Laser Deposited Nanostructured Thin Film Catalyst of Cobalt Oxide for Hydrogen Generation

¹Laser & Plasma Surface Processing Section, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India

²Department of Physics, University of Mumbai, Vidyanagari, Santacruz (East), Mumbai 400098, India

³Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India

Adv. Mater. Lett., 2021, 12 (1), 21011594

DOI: 10.5185/amlett.2021.011594

Publication Date (Web): Dec 09, 2020

Copyright © IAAM-VBRI Press

E-mail: jadhav.hs2013@gmail.com

Abstract

Thin film with immobilized particulates of Cobalt oxide (Co₃O₄) has been synthesized by Pulsed Laser Deposition (PLD) technique followed by thermal treatment in air. Surface morphology of the Co₃O₄ films was examined using Field Emission Scanning Electron Microscopy (FESEM). Crystalline structure of Co₃O₄ films was investigated by X-ray Diffraction (XRD) and Raman spectroscopy was used to confirm the presence of Co₃O₄ phase on the surface. Efficient catalytic performance was obtained with these films for hydrolysis in Sodium Borohydride (NaBH₄). A maximum hydrogen generation rate of ~5100 mL min^-1 g^-1 of catalyst was recorded at a temperature of 305 K with calculated activation energy of 62.96 kJ/mol. Good catalytic activity could be attributed to nanostructures of the films formed following heat treatment consisting of densely packed nanoparticles (NPs) which act as active catalytic centers, and the immobilized nature of the particles on the surface of the films. These catalyst films showed no major loss of activity even after five cycles of use allowing at the same time an advantage of easy separation from the solution. Our results thus demonstrate good catalytic performance and reusability of such PLD deposited Co₃O₄ nanostructured films towards hydrogen production by hydrolysis of NaBH₄.

Keywords

Immobilized nanostructures, hydrogen production, pulsed laser deposition