Intrinsic and extrinsic doping to construct hematite nanorod p-n homojunctions for highly efficient PEC water splitting

Wang，Haipeng1; Hu，Yan ling2; Song，Guang Ling1,3,4,5; Zheng，Da Jiang1

2022-05-01

10.1016/j.cej.2022.135016

CHEMICAL ENGINEERING JOURNAL   影响因子和分区

1385-8947

1873-3212

Hematite (α-FeO) as a promising photoanode material for photoelectrochemical (PEC) water splitting has some intrinsic shortcomings, such as low carrier concentration, fast electron-hole pair recombination, and thus poor PEC performance in practice. Herein, we fabricated p-n homojunctions on the α-FeO by introducing both intrinsic (oxygen vacancies, Vo) and extrinsic (Cu) dopants into the hematite lattice through a two-step hydrothermal process followed by an annealing treatment. Such α-FeO composite film photoanodes were characterized by surface analysis and photoelectrochemical test, and exhibited great PEC photolytic water properties. The Ultraviolet–visible (UV–vis) absorption results showed that the light absorption of the α-FeO with p-n homojunctions was greatly enhanced in the visible region. The introduction of intrinsic (Vo) and extrinsic (Cu) dopants into the α-FeO lattice enhanced the concentration of carriers by nearly two orders of magnitude, and the formation of the p-n homojunctions also effectively improved the separation efficiency of electron-hole pairs. The water oxidation photocurrent density of the α-FeO with the p-n homojunctions was measured to be 2.49 mA cm at 1.23 V (vs. RHE), nearly two orders of magnitude higher than that of the pristine α-FeO, and the reaction onset potential negatively shifted by more than 700 mV. Amazingly, the high potential photocurrent density at 1.6 V (vs. RHE) reached 4.79 mA cm, which is a high value very competitive among all the reported hematite photoanodes under the same conditions. Moreover, the high photocurrent density could retain 87% even after 3 h, indicating that the α-FeO p-n homojunction photoanode has also stable photo-electrochemical performance.

Extrinsic doping Hematite Intrinsic doping Oxygen evolution reaction P-n homojunction PEC water splitting

SCI ; EI

英语

其他

National Science of China[51731008,51671163]

Engineering

Engineering, Environmental ; Engineering, Chemical

WOS:000774906600001

ELSEVIER SCIENCE SA

20220611611048

Composite films ; Hole concentration ; Light absorption ; Nanorods ; Photocurrents ; Photoelectrochemical cells ; Semiconductor doping ; Surface analysis

Minerals:482.2 ; Electricity: Basic Concepts and Phenomena:701.1 ; Electric Batteries:702.1 ; Semiconducting Materials:712.1 ; Light/Optics:741.1 ; Nanotechnology:761 ; Solid State Physics:933 ; Materials Science:951

ENGINEERING

2-s2.0-85124186651

Scopus

1.Center for Marine Materials Corrosion and Protection,College of Materials,Xiamen University,Xiamen,422 S. Siming Rd, Fujian,361005,China
2.Fujian Provincial Key Laboratory of Functional Materials and Applications,School of Materials Science and Engineering,Xiamen University of Technology,Xiamen,361024,China
3.State Key Laboratory of Physical Chemistry of Solid Surfaces,Xiamen University,Xiamen,422 S. Siming Rd, Fujian,361005,China
4.Department of Ocean Science and Engineering,Southern University of Science and Technology,Shenzhen,Guangdong,518055,China
5.School of Engineering,the University of Queensland,St.Lucia,4068,Australia

Wang，Haipeng,Hu，Yan ling,Song，Guang Ling,et al. Intrinsic and extrinsic doping to construct hematite nanorod p-n homojunctions for highly efficient PEC water splitting[J]. CHEMICAL ENGINEERING JOURNAL,2022,435.

Wang，Haipeng,Hu，Yan ling,Song，Guang Ling,&Zheng，Da Jiang.(2022).Intrinsic and extrinsic doping to construct hematite nanorod p-n homojunctions for highly efficient PEC water splitting.CHEMICAL ENGINEERING JOURNAL,435.

Wang，Haipeng,et al."Intrinsic and extrinsic doping to construct hematite nanorod p-n homojunctions for highly efficient PEC water splitting".CHEMICAL ENGINEERING JOURNAL 435(2022).