Self-motivated,thermally oxidized hematite nanoflake photoanodes:Effects of pre-polishing and ZrO_(2) passivation layer  

作　　者：Love Kumar Dhandole Hyun Hwi Lee Weon-Sik Chae Jum Suk Jang Jae Sung Lee 

机构地区：[1]Department of Energy Engineering,School of Energy and Chemical Engineering,Ulsan National Institute of Science and Technology(UNIST),Ulsan 44919,Republic of Korea [2]Division of Biotechnology,College of Environmental and Bioresource Sciences,Chonbuk National University,Iksan 54596,Republic of Korea [3]Pohang Accelerator Laboratory,Pohang University of Science and Technology(POSTECH),Pohang 37673,Republic of Korea [4]Daegu Center,Korea Basic Science Institute,Daegu 41566,Republic of Korea

出　　处：《Journal of Energy Chemistry》2022年第2期415-423,共9页能源化学（英文版）

基　　金：supported by the Climate Change Response Project(NRF-2019M1A2A2065612);the Basic Science Grant(NRF2019R1A4A1029237);Korea-China Key Joint Research Program(2017K2A9A2A11070341)funded by the Ministry of Science and ICT;the 2019 Research Fund(1.190013.01)of UNIST;support by the Basic Science Research Programs through the National Public Technology Program based on Environmental Policy(2014000160001);the SRC program through the National Research Foundation of Korea(NRF2015R1A5A1009962)。

摘　　要：High-temperature thermal oxidation of an Fe foil produces a high-quality,crystalline hematite nanoflake suitable as a photoanode for the photoelectrochemical(PEC)water oxidation.Physical pre-polishing of the foil surface has a profound effect in the formation of a vertically-aligned nanoflakes of hematite phase with extended(110)planes by removing the loosely-bonded oxide layer.When the surface of the photoanode is modified with a ZrO_(2) passivation layer and a cobalt phosphate co-catalyst,the charge recombination at the photoanode-electrolyte interface is greatly suppressed to improve its overall PEC activity.As a result,the photocurrent density at 1.10 VRHE under 1 sun condition is enhanced from 0.22 mA cm^(-2) for an unmodified photoanode to 0.59 mA cm^(-2) for the fully modified photoanode,and the photocurrent onset potential is shifted cathodically by 400 mV.Moreover,the photoanode demonstrates outstanding stability by showing steady production of H_(2) and O_(2) gases in the stoichiometric ratio of 2:1 in a continuous PEC operation for 10 h.

关 键 词：Fe foil Thermal oxidation NANOFLAKES Photoelectrochemical water splitting Surface modifications 

分 类 号：TQ116.2[化学工程—无机化工] TB383.1[一般工业技术—材料科学与工程]