Cu doped NiO thin film photocathodes for enhanced PEC performance

• Published in: Superlattices and microstructures Vol. 159; p. 107050
• Main Authors: Sahoo, Pooja, Sharma, Akash, Padhan, Subash, Thangavel, R.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2021
• Subjects: Cu doped NiO; Photocurrent density; Sol-gel processes; Water splitting; Sol-gel processes; Water splitting; Photocurrent density; Cu doped NiO
• ISSN: 0749-6036; 1096-3677
• DOI: 10.1016/j.spmi.2021.107050

The present report describes the fabrication of undoped NiO and Cu doped NiO based photocathodes synthesized by sol gel spin coating technique. Mott-Schottky, LSV and EIS measurements have been carried out to investigate the PEC properties of these photocathodes. 3% Cu doped NiO film exhibits the highest PEC performance among all photocathodes. The p-type semiconducting nature of all thin film samples has been confirmed from the M-S plots. Also, the values of carrier density have been tuned from 1.18 × 1020 to 1.36 × 1020 cm−3 for undoped NiO and 3% Cu doped NiO thin films. VB CB levels of the as-prepared photocathodes have been calculated from absorption spectra. 3Cu:NiO exhibits a significantly higher photocurrent density of −6.97 mA/cm2 at −1.5 V vs. Ag/AgCl in 0.1M NaOH solution under UV illumination. The superior PEC performance is due to efficient charge transport and reduced recombination rate of the photogenerated electron-hole pairs. These findings demonstrate the potential of Cu doped NiO photocathodes in water splitting applications. [Display omitted] •NiO and Cu doped NiO thi films fabrication was carried out via sol-gel, spin coating technique.•3Cu:NiO exhibited the highest photocurrent denisty of -6.97 mA/cm2 at -1.5V vs Ag/AgCl under UV light.•Carrier density of 1.36 x 1020 cm-3 was estimated for 3Cu:NiO from Mott-Schottky Analysis.