Assembly of Al-oxo porphyrin frameworks on Si nanowire for enhanced photoelectrocatalytic hydrogen evolution  

铝氧卟啉促进Si纳米线光电催化分解水产氢性能

作　　者：WANG Ke-ke YUAN Xiu-hong LI Wen-zhang 王可可;袁秀洪;李文章(School of Chemistry and Chemical Engineering,Hunan University of Science and Technology,Xiangtan 411201,China;Department of Clinical Psychology,the Third Xiangya Hospital of Central South University,Changsha 410083,China;School of Chemistry and Chemical Engineering,Central South University,Changsha 410083,China)

机构地区：[1]School of Chemistry and Chemical Engineering,Hunan University of Science and Technology,Xiangtan 411201,China [2]Department of Clinical Psychology,the Third Xiangya Hospital of Central South University,Changsha 410083,China [3]School of Chemistry and Chemical Engineering,Central South University,Changsha 410083,China

出　　处：《Journal of Central South University》2024年第12期4560-4571,共12页中南大学学报(英文版)

基　　金：Project(22078368)supported by the National Natural Science Foundation of China。

摘　　要：The utilization of solar energy for hydrogen production via water splitting has garnered considerable attention in the realm of renewable energy.Si nanowires photocathodes own the advantages of effective photon absorption,non toxicity and industrial applicability.Nevertheless,the photoelectrocatalytic(PEC)performance of Si nanowires photocathodes is still limited by ineffective or deficient active sites on their surfaces.Here,we develop an efficient Si based photocathode modified with Al-porphyrin-based MOF(Al-PMOF),consisted of an earth-abundant metal containing Al(OH)O_(4) cluster bridged by 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin.The assembled Al-PMOF significantly enhances the photocurrent density of bare Si nanowires photocathodes,resulting in a twofold increase under equivalent conditions,alongside a positive shift of 200 mV in the onset potential of the Si/Al-PMOF photocathode.The improved PEC hydrogen evolution performance is ascribed to accelerate surface charge transfer of Si photocathode and provision of favorable active site for the hydrogen evolution reaction.This work provides insights into the fabrication of semiconductor/molecule catalyst hybrid photocathodes,thus facilitating the realization of high-efficiency PEC water splitting.利用太阳能光电催化分解水产氢在可再生能源领域引起了广泛关注。硅(Si)纳米线光阴极具有宽的光吸收范围、无毒和工业适用性的优点。然而,Si纳米线光阴极表面缺乏有效析氢活性位点,限制了其光电催化分解水性能。本文以含铝金属Al(OH)O_(4)簇通过5,10,15,20-四(4-羧基苯基)卟啉桥接方式,设计制备了铝卟啉基金属有机框架结构(Al-PMOF),并将其修饰于Si纳米线光阴极上,研究了Al-PMOF对Si纳米线光电催化分解水性能的影响。结果表明,Al-PMOF显著提高了Si纳米线光阴极的光电催化性能,与Si纳米线相比,相同条件下光电流密度提升了两倍。同时,Si/Al-PMOF光阴极的起始电势正向移动了200 mV。电化学阻抗谱(EIS)和调制光电流谱(IMPS)测试表明,Al-PMOF加速了Si光阴极的表面电荷转移,并提供了有效的析氢反应活性位点。研究成果有望为高效光电催化分解水制氢光阴极的设计及制备提供了借鉴。

关 键 词：photoelectrocatalytic water splitting Si photocathode Al-PMOF hydrogen evolution reaction charge transfer 

分 类 号：TQ116.2[化学工程—无机化工] O643.36[理学—物理化学] TB383.1[理学—化学]