Conjugated pi Electrons of MOFs Drive Charge Separation at Heterostructures Interface for Enhanced Photoelectrochemical Water Oxidation

···材料科学与工程学院-中文···

论文题目:Conjugated pi Electrons of MOFs Drive Charge Separation at Heterostructures Interface for Enhanced Photoelectrochemical Water Oxidation

论文作者:Xuewei Wang, Wenming Sun, Yang Tian, Kun Dang, Qimeng Zhang, Zhurui Shen*, Sihui Zhan*

发表期刊:Small, 17(14), 2100367, 2021    

Abstract: 

Photoanode material with high efficiency and stability is extensively  desirable in photoelectrochemical (PEC) water splitting for  green/renewable energy source. Herein, novel heterostructures is  constructed via coating rutile TiO2 nanorods with metal organic  framework (MOF) materials UiO-66 or UiO-67 (UiO-66@TiO2 and  UiO-67@TiO2), respectively. The pi electrons in the MOF linkers could  increase the local electronegativity near the heterojunction interface  due to the conjugation effect, thereby enhancing the internal electric  field (IEF) at the heterojunction interface. The IEF could drive charge  transfer following Z-scheme mechanism in the prepared heterostructures,  inducing photogenerated charge separation efficiency increasing as 156%  and 253% for the UiO-66@TiO2 and UiO-67@TiO2, respectively.  Correspondingly, the UiO-66@TiO2 and UiO-67@TiO2 enhanced the  photocurrent density as approximate two- and threefolds compared with  that of pristine TiO2 for PEC water oxidation in universal pH  electrolytes. This work demonstrates an effective method of regulating  the IEF of heterojunction toward further improved charge separation.