oxygen reduction ability of metal

第45卷第6期燕山大学学报Vol.45No.62021年11月Journal of Yanshan UniversityNov.2021㊀㊀文章编号:1007-791X (2021)06-0471-11g-C 3N 4及其复合材料电催化还原反应的研究进展黄㊀浩∗,刘昊权,任兴辉,韩㊀雨,姚文博(燕山大学亚稳材料制备技术与科学国家重点实验室,河北秦皇岛066004)㊀㊀收稿日期:2021-01-26㊀㊀㊀责任编辑:王建青基金项目:国家自然科学基金资助项目(51771165);河北省自然科学基金资助项目(E2020203123)㊀㊀作者简介:∗黄浩(1977-),男,湖北崇阳人,博士,研究员,主要研究方向为无机复合材料的电催化性能,Email:huanghao@㊂摘㊀要:石墨相氮化碳(g-C 3N 4)是一种无机非金属聚合半导体材料,其原料来源广泛,制备工艺简单㊁成本低廉,并且具有优异的电子能级结构和良好的稳定性,因而成为电催化领域的研究热点之一㊂本文综述了g-C 3N 4及其复合材料电催化还原反应的研究现状,首先介绍了不同形貌g-C 3N 4的电催化性能,接着列举了贵金属/g-C 3N 4㊁过渡金属/g-C 3N 4㊁非金属/g-C 3N 4复合材料电催化剂的研究进展,最后指出了该研究方向目前仍然存在的问题,并对g-C 3N 4基电催化剂未来的发展方向进行了展望㊂关键词:电催化;g-C 3N 4;复合材料;还原反应中图分类号:O646㊀㊀文献标识码:A㊀㊀DOI :10.3969/j.issn.1007-791X.2021.06.0010㊀引言人类步入工业社会以来,对煤炭㊁石油等传统化石燃料的消耗与日俱增,能源危机和环境问题日益严重,并且如今人类社会的能源需求仍在不断增长,传统的化石燃料储量已经略显疲态㊂为应对上述问题,人类有必要寻找清洁㊁可再生㊁高效的能源替代化石燃料,科研人员为开发绿色清洁能源做出了巨大努力,开发绿色可再生能源已成为当今世界的热门话题[1-5]㊂其中,氢能㊁燃料电池㊁电催化还原二氧化碳㊁电催化氮还原合成氨等能源存储与转换方面的研究备受关注[6-7]㊂但在此类能源转换装置中,往往涉及动力学缓慢的电化学反应,为了使电化学反应以所需要的速度进行,通常会产生较大的过电位,造成大量的能量浪费㊂电催化剂能加快电极㊁电解质界面上的电荷转移速度,加速电化学反应过程,达到最大的能量利用率㊂因此,开发高效的电催化剂具有重要意义[8-10]㊂由于贵金属最外层的d 轨道属于未填满状态,其特殊的电子排布状态使其极易吸附反应物分子成为催化活性中心,且具有良好的稳定性,因此贵金属仍被认为是最有效的电催化剂[11-13]㊂但贵金属储量稀缺㊁成本高昂[14-15],为解决此问题,科研人员主要从两方面进行研究:一是将贵金属与非贵金属材料复合,降低贵金属的使用量,提高利用率;二是开发非贵金属电催化剂,目前已经研制出过渡金属[16]㊁钙钛矿型[17]㊁金属碳化物[18]等多种电催化剂,取得了极大进展㊂石墨相氮化碳(g-C 3N 4)是一种无机非金属聚合半导体材料,具有优异的电子能级结构,在电催化过程中可以实现电子跃迁和转移,且化学结构独特,具有良好的热稳定性和化学稳定性[19-21]㊂目前g-C 3N 4已成功应用于传感器㊁催化剂载体㊁储能材料等电化学领域㊂但由于g-C 3N 4作为半导体材料,与贵金属相比导电性很差,直接用作电催化剂材料并不理想㊂因此,一般通过对g-C 3N 4形貌调控㊁元素掺杂和与其他材料构建复合材料等手段对其进行改性[22-27]㊂本文综述了近年g-C 3N 4及其复合材料电催化还原反应的研究进展,指出了目前仍然存在的问题,并对未来发展方向进行了展望,为开发高效㊁低成本的g-C 3N 4复合材料电催. All Rights Reserved.472㊀燕山大学学报2021化剂提供一定的参考㊂1㊀g-C 3N 4及其复合材料电催化还原反应的研究进展㊀㊀氮化碳是氮碳化物的一种同素异形体,其历史可追溯到1834年,由Berzelius 首次合成,被Liebig 命名为 melon [28-29],因此被认为是最古老的人工合成化合物之一㊂但是由于氮化碳具备化学惰性和难溶解性,使得科研人员对氮化碳材料的相关研究相对缓慢[30]㊂直到1996年,Teter 和Hemley 通过大量的理论计算,发现氮化碳具有五种晶相,分别为α相㊁β相㊁c 相㊁p 相和g 相[31-32],其中g-C 3N 4是软质相,在常温常压下具有良好的热稳定性和化学稳定性㊂g-C 3N 4是一种黄色粉末,具有类似石墨的层状结构,层与层之间以范德华力结合㊂在g-C 3N 4结构中,C㊁N 以sp 2杂化,并以σ键连接,剩下的电子形成弧电子对,以类似苯环的π键连接,通过末端的N 原子相连构成三嗪环或七嗪环[33](如图1所示[34])㊂Kroke 等根据密度泛函理论对g-C 3N 4的两种结构进行理论计算,结果表明以七嗪环为结构单元的g-C 3N 4在热力学上更为稳定,因此,g-C 3N 4的结构单元通常被认为是七嗪环[35-36]㊂g-C 3N 4具有3倍配位(类石墨)和2倍配位(吡啶类)氮原子,并且每个碳原子与3个氮原子键合,包括吡啶N 和石墨N,丰富的石墨N 和吡啶N 可提供较高的石墨化度和足够的活性位点[37],在电催化领域具有巨大的发展潜力㊂但与一般的碳材料不同的是,g-C 3N 4的导电性较差,且比表面积小,导致其电催化性能并不理想,是限制g-C 3N 4在电催化领域广泛应用的主要因素[38-40]㊂为了实现对g-C 3N 4的电催化性能的改性,科研人员做了大量研究㊂目前,已通过调控形貌或与贵金属㊁非贵金属材料复合等方法制备出了高效㊁稳定的电催化剂㊂图1㊀g-C 3N 4的两种结构类型Fig.1㊀Two structural types of g-C 3N 41.1㊀不同形貌g-C 3N 4电催化还原反应研究进展形貌对于半导体催化剂的催化性能有着很大的影响㊂通过改变㊁控制㊁调节g-C 3N 4的形貌,以期增大其比表面积,增多电催化反应的活性位点,达到提高g-C 3N 4电催化性能的目的㊂经过科研人员的不断探索,目前已经制备出g-C 3N 4纳米片[41-42]㊁g-C 3N 4纳米球[43]㊁g-C 3N 4空心微球[44]等多种形貌的g-C 3N 4电催化剂㊂张胜等[45]采用溶剂热法,通过控制反应时间,发现反应时间为12h 时产品形貌为不规则的块状;24h 时产品形貌为多孔片状;48h 时产品形貌为纤维网状结构,平均直径约为60nm;而反应96h 后纤维变粗,直径约72nm(如图2所示)㊂随后通过测定不同形貌样品的比表面积及阻抗,对比得出反应24h 所得的多孔片状g-C 3N 4的比表面积最高,是块状g-C 3N 4的8倍,且其阻抗值也最小㊂2016年Guo Shien 等人[46]合成了一种P 掺杂的g-C 3N 4六方微管,随后研究人员针对管状g-C 3N 4结构进行了大量研究,但由于制备管状g-C 3N 4方法较为苛刻,且形态混乱,因此Jiang Zhixiang 等人[47]在不使用模板的情况下,制备了具有规则六边形形态的g-C 3N 4纳米管㊂该课题组首先以g-C 3N 4为原料经过热缩聚反应生成六边形棒状中间体,再将中间体进一步进行热缩聚反应生成规则六边形纳米管㊂由于电子可以沿管状结构. All Rights Reserved.第6期黄㊀浩等㊀g-C 3N 4及其复合材料电催化还原反应的研究进展473㊀沿Z 轴转移,从而将电子的传输限定在特殊的维度上,减少了电子在诸多颗粒晶面处的传输阻力,有利于电子转移,导电性得到提升,因此电催化析氢性能(HER)得到了改善㊂之后Jiang Zhixiang 等人在六边形纳米管上沉积了Pt,析氢性能明显改善,Tafel 斜率明显降低,表明具有更快的反应动力学,具有良好的HER 催化性能㊂图2㊀不同合成时间所制备的g-C 3N 4的SEM 图像Fig.2㊀SEM images of as-prepared g-C 3N 4at different reaction times㊀㊀将可再生能源与CO 2电催化还原技术结合,将大气中的CO 2转化为CO㊁HCOOH㊁CH 3OH㊁CH 4等产物,能够实现CO 2的循环转化,减少大气中CO 2的累积,同时降低对传统化石能源的依赖,因此成为近年来的研究热点[48-49]㊂CO 2的电还原的反应途径通常涉及3个相互作用过程:CO 2吸附㊁电荷转移和产物解离,其中前两步是电子和质子转移的电化学反应,第三步是产物从催化剂表面释放的非电化学过程㊂近期,Zhou Chen 等人[50]提出了一种N 空位工程激活碳活性中心,以促进CO 2电还原(CO 2RR)的新方法,制备了N-空位工程化的g-C 3N 4(DCN)㊂N-空位工程化的g-C 3N 4上将CO 2还原为CH 4的机理如图3所示(∗表示激活的位点㊂黄色代表碳,蓝色代表氮,红色代表氧,绿色代表氢)㊂由于围绕N 空位的C 原子由三配位转化为二配位,提高了对反应过程中关键中间体的吸附(∗CO),降低了CO 2还原为CH 4的活化能垒,表现出良好的CO 2电还原活性㊂1.2㊀贵金属/g-C 3N 4复合材料电催化还原反应研究进展㊀㊀由于贵金属具有优良的导电性,且耐酸碱程度高㊁稳定性好,故而贵金属依然是最有效的电催化还原反应催化剂,但贵金属高昂的成本限制了其工业化应用㊂因此,目前许多关于贵金属催化剂的研究都集中在降低贵金属的使用量㊁提高贵金属的利用效率上[51],如将贵金属与非贵金属形成合金[52-53]㊁贵金属与非贵金属或非金属复合形成复合材料[54]等㊂由于g-C 3N 4结构中重复的s-三嗪单元的存在可以使其更容易与纳米粒子配位形成复合材料,这种强配位作用有助于电子传输,且g-C 3N 4具有良好的化学稳定性和较高的吡啶氮含量,有助于提升电催化性能[55-57]㊂因此将贵金. All Rights Reserved.474㊀燕山大学学报2021属与g-C 3N 4复合形成复合材料,是目前能源领域的研究热点之一,贵金属/g-C 3N 4复合材料对多种电催化还原反应表现出良好的催化性能㊂图3㊀CO 2RR 在N 2V-CN 上形成CH 4的反应能谱(插图为优化的原子结构)Fig.3㊀Calculated reaction energy profiles for CO 2RR to form CH 4on N 2V-CN (insets are optimized atomic structures)㊀㊀2018年,Jiang Binbin 等人[57]通过简便的溶剂热法,将Ir 纳米粒子锚固在g-C 3N 4/氮掺杂石墨烯表面(Ir /g-C 3N 4/NG)㊂Ir 纳米粒子和NG 可以起到改善g-C 3N 4导电性的作用,同时g-C 3N 4可以提高Ir 纳米粒子的分散性,防止聚集,从而暴露出更多的活性位点㊂因此该催化剂在0.5M H 2SO 