Li Huanhuan, Huang Can, Li Yingying, Yang Weijun, Liu Fan
College of Chemistry and Chemical Engineering, Hunan University Changsha 410082 China
RSC Adv. 2019 Jul 22;9(39):22523-22530. doi: 10.1039/c9ra02932j. eCollection 2019 Jul 17.
A core-shell structure electrocatalyst for trace nitrobenzene reduction was prepared with Mn(ii)[5,10,15,20-tetra(4-aminophenyl)porphyrin] (MnTAPP) and graphene oxide (GO) as raw materials. Firstly, MnTAPP and GO were combined together by covalent bonds, and then the supported MnTAPP was coupled together through -dibromobenzene, a conjugated bridging agent, to obtain a more stable graphene-oxide@polymerized-manganese-porphyrin composite (GMPP@AMP). The structure and morphology of the GMPP@AMP were characterized by FT-IR, Raman spectroscopy, SEM and TEM. The GMPP@AMP modified glassy carbon electrode (GMPP@AMP/GCE) was prepared and the electrochemical activity of GMPP@AMP towards nitrobenzene reduction was evaluated by cyclic voltammetry (CV). The results showed that GMPP@AMP/GCE had a more positive reduction potential than MnTAPP/GCE and GO/GCE, and the reduction current responded more sensitively. Electrocatalytic reduction currents of nitrobenzene were found to be linearly related to concentration over the range 0.04 to 0.24 mM using a differential pulse voltammogram (DPV) method. Nitrobenzene is easily compatible with polymerized MnTAPP which has rich nitrogen-containing functional groups and porous structure, and the highly conductive GO combined with the polymerized MnTAPP having excellent electron transfer ability. This produced a significant synergistic catalytic effect during the electrocatalytic reaction of trace nitrobenzene. The novel composite has good application prospects in electrochemical detection of trace nitrobenzene compounds in the environment.
以Mn(ii)5,10,15,20-四(4-氨基苯基)卟啉和氧化石墨烯(GO)为原料制备了一种用于痕量硝基苯还原的核壳结构电催化剂。首先，通过共价键将MnTAPP和GO结合在一起，然后通过共轭桥联剂对二溴苯将负载的MnTAPP偶联在一起，得到更稳定的氧化石墨烯@聚合锰卟啉复合材料(GMPP@AMP)。采用傅里叶变换红外光谱(FT-IR)、拉曼光谱、扫描电子显微镜(SEM)和透射电子显微镜(TEM)对GMPP@AMP的结构和形貌进行了表征。制备了GMPP@AMP修饰玻碳电极(GMPP@AMP/GCE)，并通过循环伏安法(CV)评价了GMPP@AMP对硝基苯还原的电化学活性。结果表明，GMPP@AMP/GCE比MnTAPP/GCE和GO/GCE具有更正的还原电位，还原电流响应更灵敏。采用差分脉冲伏安法(DPV)发现，硝基苯的电催化还原电流在0.04~0.24 mM范围内与浓度呈线性关系。硝基苯易于与具有丰富含氮官能团和多孔结构的聚合MnTAPP相容，高导电性的GO与具有优异电子转移能力的聚合MnTAPP相结合。这在痕量硝基苯的电催化反应过程中产生了显著的协同催化效应。该新型复合材料在环境中痕量硝基苯化合物的电化学检测方面具有良好的应用前景。
