Anodic Porous NiO Film Formation for the Hexavalent Chromium Removal under Ultraviolet Irradiation

• Published in: Journal of Physics: Conference Series
• Main Author: Rosli S.A.; Alias N.; Misran H.; Matsuda A.; Tan W.K.; Kawamura G.; Razak K.A.; Lockman Z.
• Format: Conference paper
• Language: English
• Published: Institute of Physics 2024
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85215125251&doi=10.1088%2f1742-6596%2f2907%2f1%2f012025&partnerID=40&md5=33de871ecb294384d9399524a38f2267

Anodic porous nickel oxide (NiO) was grown by anodization of Ni in ethylene glycol (EG) added to NH4F at 60 V in a two-step anodic process. The first process produced hydrated anodic film which was removed before the foil was subjected to a second anodic process. This led to the formation of porous structure with pore diameters of a 90 -180 nm. Formation of porous structure was done as to provide a larger specific surface area that can increase the removal efficiency of the hexavalent chromium. The as-anodized anodic film was then annealed at 300 qC to improve the adhesion of nickel oxides porous to substrates before being used as a photocatalyst to reduce Cr(VI) in a synthetic wastewater under ultraviolet (UV) irradiation. Porous NiO showed a good photocatalyst performance in reducing Cr(VI) to Cr(III) with 60% reduction after 150 min. However, with the addition of ethylenediaminetetraacetic acid (EDTA), 100% reduction was achieved after 120 min indicating that EDTA is required as holes scavengers. © 2024 Institute of Physics Publishing. All rights reserved.