物理化学学报2022，Vol.38Issue(7)：56-65,10.DOI:10.3866/PKU.WHXB202111021
空心NiCo2S4纳米球助催化剂担载Znln2S4纳米片用于可见光催化制氢
Hollow NiCo2S4 Nanospheres as a Cocatalyst to Support Znln2S4 Nanosheets for Visible-Light-Driven Hydrogen Production
摘要
Abstract
The rational interface tailoring of nanosheets on hollow spheres is a promising strategy to develop efficient photocatalysts for hydrogen production with solar energy.Among the various photocatalyst materials,metal sulfides have been extensively researched because of their relatively narrow band gap and superior visible-light response.Znln2S4 is a layered ternary chalcogenide semiconductor photocatalyst with a tunable band gap energy(approximately 2.4 eV).Among various metal sulfide photocatalysts,Znln2S4 has gained considerable attention.However,intrinsic Znln2S4 only exhibits a relatively moderate photocatalytic activity,which is mainly owing to the high recombination and low migration rate of photocarriers.Loading cocatalysts onto semiconductor photocatalysts is an effective way to improve the performance of photocatalysts,because it can not only facilitate the separation of electron-hole pairs,but also reduce the activation energy for proton reduction.As a ternary transition metal sulfide,NiCo2S4 features a high electrical conductivity,low electronegativity,excellent redox properties,and outstanding electrocatalytic activity.Such favorable characteristics suggest that NiCo2S4 can expedite charge separation and transfer,thereby promoting photocatalytic H2 production by serving as a cocatalyst.Moreover,both NiCo2S4 and Znln2S4 possess the ternary spinel crystal structure,which may facilitate the construction of NiCo2S4/Znln2S4 hybrids with tight interfacial contact for an enhanced photocatalytic performance.Herein,ultrathin Znln2S4 nanosheets were grown in situ on a non-noble-metal cocatalyst,namely NiCo2S4 hollow spheres,to form hierarchical NiCo2S4@Znln2S4 hollow heterostructured photocatalysts with an intimately coupled interface and strong visible light absorption extending to ca.583 nm.The optimized NiCo2S4@Znln2S4 hybrid with a NiCo2S4 content of ca.3.1％exhibited a high hydrogen evolution rate of 78 μmol·h-1,which was approximately 9 times higher than that of bare Znln2S4 and 3 times higher than that of 1％(w,mass fraction)Pt/Znln2S4.Additionally,the hybrid photocatalysts displayed good stability in the reaction.Photoluminescence and electrochemical analysis results indicated that NiCo2S4 hollow spheres served as an efficient cocatalyst for facilitating the separation and transport of light-induced charge carriers as well as reducing the hydrogen evolution reaction barrier.Finally,a possible reaction mechanism for the photocatalytic hydrogen evolution was proposed.In the NiCo2S4@Znln2S4 composite photocatalyst,the NiCo2S4 cocatalyst with high electrical conductivity favorably accepts the photoinduced electrons transferred from Znln2S4 and then employs the electrons to reduce protons for H2 production on the reactive sites.Concurrently,the photogenerated holes are trapped by TEOA that acts as a hole scavenger to accomplish the photoredox cycle.This study provides guidance for the fabrication of hierarchical hollow heterostructures based on nanosheet semiconductor subunits as remarkable photocatalysts for hydrogen production.关键词
光催化/产氢/助催化剂/金属硫化物Key words
Photocatalysis/H2 production/Cocatalyst/Metal sulfides分类
化学化工引用本文复制引用
熊壮,侯乙东,员汝胜,丁正新,王伟俊,汪思波..空心NiCo2S4纳米球助催化剂担载Znln2S4纳米片用于可见光催化制氢[J].物理化学学报,2022,38(7):56-65,10.基金项目
This work was supported financially by the National Key R&D Program of China(2021YFA1502100),the National Science Foundation of China(U1805255)and the State Key Laboratory of NBC Protection for Civilian(SKLNBC2020-18).国家重点研发计划(2021YFA1502100),国家自然科学基金(U1805255),国民核生化灾害防护国家重点实验室开放基金(SKLNBC2020-18)资助项目 （2021YFA1502100）