4电解液中,表现出与贵金属基准催化剂(质量分数为20%的Pt /C)相当的HER 活性和优良的稳定性㊂此外,Nimai Bhandary 等人[58]通过直接液态热处理法,合成了氧化石墨烯上负载Ag 纳米颗粒修饰的g-C 3N 4催化剂(Ag /g-C 3N 4@GO)㊂该催化剂在碱性电解液中表现出优异的ORR 活性,在1600rpm下极限电流密度为5.1mA /cm 2,且具有较小的Tafel 斜率(117mV /dec ),远低于纯g-C 3N 4(155mV /dec)㊂Zhao Siqi 等人[59]将碳量子点和金纳米颗粒负载在g-C 3N 4上,制备了Au-CDots-C 3N 4三元电催化剂,用于将CO 2还原成CO㊂在Au 负载量为4%(质量分数)时,Au-Cdots-C 3N 4在-0.5V(vs.RHE)的电势下表现出较高的法拉第效率(79.8%)和较低的过电势(190mV)㊂DFT计算表明,Au-Cdots-C 3N 4催化剂对CO 2RR 的高活性源自于Au 纳米颗粒㊁CDots 和g-C 3N 4之间的协同作用,CDots 对H +和CO 2的强吸附能力㊂除单一贵金属与g-C 3N 4复合外,由于两种金属之间存在协同效应,能够进一步改善催化剂的性能,因此研究人员对双金属/g-C 3N 4复合材料做了深入研究㊂Roshan Nazir 等人[55]以g-C 3N 4/Ag 为前驱体,通过电交换技术在g-C 3N 4表面合成了多种空心双金属粒子(AgPd㊁AgPt㊁AgAu),以g-C 3N 4/AgPt 为例,材料合成机理如式(1)㊁(2)所示㊂C 3N 4+Ag ++NaBH 4ңC 3N 4/Ag(1)C 3N 4/Ag(s)+PtCl -(sol)ңC 3N 4/AgPt(s)+Ag +(sol)+4Cl -(2)得益于双金属合金带来的表面修饰和金属之间的强协同效应,以及该合金纳米颗粒的空心结构使活性位点更多地暴露于电解质,双金属/g-C 3N 4催化剂均表现出比单金属C 3N 4/Ag 更优异的HER 性能㊂双贵金属/g-C 3N 4催化剂的研究不仅限于HER,Feng Jiuju 等人[60]通过简单的一锅水法合成了负载在g-C 3N 4上的AuPd 纳米团簇(AuPd NCs /g-C 3N 4)㊂该催化剂在ORR 中显示出比商业Pt /C 和Pd /C 更正的起始电位(0.98V vs.RHE)和半波电位(1.09V vs.RHE),及更大的极限电流密度(5.4mV /cm 2),显示出优异的ORR 性能㊂同时该催化剂还表现出与商业Pt /C 相差无几的HER 性能和极低的Tafel 斜率(47mV /dec),表明该催化剂是一种性能优异的双功能电催化剂㊂1.3㊀非贵金属/g-C 3N 4复合材料电催化还原反应研究进展㊀㊀将g-C 3N 4与贵金属复合形成复合材料,固然. All Rights Reserved.第6期黄㊀浩等㊀g-C3N4及其复合材料电催化还原反应的研究进展475㊀可以提升电催化性能,但从长远里看,贵金属/g-C3N4复合材料的发展及应用还是受制于贵金属极为有限的储量,成本问题依然存在[61]㊂因此,开发非贵金属/g-C3N4电催化剂成为目前的研究热点之一,研究人员研究了不同非贵金属/g-C3N4材料的电催化还原反应性能(表1~3)㊂表1㊀非贵金属/g-C3N4复合材料的电催化氧还原性能Tab.1㊀Electrocatalytic oxygen reduction performance of non-precious metal/g-C3N4composite电催化剂半波电位/(V vs.RHE)Tafel斜率/(mV/dec)稳定性实验电解液/(mol/L)参考文献Fe-g-C3N40.8873半波电位损失6mv(12h)0.1KOH[63] C3N4/Ti3C20.79 无明显衰减(40000s)0.1KOH[67] Cu-g-C3N40.7979.7半波电位损失12mV(12h)0.1KOH[20] Co-C3N4/CNT0.8552.8半波电位损失10mv(3000cycles)0.1KOH[56] Co-C3N4/C0.82 无明显衰减(3000cycles)0.1KOH[74] Co3O4-C3N4/rGO0.8187.2电流密度保持率为94.71%(20000s)0.1KOH[75] Co3O4@C3N4/NG0.8482.1电流密度保持率为97.6%(12000s)0.1KOH[69]表2㊀非贵金属/g-C3N4复合材料的电催化析氢性能Tab.2㊀Electrocatalytic hydrogen evolution performance of non-precious metal/g-C3N4composite电催化剂过电位/(mV@10mA/cm2vs.RHE)Tafel斜率/(mV/dec)稳定性实验电解液/(mol/L)参考文献Co-SCN/RGO15094电势保持稳定(20h) 1.0KOH[76] Ni/g-C3N4222128电势保持稳定(12h)0.5H2SO4[77] CNQDs@G11053电流密度保持稳定(10h)0.5H2SO4[72] PCN@N-graphene8549.1 0.5H2SO4[71] C3N4@MoN11057.8电流密度保持稳定(1000cycles) 1.0KOH[78] Cu-C3N439076电流密度保持稳定(43h)0.5H2SO4[79] MoS2/g-C3N428063 0.5H2SO4[80] Cu2O/g-C3N414855 1.0NaOH[81]表3㊀非贵金属/g-C3N4复合材料的电催化氮还原性能Tab.3㊀Electrocatalytic nitrogen reduction performance of non-precious metal/g-C3N4composite电催化剂NH3产率/(μg㊃h-1㊃mg-1)法拉第效率最佳电位(V vs.RHE)电解液/(mol/L)参考文献MoS2/g-C3N418.517.8%-0.30.1HCl[68]MoS2/g-C3N419.86 6.87%-0.50.1Na2SO4[83]S-NV-C3N432.714.1%-0.40.5LiClO4[73]W@g-C3N4 -0.35 [66]CNT@C3N4-Fe&Cu9.8634%-0.8 [82] . All Rights Reserved.476㊀燕山大学学报20211.3.1㊀过渡金属/g-C3N4复合材料电催化还原反应研究进展㊀㊀在非贵金属中,过渡金属成本低廉,且具有良好的催化活性和稳定性,成为最有希望的贵金属替代品之一[62],引起了科研人员极大的研究兴趣㊂Subhajit Sarkar等人[63]通过简便的一步热聚合法制备了Fe掺杂的g-C3N4(Fe-g-C3N4)㊂由XPS (图4(a))确定了其存在大量的Fe-N x活性位点,因此该催化剂表现出比Pt/C更正的起始电位和半波电位(图4(b)),具有优良的ORR性能㊂ORR反应有四电子途径(式(3))和二电子途径(式(4)~(5))两种:O2+2H2O+4e-ң4OH-(3)O2+H2O+2e-ңHO-2+OH-(4)HO-2+H2O+2e-ң3OH-(5)二电子途径会生成具有腐蚀性的H2O2,缩短电池寿命㊂四电子途径为迅速㊁高效的一步反应过程,被视为理想的反应途径[64]㊂该团队研究了在Fe-N x活性位点上的ORR反应机理(图4(c)),表明了反应中四电子的转移过程㊂电催化氮还原反应(NRR)作为一种绿色环保㊁能耗低并且具有可持续性的合成氨方法,吸引了越来越多的关注㊂一般认为,NRR有3种主要的反应途径:解离过程㊁缔合远端反应过程㊁缔合交替反应过程[65]㊂在解离过程中,N2分子吸附后与催化材料表面两个活性位点结合,NʉN键完全断裂,之后两个氮原子分别加氢生成NH3分子;在缔合远端反应过程中,N2分子吸附后与催化材料表面一个活性位点结合,NʉN键不完全断裂,远离催化材料表面活性位点的N原子先加氢生成一个NH3分子,剩下的N原子再加氢生成一个NH3分子;交替反应过程是指两个氮原子交替加氢生成两个NH3分子㊂Chen Zhe等人[66]通过DFT计算,评估了负载在g-C3N4上一系列过渡金属元素对氮还原反应(NRR)的催化活性,其中W@g-C3N4可以很好地抑制竞争性的析氢反应,表现出最佳的NRR活性,极限电位为-0.35V(vs.RHE)㊂图4㊀Fe-g-C3N4催化剂的N1s高分辨XPS光谱㊁LSV曲线及在碱性介质中的ORR反应机理Fig.4㊀High-resolution core-level N1s XPS spectra,LSV curves and ORR mechanism in an alkalinemedium of Fe-g-C3N4catalyst㊀㊀此外,过渡金属碳化物㊁硫化物㊁氧化物与g-. All Rights Reserved.第6期黄㊀浩等㊀g-C3N4及其复合材料电催化还原反应的研究进展477㊀C3N4复合材料也表现出优良的电催化还原性能㊂Yu Xuelian等人[67]通过界面静电相互作用,制备了g-C3N4/Ti3C2电催化剂㊂层状g-C3N4不仅可以充当Ti3C2纳米颗粒生长的基质,还有利于提高Ti3C2纳米颗粒的分散性,防止聚集;且由于g-C3N4与Ti3C2之间的电子耦合效应,增强了氧吸附性能和电荷分离,该催化剂表现出优良的ORR 性能㊂Chu Ke等人[68]将MoS2与g-C3N4复合到一起,制备了具有2D/2D MoS2/g-C3N4异质结构的复合材料㊂密度泛函理论计算表明,两种二维(2D)材料之间具有界面耦合相互作用㊂从g-C3N4到MoS2的界面电荷传输可以促进Mo边缘位点上关键中间体的稳定化(∗N2H),同时降低反应能垒,显著改善NRR性能,NH3产量为18.5μg㊃h-1㊃mg-1,在-0.3V(vs.RHE)时法拉第效率为17.8%㊂Wang Yanqiu等人[69]通过煅烧-水热法,将g-C3N4包裹的Co3O4纳米颗粒负载在N掺杂石墨烯上(Co3O4@g-C3N4/NG)㊂g-C3N4可以保护Co3O4活性位点,从而提高稳定性,而NG充当锚定Co3O4@g-C3N4的导电基质,提高导电性㊂该催化剂在碱性溶液中表现出出色的ORR 活性,半波电位为0.846V(vs.RHE),并且具有优良的稳定性㊂1.3.2㊀非金属/g-C3N4复合材料电催化还原反应研究进展㊀㊀在过渡金属/g-C3N4电催化剂受到广泛关注的同时,非金属催化剂作为贵金属替代品之一,也表现出出色的电催化还原反应性能,展现出巨大的发展潜力㊂石墨烯作为一种具有代表性的非金属材料之一,因电子迁移率高㊁比表面积大等优点,在很多领域都表现出巨大的应用前景[70]㊂石墨烯/g-C3N4复合材料也被应用于电催化还原反应领域㊂2015年,Duan