型：mecunit（机械单元） 要激活的机械单元的名称。 程序执行： 当机器人的和外部轴的实际路径准备好以后，整个路径被清理并且特定的机械单元被激活。这意味着它被机器人控制和监视。 如果多个机械单元共享一个普通驱动单元，这些单元中的一个的激活，也将把该单元连接到普通驱动单元。限制： 如果在该指令之前有一个运动指令，那个指令的程序中必须带有停止点（区域数据fine），而不是一个通过点，否则将不能进行电源失败后的重启。 AccUnit指令不能在连接到以下任何特定的系统事件的RAPID程序中执行：电源上电，停止，Q停止，重启或者复位。 语法： ActUnit [MechUnit “：=”]<机械单元变量（V AR）>“；” 相关信息：
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全力满足教学需求，真实规划教学环节 最新全面教学资源，打造完美教学模式 ABB[a]-J-6ABB机器人的程序编程 6.1任务目标 掌握常用的PAPID程序指令。 掌握基本RAPID程序编写、调试、自动运行和保存模块。 6.2任务描述 ◆建立程序模块test12.24，模块test12.24下建立例行程序main和Routine1，在main程序下进行运动指 令的基本操作练习。 ◆掌握常用的RAPID指令的使用方法。 ◆建立一个可运行的基本RAPID程序，内容包括程序编写、调试、自动运行和保存模块。 6.3知识储备 6.3.1程序模块与例行程序 RAPID程序中包含了一连串控制机器人的指令，执行这些指令可以实现对机器人的控制操作。 应用程序是使用称为RAPID编程语言的特定词汇和语法编写而成的。RAPID是一种英文编程语言，所包含的指令可以移动机器人、设置输出、读取输入，还能实现决策、重复其他指令、构造程序、与系统操作员交流等功能。RAPID程序的基本架构如图所示： RAPID程序的架构说明： 1）RAPID程序是由程序模块与系统模块组成。一般地，只通过新建程序模块来构建机器人的程序，而系统模块多用于系统方面的控制。 2）可以根据不同的用途创建多个程序模块，如专门用于主控制的程序模块，用于位置计算的程序模块，
用于存放数据的程序模块，这样便于归类管理不同用途的例行程序与数据。 3） 每一个程序模块包含了程序数据、例行程序、中断程序和功能四种对象，但不一定在一个模块中都 有这四种对象，程序模块之间的数据、例行程序、中断程序和功能是可以互相调用的。 4） 在RAPID 程序中，只有一个主程序main ，并且存在于任意一个程序模块中，并且是作为整个RAPID 程序执行的起点。 操作步骤： 1. 2. 3.4.
abb机器人-rapid程序指令与功能简述第5章 ABB机器人的程序编程 5.6 RAPID程序指令与功能简述 5.6.1 程序执行的控制 1. 程序的调用 指令说明 ProcCall 调用例行程序 CallByVar 通过带变量的例行程序名称调用例行程序 RETURN 返回原例行程序 2. 例行程序内的逻辑控制 指令说明 Compact IF 如果条件满足，就执行下一条指令 IF 当满足不同的条件时，执行对应的程序 FOR 根据指定的次数，重复执行对应的程序 WHILE 如果条件满足，重复执行对应的程序 TEST 对一个变量进行判断，从而执行不同的程序 GOTO 跳转到例行程序内标签的位置 Lable 跳转标签 3. 停止程序执行 指令说明 Stop 停止程序执行 EXIT 停止程序执行并禁止在停止处再开始
Break 临时停止程序的执行，用于手动调试 SystemStopAction 停止程序执行与机器人运动 中止当前程序的运行并将程序指针PP复位到主程序的第一条指令。ExitCycle 如果选择了程序连续运行模式，程序将从主程序的第一句重新执行。 5.6.2 变量指令 1. 赋值指令 指令说明 := 对程序数据进行赋值 2. 等待指令 指令说明 WaitTime 等待一个指定的时间，程序再往下执行 WaitUntil 等待一个条件满足后，程序继续往下执行 第 1 页共 1 页 第5章 ABB机器人的程序编程 指令说明 WaitDI 等待一个输入信号状态为设定值 WaitDO 等待一个输出信号状态为设定值 3. 程序注释 指令说明 Comment 对程序进行注释 4. 程序模块加载 指令说明 Load 从机器人硬盘加载一个程序模块到运行内存 UnLoad 从运行内存中卸载一个程序模块