title: Nanocrystal Engineering of Sputter-Grown CuO Photocathode for Visible-Light-Driven Electrochemical Water Splitting.
abstract: Cupric oxide (CuO) thin film was sputtered onto fluorine-doped tin oxide (FTO) coated glass substrate and incorporated into a photoelectrochemical (PEC) cell as a photocathode. Through in situ nanocrystal engineering, sputtered CuO film shows an improvement in its stability and photocurrent generation capability. For the same CuO film thickness (150 nm), films deposited at a sputtering power of 300 W exhibit a photocurrent of ∼0.92 mAcm(-2) (0 V vs RHE), which is significantly higher than those deposited at 30 W (∼0.58 mAcm(-2)). By increasing the film thickness to 500 nm, the photocurrent is further enhanced to 2.5 mAcm(-2), which represents a photocurrent conversion efficiency of 3.1%. Systematic characterization using Raman, XRD, and HR-TEM reveals that the high sputtering power results in an improvement in CuO film crystallinity, which enhances its charge transport property and, hence, its photocurrent generation capabilities.
authors.affiliation: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way; Innovis, #08-03, Singapore 138634.
authors.forename: Saeid
authors.initials: S
authors.lastname: Masudy-Panah
authors.affiliation: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way; Innovis, #08-03, Singapore 138634.
authors.forename: Roozbeh
authors.initials: R
authors.lastname: Siavash Moakhar
authors.affiliation: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way; Innovis, #08-03, Singapore 138634.
authors.forename: Chin Sheng
authors.initials: CS
authors.lastname: Chua
authors.affiliation: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way; Innovis, #08-03, Singapore 138634.
authors.forename: Hui Ru
authors.initials: HR
authors.lastname: Tan
authors.affiliation: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way; Innovis, #08-03, Singapore 138634.
authors.forename: Ten It
authors.initials: TI
authors.lastname: Wong
authors.affiliation: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way; Innovis, #08-03, Singapore 138634.
authors.forename: Dongzhi
authors.initials: D
authors.lastname: Chi
authors.affiliation: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way; Innovis, #08-03, Singapore 138634.
authors.forename: Goutam Kumar
authors.initials: GK
authors.lastname: Dalapati
keywords: CuO photocathode; nanocrystal engineering; stability; water splitting