Jingjing等人[71]通过真空过滤法,将二维多孔g-C3N4纳米层与氮掺杂石墨烯集成在一起,形成了三维杂化膜(PCN@N-graphene)㊂这种三维异质结构有利于催化活性中心的暴露,具有高孔隙率和强大的机械灵活性,在酸性环境中表现出良好的HER性能和优异的耐久性㊂Zhong Haixia等人[72]将g-C3N4量子点均匀分散在石墨烯上(CNQDs@G)㊂g-C3N4的量子化可以提高电荷转移能力㊁增加活性位点,且该催化剂具有双协同效应:第一是分子内边缘位点与分子筛结构之间的协同效应;第二是g-C3N4量子点(CNQDs)与石墨烯(G)之间的协同效应㊂因此CNQDs@G表现出可与许多金属催化剂相媲美的HER活性㊂Chu Ke等人[73]在通过S掺杂剂填充g-C3N4中氮空位(NVs),制备了一种无金属的NRR催化剂(S-NV-g-C3N4)㊂密度泛函理论计算表明,填充S的催化剂可以打破比例关系,改善对NRR中间体的吸附作用,降低能垒㊂其中S含量为5.2%(原子分数)的S-NV-g-C3N4表现出最佳的NRR活性,NH3产量为32.7μg㊃h-1㊃mg-1,在-0.4V(vs.RHE)时法拉第效率为14.1%,大大优于原始的g-C3N4和含NV的g-C3N4㊂2㊀结论与展望g-C3N4具有独特的电子结构和优异的化学稳定性,在电催化领域表现出极大的发展潜力㊂本文综述了不同形貌g-C3N4以及各类g-C3N4基复合材料电催化剂的研究现状㊂为了进一步激发g-C3N4基电催化剂的催化活性,后续工作可以从以下几个方面开展:1)与MOFs材料复合㊂金属-有机框架(MOFs)是一种金属离子和有机配体配位形成的多孔晶体材料㊂与传统多孔材料相比,MOFs材料具有更大的比表面积和更强的吸附能力,在电催化领域有非常广阔的应用前景,但目前对于MOFs 与g-C3N4复合材料的研究还很少,后续可以围绕此点开展工作㊂2)利用第一性原理或密度泛函理论等手段,探究g-C3N4基复合材料电催化反应的机理,深入研究与其他材料复合后对g-C3N4电子结构的影响,挖掘电催化性能得到增强的深层原因,为后续实验提供理论指导㊂3)与稀土金属氧化物复合㊂目前对于g-C3N4基复合材料电催化剂的研究,主要是与贵金属㊁过渡金属㊁非金属碳材料的复合,还未见到与稀土金属氧化物复合的相关报道㊂稀土金属氧化物可以调节电子结构和氧空位浓度,具有良好的储氧和释放氧能力,因此,制备g-C3N4/稀土金属氧化物复合材料是提升氧电催化性能的有效方法之一㊂. 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All Rights Reserved.第6期黄㊀浩等㊀g-C 3N 4及其复合材料电催化还原反应的研究进展479㊀ J .Journal of Colloid and Interface Science 2020 558182-189.21 TONDA S KUMAR S BHARDWAJ M et al.g-CN /NiAl-LDH2D /2D hybrid heterojunction for high-performance photocatalyticreduction of CO 2into renewable fuels J .ACS Applied Materials &Interfaces 2018 10 3 2667-2708.22 吕慧茹.基于g-C 3N 4纳米复合材料的制备与性能研究 D .杭州 浙江理工大学 2017.LÜH R.Studies on synthesis characterization and properties of g-C 3N 4based nanocomposites D .Hangzhou Zhejiang Sci-TechUniversity 2017.23 LIU G NIU P SUN C H et al.Unique electronic structureinduced high photoreactivity of sulfur-doped graphitic C 3N 4 J .Journal oftheAmericanChemicalSociety 2010 13211642-11648.24 CHEN L ZHU D Y LI J T et al.Sulfur and potassium co-dopedgraphitic carbon nitride for highly enhanced photocatalytic hydrogen evolution J .Applied Catalysis B Environmental2020 273 119050-119058. 25 ABOUBAKR A E EIROUBY W M KHAN M D et al.ZnCr-CO 3LDH /ruptured tubular g-C 3N 4composite with increased specific surface area for enhanced photoelectrochemical water splittingJ .Applied Surface Science 2020 508 145100-145110.26 ÖZDOKUR K V IRAK B B EDEN C et al.Facile synthesis andenhanced photo-electrocatalytic performance of TiO 2nanotube /g-C 3N 4composite catalyst by a novel synthesis approach J .Optik 2020 206 164262-164274.27 WANG Y G LI Y G BAI X et al.Facile synthesis of Y-dopedgraphitic carbon nitride with enhanced photocatalytic performance J .Catalysis Communications 2016 84 179-182.28 FINA F CALLRAR S K CARINS G M et al.Structuralinvestigation of graphitic carbon nitride via XRD and neutrondiffraction J .Chemistry of Materials 2015 27 7 2612-2618.29 侯可禹.片状g-C 3N 4及特殊形貌Cu 2O 基复合材料制备及电化学研究 D .福州 福州大学 2015.HOU K Y.Preparation and electrochemical investigation for g-C 3N 4nanosheet composite and Cu 2O special morphologicalcomposite D .Fuzhou Fuzhou University 2015.30 杭梦婷 成杨 宋晓晴 等.石墨相氮化碳 g-C 3N 4 的制备及其在单原子电催化中的应用研究进展 J .化学世界 2019 60 4 193-198.HANG M T CHENG Y SONG X Q et al.Preparation of g-C 3N 4and application in single-atom electrocatalysis J .Chemical World 2019 60 4 193-198.31 李荣荣 王锐 宫红 等.高比表面积g-C 3N 4的制备及其改性研究进展 J .化工新型材料 2017 45 1 35-37.LI R R WANG R GONG H et al.Research progress on thepreparation and modification of high-surface-area graphitic carbonnitride J .New Chemical Materials 2017 45 1 35-37.32 TETER D M HEMLEY R J.Low-compressibility carbon nitrides J .Science 1996 271 53-55.33 陈婷婷.g-C 3N 4和其复合材料的制备及其性能研究 D .哈尔滨 哈尔滨工程大学 2017.CHEN T T.Preparation and properties of g-C 3N 4and itscomposites D .Harbin Harbin Engineering University 2017.34 ZHAO Y ZHANG J QU L T.Graphitic carbon nitride /graphenehybrids as new active materials for energy conversion and storage J .Chem Nano Mat 2015 1 5 298-318.35 KROKE E SCHWARZ M HORATH-BORDON E et al.Tri-s-triazine derivatives.part I.from trichloro-tri-s-triazine to graphiticC 3N 4structures J .New Journal of Chemistry 2002 26 5508-512.36 ZHENG Y LIN L H WANG B et al.Graphitic carbon nitridepolymers toward sustainable photoredox catalysis J .AngewandteChemie International Edition 2015 54 12868-12884.37 郭琦.g-C 3N 4基复合材料作为氧电极催化剂的研究与应用D .