A High-Efficiency Hematite Photoanode with Enhanced Bonding Energy Around Fe Atoms

Lan, Yangchun2; Kang, Shuai3; Cui, Dehu2; Hu, Zhuofeng1

2021-02-24

10.1002/chem.202004569

CHEMISTRY-A EUROPEAN JOURNAL   影响因子和分区

0947-6539

1521-3765

Hematite nanoarrays are important photoanode materials. However, they suffer from serious problems of charge transfer and surface states; in particular, the surface states hinder the increase in photocurrent. A previous strategy to suppress the surface state is the deposition of an Fe-free metal oxide overlayer. Herein, from the viewpoint of atomic bonding energy, it is found that the strength of bonding around Fe atoms in the hematite is the key to suppressing the surface states. By treating the surface of hematite with Se and NaBH4, the Fe2O3 transforms to a double-layer nanostructure. In the outer layer, the Fe-O bonding is reinforced and the Fe-Se bonding is even stronger. Therefore, the surface states are inhibited and the increase in the photocurrent density becomes much faster. Besides, the treatment constructs a nanoscale p-n junction to promote the charge transfer. Improvements are achieved in onset potential (0.25 V shift) and in photocurrent density (5.8 times). This work pinpoints the key to suppressing the surface states and preparing a high-efficiency hematite nanoarray, and deepens our understanding of hematite photoanodes.

bonding energy electrochemistry hematite photoelectrochemistry surface state

SCI ; EI

英语

第一 ; 通讯

National Natural Science Foundation of China[51902357] ; Natural Science Foundation of Guangdong Province, China[2019A1515012143] ; Start-up Funds for High-Level Talents of Sun Yat-sen University[38000-18841209] ; Fundamental Research Funds for the Central Universities[19lgpy153] ; Guangdong Basic and Applied Basic Research Foundation[2019B1515120058] ; 5G Frontier Project of Nanshan, Shenzhen[K20799112]

Chemistry

Chemistry, Multidisciplinary

WOS:000612637400001

WILEY-V C H VERLAG GMBH

20210509839957

Atoms ; Charge transfer ; Metals ; Photocurrents ; Sodium Borohydride ; Surface states

Minerals:482.2 ; Electricity: Basic Concepts and Phenomena:701.1 ; Chemical Reactions:802.2 ; Classical Physics; Quantum Theory; Relativity:931 ; Atomic and Molecular Physics:931.3 ; High Energy Physics; Nuclear Physics; Plasma Physics:932

CHEMISTRY

Web of Science

1.Sun Yat Sen Univ, Sch Environm Sci & Engn, Guangdong Prov Key Lab Environm Pollut Control &, Guangzhou 510275, Peoples R China
2.Southern Univ Sci & Technol, Sch Microelect, Shenzhen 518055, Peoples R China
3.Chinese Acad Sci, Micronano Mfg & Syst Integrat Ctr, Chongqing Inst Green & Intelligent Technol CIGIT, Chongqing 400714, Peoples R China

Lan, Yangchun,Kang, Shuai,Cui, Dehu,et al. A High-Efficiency Hematite Photoanode with Enhanced Bonding Energy Around Fe Atoms[J]. CHEMISTRY-A EUROPEAN JOURNAL,2021,27(12):4089-4097.

Lan, Yangchun,Kang, Shuai,Cui, Dehu,&Hu, Zhuofeng.(2021).A High-Efficiency Hematite Photoanode with Enhanced Bonding Energy Around Fe Atoms.CHEMISTRY-A EUROPEAN JOURNAL,27(12),4089-4097.

Lan, Yangchun,et al."A High-Efficiency Hematite Photoanode with Enhanced Bonding Energy Around Fe Atoms".CHEMISTRY-A EUROPEAN JOURNAL 27.12(2021):4089-4097.