A direct H2O2 production based on hollow porous carbon sphere-sulfur nanocrystal composites by confinement effect as oxygen reduction electrocatalysts  

作　　者：Guanyu Chen Jiwei Liu Qingqing Li Pengfei Guan Xuefeng Yu Linshen Xing Jie Zhang Renchao Che 

机构地区：[1]Laboratory of Advanced Materials,Department of Materials Science and Collaborative Innovation Center of Chemistry for Energy Materials(iChem),Fudan University,Shanghai 200438,China [2]Beijing Computational Science Research Center,Beijing 100193,China [3]Innovative Center for Advanced Materials(ICAM),Hangzhou Dianzi University,Hangzhou 310012,China

出　　处：《Nano Research》2019年第10期2614-2622,共9页纳米研究（英文版）

基　　金：This work was supported by the Ministry of Science and Technology of China(No.2018YFA0209102);the National Natural Science Foundation of China(Nos.11727807,51725101,51672050 and 61790581);the Science and Technology Commission of Shanghai Municipality(No.l6DZ2260600).

摘　　要：Carbon-sulfur composites have draw n in creasing interest in various fields including electrocatalysis because of their unique structures.However,carb on-sulfur composite with tiny sulfur nano crystals has still received little attention.Herein,hollow porous carb on sphere-sulfur composite(HPCS-S)which possesses excellent electrochemical performance towards H2O2 has been prepared for the first time via a simple silica template method.The 2-5 nm sulfur nan ocrystals being restricted in the cha nnel of the hollow porous carb on spheres are un der a strong compressive stress,which was further con firmed by high-resoluti on tran smissi on electr on microscopy(HRTEM)and GPA.The HPCS-S nano crystals show better con ductivity tha n amorphous sulfur clusters because of the reducti on of the steric hindrance which efficie ntly promotes the electron transportation.Consequently,the higher activity and selectivity towards the 2e^oxygen reduction reaction(ORR)to H2O2 in alkaline solution was obtained.The H2O2 selectivity rises from 20%to over 70%after the sulfur addition and the H2O2 production rate achieves 183.99 mmol-gcataiyst-1 with the Faradaic efficiency of 70%.Furthermore,performance enhancement mechanism was also investigated using the den sity functional theory(DFT)calculatio ns.After the in troduci ng of sulfur nano crystals,the appeara nee of S-S bond greatly decreases the overpotential compared with S-doping,which results in significant enhancement of the electrocatalytic property.Consequently,the HPCS-S can be an efficient H2O2 production electrocatalyst in alkaline solution.

关 键 词：SULFUR nanocrystal hydrogen PEROXIDE PRODUCTION carbon SPHERE oxygen reduction reaction 

分 类 号：TB3[一般工业技术—材料科学与工程]