合肥 合肥工业大学 2019.GUO Q.Research and application of the g-C 3N 4-basedcomposites as oxygen electrode catalyst D .Hefei Hefei University of Technology 2019.38 PENG B LU Y LUO J et al.Visible light-activated self-poweredphotoelectrochemical aptasensor for ultrasensitive chloramphenicol detection based on DFT-proved Z-scheme Ag 2CrO 4/g-C 3N 4/graphene oxide J .Journal of Hazardous Materials 2021 401123395-123403.39 ZHAN T R TAN Z W WANG X J et al.Hemoglobin immobilizedin g-C 3N 4nanoparticle decorated 3D graphene-LDH networkDirect electrochemistry and electrocatalysis to trichloroacetic acid J .Sensors and Actuators B Chemical 2018 255 149-158.40 BUTT F K HAUENSTEIN P KOSIAHN M et al.An innovativemicrowave-assisted method for the synthesis of mesoporous two-dimensional g-C 3N 4 a revisited insight into a potential electrodematerial for supercapacitors J .Microporous and Mesoporous Materials 2020 294 109853-109860.41 SONG T ZHANG P Y WANG T T et al.Alkali-assistedfabrication of holey carbon nitride nanosheet with tunable conjugated system for efficient visible-light-driven water splitting J .Applied Catalysis B Environmental 2018 224 877-885.42 SULIMAN M A SULIMAN M H ADAM A et al.Interfacialcoupling of amorphous cobalt boride with g-C 3N 4nanosheets for superior oxygen evolution reaction J .Materials Letters 2020268 127593-157596.43 LIN B XUE C YAN X Q et al.Facile fabrication of novel SiO 2/g-C 3N 4core-shell nanosphere photocatalysts with enhanced visible light activity J .Applied Surface Science 2015 357346-355.44 ZHAO Z L WANG X L SHU Z et al.Facile preparation ofhollow-nanosphere based mesoporous g-C 3N 4for highly enhanced. All Rights Reserved.。

附录5Ferrous MetalsMetals are divided into two general groups: ferrous metals and nonferrous metals. Ferrous metals are those metals whose major element is iron. The major types of ferrous metals arc irons, carbon steels, alloy steels and tool steels.IronThe iron ore which we find in the earth is not pure. It contains some impurities which we must remove by smelting. The process of smelting consists of heating the ore in a blast furnace with coke and limestone, and reducing it to metal. Blasts of hot air enter the furnace from the bottom and provide the oxygen which is necessary for the reduction of the ore, The ore becomes mohen, and its oxide combines with carbon kom the coke. The non-metallic constituents of there combine with the limestone to form a liquid slag. This floats on top of the molten iron, and passes out of the furnace through a tap. The metal which remains is pig-iron, and consists of approximately 93 percent iron, 5 percent carbon, and 2 percent impurities.Remehing pig iron and scrap iron in a furnace to remove some of the impurities produces cast iron. The type, or grade, of cast iron is determined by the extent of refining, the amounts of pig iron and scrap iron, and the methods used to cast and cool the metal.The three primary types of cast iron are gray cast iron, white cast iron, and malleable iron.Gray cast iron is primarily used for cast frames, automobile engine blocks, handwheel, and east housings. White cast iron is hard and wear resistant and is used for parts such as train wheels. Malleable cast iron is a tough material used for tools such as pipes and wrenches. Generally, cast irons have very good compressive strength, corrosion resistance, and good machinability. The main disadvantage of cast iron is its natural brittleness.Carbon SteelCarbon steel is made from pig iron that has been refined and cleaned of most impurities. Most of the original carbon in the metal is burned out during the refining process. Measured amounts of carbon are then added to the molten metal to produce the exact grade of carbon steel desired. After the steel is poured into ingots and allowed to cool, it is usually sent to a rolling mill to be rolled and formed into specific shapes.The three principal types of carbon steel used in industry are low, medium, and high carbon steel. The percentage of carbon :is the most important factor in determining the mechanical properties of each type of carbon steel. :Low carbon contains between 0. 05% and O. 30% carbon and is primarily used for parts that do not require great strength. Typical uses of low carbonsteel include chains, bolts, screws, washers, nuts, pins, wire, shafting, and pipes. This metal is also known as machine steel, mild steel, and cold-rolled steel. Low carbon steel is tough, ductile material that is easily machined and welded. It is useful for parts that must be stamped or formed.Containing between 0. 