Criss-crossed α-Fe2O3 nanorods/Bi2S3 heterojunction for enhanced photoelectrochemical water splitting. (15th September 2022)

• Record Type: Journal Article
• Authors: Tezcan, Fatih; Ahmad, Abrar; Yerlikaya, Gurbet; Zia-ur-Rehman, ; Paksoy, Halime; Kardas, Gülfeza
• Is Part Of: Fuel. Volume 324:Part A(2022)
• Publication Date: 2022-09-15
• Subjects: Hematite -- α-Fe2O3 -- Bi2S3 -- Heterojunction -- Hydrogen production -- PECs; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2022.124477
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: α-Fe2 O3 /Bi2 S3 have been successfully fabricated on FTO substrate by applying hydrothermal, SILAR and solvothermal approaches. SILAR approach is also applied before the solvothermal step to obtain a uniform heterojunction. α-Fe2 O3 /Bi2 S3 photoanode performs almost 20 times higher than pristine α-Fe2 O3 . Applied biased photon-to-current conversion efficiency shows improved light-harvesting efficiency of α-Fe2 O3 /Bi2 S3. Abstract: In this research work, α-Fe2 O3 /Bi2 S3 heterojunction photoelectrodes for improved photoelectrochemical water splitting have been successfully fabricated on FTO substrate by applying hydrothermal and solvothermal approaches. A seed layer approach is also applied before the solvothermal step for the homogeneous distribution of Bi2 S3 over α-Fe2 O3 nanorods to obtain a uniform heterojunction. The physicochemical and optical techniques results of α-Fe2 O3 /Bi2 S3 indicate high crystallinity, presence of two distant phases with different bandgap positions. Linear sweep voltammetry (LSV) results indicate that the optimized α-Fe2 O3 /Bi2 S3 photoanode performs a maximum photocurrent density of 2.550 mA cm −2 at 1.23 VRHE which is almost 20 times higher than pristine α-Fe2 O3 (0.123 mA cm −2 at 1.23 V RHE ). Electrochemical Impedance Spectroscopy (EIS) entirely shows α-Fe2 O3 /Bi2 S3 .6 h is the lowest Rp (180.9 Ω cm 2 ) compare to pristine Fe2 O3 (5810 Ω cm 2 ), indicating enhanced photocatalytic performance on OER and S 2 - / S 2 2 - cycle followed under 100 mW cm −2 solar irradiation. This significant upsurge in the photocurrent density and applied biased photon-to-current conversion efficiency shown by the heterojunction is attributed to the improved light-harvesting efficiency, enhanced conductivity, and effective charge separation at the α-Fe2 O3 /Bi2 S3 interface.