侧链含吡啶聚三噻吩/rGO/Pd复合材料的制备及甲醇电催化氧化性能

Preparation and Methanol Electrooxidation Performance of Pendant Pyridinyl Grafted Polyterthiophene/rGO/Pd Composites

以D-A结构的3-吡啶基-2,5-二噻基噻吩为单体,调节单体与还原氧化石墨烯的配比,通过原位溶液聚合修饰还原氧化石墨烯(rGO),制备了催化剂载体polymer/rGO_(80%)和polymer/rGO_(50%)复合物。然后将Pd纳米粒子负载到rGO,polymer/rGO_(80%)和polymer/rGO_(50%)上,制备了rGO/Pd,polymer/rGO_(80%)/Pd和polymer/rGO_(50%)/Pd电催化剂。通过红外光谱、扫描电镜、透射电镜及电感耦合等离子体发射光谱对电催化剂进行表征,并采用循环伏安和计时电流等电化学测试方法对电催化剂的甲醇电催化氧化性能进行了研究。结果表明,rGO/Pd,polymer/rGO_(80%)/Pd和polymer/rGO_(50%)/Pd在0.5 mol/L KOH溶液中的电化学活性表面积分别为195.2 cm^(2)/mg,280.1 cm^(2)/mg和428.1 cm^(2)/mg;rGO/Pd,polymer/rGO_(80%)/Pd和polymer/rGO_(50%)/Pd在0.5 mol/L KOH+1 mol/L CH3OH体系中甲醇电催化氧化峰电流密度分别为235.31 mA/mg,783.83 mA/mg和1146.36 mA/mg,与rGO/Pd相比,polymer/rGO_(80%)/Pd和polymer/rGO_(50%)/Pd的电催化活性分别为rGO/Pd的3.3倍和4.9倍,表明聚合物在复合物中的最佳质量分数为50%。侧链含吡啶聚三噻吩修饰rGO,可以增强rGO/Pd电催化剂的电催化性能和电催化稳定性。

Polymer/rGO_(80%)and polymer/rGO_(50%)as supporting materials of electrocatalyst were prepared by modification of reduced graphene oxide(rGO)via in-situ polymerization of 3-pyridinyl-2,5-dithienylthiophene with D-A structure as monomer through adjusting the ratio of monomer and rGO.Then,rGO/Pd,polymer/rGO_(80%)/Pd and polymer/rGO_(50%)/Pd composites were prepared by loading platinum nano-particle on surface of rGO,polymer/rGO_(80%)and polymer/rGO_(50%).The electrocatalys were characterized by Fourier translation infrared spectroscopy(FT-IR),scanning electron microscope(SEM),transmission electron microscope(TEM)and inductively coupled plasma atomic emission spectrometry(ICP-AES).Methanol electrooxidation performance of electrocatalys was studied by these electrochemical test methods such as cyclic voltammetry measurement and amperometric I-t curve measurement.The results show that electrochemically active surface area of rGO/Pd,polymer/rGO_(80%)/Pd and polymer/rGO_(50%)/Pd in 0.5 mol/L KOH solution is 195.2 cm^(2)/mg,280.1 cm^(2)/mg and 428.1 cm^(2)/mg,respectively.The methanol electrooxidation peak current densities of rGO/Pd,polymer/rGO_(80%)/Pd and polymer/rGO_(50%)/Pd in 0.5 mol/L KOH+1 mol/L CH3OH solution are 235.31 mA/mg,783.83 mA/mg and 1146.36 mA/mg,respectively.Comparing with rGO/Pd,the electrocatalytic activities of polymer/rGO_(80%)/Pd and polymer/rGO_(50%)/Pd are 3.3 times and 4.9 times that of rGO/Pd,respectively.These results indicate that the optimum amount of polymer in composite is 50%.The rGO modified with pendant pyridinyl grafted polyterthiophene can enhance the electrocatalytic performance and electrocatalytic stability of rGO/Pd electrocatalyst.