30 and 0.50% carbon, medium carbon steel is used for parts that required great strength than is possible with low carbon steel, such as gears, crankshafts, machine parts and axles. Because this steel has higher carbon content, it can be heat-treated to increase both hardness and wear resistance. Medium carbon steel is a tough, hardenable metal that has good machinability and is easily welded.Containing between 0.50 and 1.70% carbon, high carbon steel is used for parts that require hardness and strength, such as files, knives, drills, razors, and woodworking tools. Due to their increased carbon content, high carbon steels can be heat-treated to make them harder and more wear resistant than low or medium carbon steels. Due to their great hardness, high carbon steels are often brittle.Alloy SteelsAlloy steels are basically carbon steels with elements added to modify of change the mechanical properties of the steel. All steels are alloy steels because each is a combination of elements, including carbon steel, a mixture of iron and carbon. To identify the two groups, one is called carbon or plain steel and the other is referred to as alloy steel.Alloying elements are added to the molten steel in measured amounts. The desired end product determines the elements and amounts added. The primary alloying elements and their effect on the steel are as follows: Boron —The hardenability of an alloy is increased by boron. Only very small amounts of boron are needed to increase the hardenability characteristics of the other elements in the alloy.Chromium — When used in small amount, chromium increases the depth hardness of the metal. The more chromium used, the better the alloy resists corrosion. Chromium is a principal element in stainless steels.Cobalt —Cobalt is added to an alloy to increase wear resistance and increase red hardness, which is the ability of a metal to maintain a cutting edge at elevated temperature. Cobalt is a valuable addition to some high-speed tool steels.Lead —By reducing the cutting friction, lead improves machinability. Leaded steels also have good weldability and formability.Manganese —Impurities in alloy steels are controlled by using manganese as a purifier and scavenger. When added in larger amount ( 1 to 15 percent) , manganese produces good hardness and wear resistance.Molybdenum — A tough alloy suitable for a wide range of high-strength applications, molybdenum steel permits good depth hardness and strength at elevated temperatures.Nickel —High-strength alloys resistant to both elevated temperaturesand corrosion are produced by nickel. When alloyed with molybdenum, nickel steel becomes a very tough alloy, which is often used for many aircraft parts. Larger amounts of nickel greatly add to the corrosion resistance of stainless steels.Phosphorus and Sulfur —Free-machining carbon steels are produced with phosphorus and sulfur. When alloyed with carbon steels, phosphorus and suffer produce alloys with excellent machining characteristics.Tungsten —When alloyed with steel, tungsten produces a variety of high-speed tool steels and adds hardenability and strength at elevated temperatures as well as high resistance to wear.Vanadium —A tough, fine-grained steel that acts as a cleanser and purifier to eliminate many of the impurities of steel is produced by vanadium.Tool SteelsTool steels are a special grade of alloy steels used for making a wide variety of tools. Depending on their composition, tool steels are highly resistant to wear, shocks, and heat. These alloys gener ally contain more carbon, tungsten, and cobalt than do the standard alloy steels, i41 Another principal difference between most alloy steels and tool steels is the control with which elements are added.Tool steels are made with much closer quality controls than are other alloy steels.铁类金属金属材料分为两种类型：铁类金属和非铁金属。

3.1.1. Metal-Based Catalysts For ORR .氧还原金属基催化剂。

3.1.1.1. Pt Catalysts.1 PT催化剂。

Among all of the pure metal ORR catalysts developedto date, Pt is the most wid ely us electrocatalyst for ORR.在所有的纯金属和催化剂的开发到目前为止，PT是最广泛使用的氧还原催化剂.The ORR performance of the Pt catalyst depends on itscrystallization, morphology, sh ape, and size.Pt催化剂ORR的性能取决于其结晶，形态，形状和尺寸。

found that the ORR activity on Pt(100) is much higher than thaton Pt(111) in a H2SO4 medium due to the different adsorptionrates for the sulfates to be adso rbed on these different rates for the sulfates to be adsorbed on these different f acets.发现Pt的ORR活性（100）明显高于在Pt（111）在硫酸介质中的硫酸盐率，由于不同的吸附对于被吸附在这些不同的平面上.Therefore , it is critical to control the shape and morphology of Pt nanoparticles因此，它是控制铂的形状和形态的关键纳米材料.In this context, Wang et al. synthesized monodisperse Pt nanocubes, showing aSpecific activity over 2 times as high as that of the commercial Pt catalyst.在此背景下，王等人。

