多孔气凝胶Co_(9)S_(8)的结构调控与光电催化性能研究  

Structural Regulation of Porous Aerogel Co_(9)S_(8) for Boosting Photoelectronic Catalytic Performance

作　　者：王涛[1] 廖鑫元 贺世杰 黄智 林华[1,2] WANG Tao;LIAO Xinyuan;HE Shijie;HUANG Zhi;LIN Hua(School of Materials and Energy,Southwest University,Chongqing 400715,China;Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies,Chongqing 400715,China)

机构地区：[1]西南大学材料与能源学院,重庆400715 [2]重庆洁净能源与先进材料重点实验室,重庆400715

出　　处：《西南大学学报（自然科学版）》2022年第4期187-195,共9页Journal of Southwest University(Natural Science Edition)

基　　金：国家自然科学基金项目(52072310);重庆市自然科学基金项目(cstc2019jcyj-msxmX0206).

摘　　要：增大比表面积、增加反应活性位点是提升过渡金属硫化物催化性能的重要途径.本文采用溶胶—凝胶法与低温处理成功制备了结构合理的Co_(9)S_(8)多孔气凝胶(CSA),其比表面积和孔隙率是传统方法制备Co_(9)S_(8)纳米片(CSS)的4倍以上.析氧反应(OER)研究表明,CSA在10 mA/cm^(2)电流密度下的过电位为331 mV,Tafel斜率仅为75 mV/dec,而相同条件下CSS分别为400 mV和82 mV/dec;在光催化性能测试中,CSA在80 min可降解亚甲基蓝(MB)达98%以上,并保持较高的循环稳定性.机理分析发现,CSA由于气凝胶结构具有大的比表面积,在OER过程中能够快速地进行表面重构,形成更多的催化反应活性位点,发达的孔结构能加快物质/电荷的转移与传输,也有利于产生更多的电子空穴对促进光催化反应.Increasing specific surface area and active sites is an important way to improve the catalytic performance of transition metal sulfide.In this paper,Co_(9)S_(8)(CSA)aerogel has been prepared through sol-gel method,of which specific surface area and pore volume are more than four times of those of Co_(9)S_(8)(CSS)prepared by hydrothermal method.Electrocatalytic oxygen evolution reaction(OER)studies showed that the overpotential of CSA at the current density of 10 mA/cm^(2) was 331 mV,with a very low Tafel slope of 75 mV/dec,while the CSS was 400 mV and 82 mV/dec,respectively.Photocatalytic degradation experiments showed that CSA requires only 60 min to degrade more than 90%of methylene blue(MB),and its degradation rate is three times than that of CSS.Mechanism analysis shows that CSA can rapidly carry out surface reconstruction in the OER process due to the large specific surface area of the aerogel structure,and form more catalytic reaction active sites.The developed pore structure can accelerate the transfer and transmission of matter/charge,and also facilitate the generation of more electron hole pairs to promote the photocatalytic reaction.

关 键 词：气凝胶 Co_(9)S_(8) 双功能催化剂 析氧反应 光催化 

分 类 号：TB321[一般工业技术—材料科学与工程]