氧化态势英文Oxidation SituationThe world we live in is a delicate balance of various chemical reactions, and one of the most crucial among them is the process of oxidation. Oxidation, a fundamental chemical reaction, plays a pivotal role in shaping the very fabric of our existence, from the air we breathe to the energy that powers our lives. In this essay, we will explore the intricacies of oxidation and its far-reaching implications on our planet and our daily lives.At its core, oxidation is a chemical reaction in which a substance loses electrons, resulting in an increase in its oxidation state. This process is ubiquitous in nature, occurring in everything from the rusting of metal to the cellular respiration that sustains life. The importance of oxidation cannot be overstated as it is integral to numerous essential processes that sustain our world.One of the most well-known examples of oxidation is the rusting of iron. When iron is exposed to air and moisture, it undergoes a series of chemical reactions that cause it to slowly deteriorate and transform into a reddish-brown substance known as iron oxide. Thisprocess not only affects the structural integrity of the metal but also has significant implications for industries that rely on iron-based materials. Engineers and architects must account for the effects of oxidation when designing structures, vehicles, and infrastructure to ensure their longevity and safety.Beyond the realm of industry, oxidation also plays a crucial role in the natural world. In the atmosphere, the process of oxidation is responsible for the formation of ozone, a gas that shields the Earth from the harmful effects of ultraviolet radiation. Ozone, created through the interaction of oxygen molecules and solar energy, acts as a protective layer, filtering out these damaging rays and maintaining a habitable environment for life on our planet.Oxidation also lies at the heart of the carbon cycle, a fundamental process that regulates the exchange of carbon between the Earth's various systems, including the atmosphere, biosphere, and lithosphere. Through the process of photosynthesis, plants absorb carbon dioxide from the air and, using the energy from the sun, convert it into organic compounds, releasing oxygen in the process. This oxygen is then utilized by living organisms, including humans, in the process of cellular respiration, where it is combined with glucose to produce energy. The carbon, in turn, is released back into the atmosphere as carbon dioxide, completing the cycle.The delicate balance of this cycle is crucial for maintaining the Earth's atmospheric composition and climate. Disruptions to the carbon cycle, often caused by human activities such as the burning of fossil fuels, can lead to an imbalance in the levels of greenhouse gases, contributing to climate change and its far-reaching consequences.Oxidation also plays a crucial role in the human body, where it is responsible for the generation of energy through the process of cellular respiration. In this process, oxygen is used to break down glucose and other organic compounds, releasing the energy stored within these molecules. This energy is then used to power the various functions of the body, from the beating of the heart to the firing of neurons in the brain.However, the process of oxidation can also have negative consequences for the human body. Excessive oxidation, known as oxidative stress, can lead to the formation of harmful free radicals, which can damage cells and contribute to the development of various diseases, including cancer, heart disease, and neurodegenerative disorders. To combat this, the body has developed a complex system of antioxidants, which work to neutralize these free radicals and maintain a healthy balance of oxidation within the cells.The importance of oxidation extends far beyond the realms ofindustry, the natural world, and human health. In the field of energy production, oxidation plays a crucial role in the generation of electricity and the powering of various technologies. The burning of fossil fuels, for example, is a process of oxidation that releases the energy stored within these compounds, which can then be harnessed to generate electricity and power our homes, businesses, and transportation systems.Similarly, the development of renewable energy sources, such as solar and wind power, also relies on the principles of oxidation. In the case of solar power, the interaction between photons of light and the electrons in solar cells leads to the generation of an electrical current, a process that is fundamentally driven by the principles of oxidation and reduction.As we look to the future, the understanding and management of oxidation will become increasingly crucial in addressing the pressing challenges facing our world. From the development of more efficient and sustainable energy sources to the design of materials that are resistant to corrosion, the ability to harness and control the power of oxidation will be key to ensuring a brighter and more sustainable future for all.In conclusion, the oxidation situation is a complex and multifaceted phenomenon that permeates every aspect of our lives, from thenatural world to the technological innovations that power our societies. By deepening our understanding of this fundamental chemical process, we can unlock new possibilities for addressing the challenges of our time and shaping a better tomorrow for generations to come.。

Although CNTs and their N-doped counterparts have been synthesized and studied for some years,the large-scale preparation of graphene sheets by chemical vapor deposition(CVD)is only the recent development.17,18More recently,attempts have been quartz purging min. furnaceFigure1.(a)A digital photo image of a transparent N-graphenefilmfloating on water after removal of the nickel layer by dissolving in an aqueous acid so-lution;(b,c)AFM images of the N-graphenefilm and the correpsonding height analyses along the lines marked in the AFM image(c1؊c3in panel c).Figure2.TEM and Raman analyses of the N-graphenefilms.(a)Low-magnification TEM image showing a few layers of the CVD-grown N-graphenefilm on a grid.Inset shows the correspondingelectron diffraction pattern.(b؊d)High magnification TEM imagesshowing edges of the N-graphenefilm regions consisting of(b)2,(c)4,and(d)ca.4؊8graphene layers.(e)The corresponding Ramanspectra of the N-graphenefilms of different graphene layers on aSiO2/Si substrate(Methods).XPS survey for the as-synthesized N-graphene shows the high-resolution N1s spectrum.the C-graphene suggests a stronger O2the former,an additional advantage asRRDE voltammograms for the ORR in air-saturated0.1M KOH at the C-graphene electrode(red line), line),and N-graphene electrode(blue line).Electrode rotating rate:1000rpm.Scan rate:0.01V/s.Mass Mass(N-grapene)؍7.5␮g.(b)Current density(j)؊time(t)chronoamperometric responses obtained at theN-graphene(square line)electrodes at؊0.4V in air saturated0.1M KOH.The arrow indicates the addition methanol into the air-saturated electrochemical cell.(c)Current(j)؊time(t)chronoamperometric response and N-graphene(square line)electrodes to CO.The arrow indicates the addition of10%(v/v)CO into KOH at؊0.4V;j o defines the initial current.(d)Cyclic voltammograms of N-graphene electrode inbefore(circle line)and after(square line)a continuous potentiodynamic swept for200000cycles at Scan rate:0.1V/s.。

钙钛矿催化剂英语Perovskite Catalysts: A Promising Pathway to a Sustainable FuturePerovskite materials have emerged as a remarkable class of catalysts, offering a versatile and efficient solution to a wide range of environmental and energy-related challenges. These materials, with their unique crystal structure and tunable properties, have captured the attention of researchers worldwide, paving the way for innovative applications in various fields including renewable energy, pollution control, and chemical synthesis.At the heart of perovskite catalysts lies their exceptional ability to facilitate critical chemical reactions. The perovskite structure, consisting of a central metal cation surrounded by an octahedron of anions, provides a highly customizable platform for tailoring catalytic performance. By substituting different elements into the perovskite lattice, researchers can fine-tune the material's electronic structure, surface properties, and catalytic activity, enabling targeted optimization for specific applications.One of the most promising applications of perovskite catalysts is in the realm of renewable energy. Perovskite materials havedemonstrated exceptional efficiency in the water-splitting reaction, a crucial process for the generation of clean hydrogen fuel. By leveraging the unique redox properties of perovskites, researchers have developed highly active and stable catalysts for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), the two half-reactions that comprise water splitting. These perovskite-based catalysts have shown superior performance compared to traditional precious metal-based catalysts, making them a cost-effective and sustainable alternative for large-scale hydrogen production.Moreover, perovskite catalysts have also found applications in the field of carbon dioxide (CO2) reduction, a vital process for mitigating greenhouse gas emissions and achieving a circular carbon economy. Perovskite-based electrocatalysts have demonstrated the ability to selectively convert CO2 into valuable chemicals and fuels, such as carbon monoxide, formic acid, and methanol, with high efficiency and selectivity. This capability holds immense promise for the development of integrated CO2 capture and utilization systems, contributing to a more sustainable and environmentally-friendly future.Beyond renewable energy applications, perovskite catalysts have also made significant strides in the field of pollution control. These materials have shown remarkable catalytic activity in the removal ofvarious air and water pollutants, including nitrogen oxides (NOx), sulfur oxides (SOx), volatile organic compounds (VOCs), and heavy metals. Perovskite-based catalysts can effectively oxidize or reduce these harmful substances, transforming them into less toxic or even benign compounds. This versatility makes perovskite catalysts a promising solution for addressing pressing environmental challenges, such as urban air pollution and water contamination.In the realm of chemical synthesis, perovskite catalysts have also showcased their potential. These materials have been employed in a wide range of organic transformations, including hydrogenation, oxidation, and coupling reactions. Perovskite catalysts have demonstrated superior activity, selectivity, and stability compared to traditional metal-based catalysts, opening up new avenues for the development of more efficient and sustainable chemical processes.The remarkable performance of perovskite catalysts can be attributed to their unique structural and electronic properties. The flexibility of the perovskite structure allows for the incorporation of a diverse range of elements, enabling the fine-tuning of catalytic activity and selectivity. Additionally, the strong metal-oxygen bonds in perovskites confer excellent thermal and chemical stability, crucial for maintaining catalytic performance under harsh reaction conditions.Furthermore, the scalable and cost-effective synthesis methods for perovskite materials have made them increasingly attractive for industrial applications. Compared to traditional precious metal-based catalysts, perovskite catalysts can be produced using more abundant and less expensive raw materials, making them a more economically viable option for large-scale deployment.As the field of perovskite catalysts continues to evolve, researchers are exploring innovative strategies to further enhance their performance and broaden their applications. This includes the development of nanostructured perovskite catalysts with increased surface area and active site density, the integration of perovskites with other functional materials to create hybrid catalytic systems, and the exploration of novel perovskite compositions for targeted catalytic reactions.In conclusion, perovskite catalysts have emerged as a transformative technology, offering a promising pathway towards a more sustainable future. Their versatility, efficiency, and cost-effectiveness have positioned them as a game-changing solution in renewable energy, pollution control, and chemical synthesis. As research and development in this field continue to advance, the impact of perovskite catalysts is poised to extend far beyond their current applications, contributing to a cleaner, more environmentally-friendly, and resource-efficient world.。

氟氮掺杂的有序介孔碳材料合成实验研究殷馨;刘嘉威;赵丹;周志明;杨泽仁;王海文【摘要】采用硬模板法,使用价格低廉的间苯二酚作为炭前驱体,采用氟化铵作为氟氮来源,合成氟氮掺杂的有序介孔碳(F-N-OMC).在1 000 ℃时制备的氟氮掺杂的有序介孔碳材料中,大量的氟氮原子(F原子数分数为0.35%,N为2.25%)均匀注入到高表面积的石墨化碳基体(671.3 cm2/g)和有序介孔通道内(6.2 nm).碳骨架内的氟氮原子的合成效果可以显著地极化相邻碳原子,并推动由缺陷引发的氧还原反应活性部位的形成.这将有助于氧还原反应性能的提高,因此氟氮掺杂的介孔碳材料有望成为高效的氧还原反应催化剂.%By adopting a hard template method,the ordered mesoporous Kong Tan (F-N-OMC) doped with fluorine nitrogen is synthesized by using inexpensive resorcinol as carbon precursor and ammonium fluoride as a fluorine and nitrogen source.Considerable fluorine and nitrogen atoms (F: 0.35 at%,N: 2.25 at%) are homogeneously implanted in the graphitic carbon matrix with high surface area (671.3cm2/g) and ordered mesoporous channels (6.2 nm) of FN-OMC prepared at the optimized heat-treatment temperature of 1 000 ℃.The synergistic effect of fluorine and nitrogen atoms in carbon frameworks is demonstrated to sharply polarize adjacent carbon atoms and promote the formation of the active sites of oxygen reduction reactions induced by defects.This will help to improve the performance of oxygen reduction reaction.Therefore,the FN-OMC is expected to become an efficient catalyst for oxygen reduction reaction.【期刊名称】《实验技术与管理》【年(卷),期】2017(034)007【总页数】6页(P49-54)【关键词】介孔碳;氟氮掺杂;非金属【作者】殷馨;刘嘉威;赵丹;周志明;杨泽仁;王海文【作者单位】华东理工大学化学与分子工程学院, 上海 200237;华东理工大学化学与分子工程学院, 上海 200237;华东理工大学化学与分子工程学院, 上海200237;华东理工大学化学与分子工程学院, 上海 200237;华东理工大学化学与分子工程学院, 上海 200237;华东理工大学化学与分子工程学院, 上海 200237【正文语种】中文【中图分类】O643.36动力学迟缓的氧还原反应已然成为阻碍金属空气电池和燃料电池发展的瓶颈[1-7]。