Steps towards highly-efficient water splitting and oxygen reduction using nanostructured β-Ni(OH)2. Issue 16 (30th March 2022)

• Record Type: Journal Article
• Authors: Balčiūnaitė, Aldona; Upadhyay, Kush K.; Radinović, Kristina; Santos, Diogo M. F.; Montemor, M. F.; Šljukić, Biljana
• Is Part Of: RSC advances. Volume 12:Issue 16(2022)
• Page Start: 10020
• Page End: 10028
• Publication Date: 2022-03-30
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d2ra00914e
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : β-Ni(OH)2 nanoplatelets produced via a hydrothermal method exhibit good performance as trifunctional electrocatalysts for the ORR, OER, and HER in alkaline media along with excellent stability under cathodic/anodic polarisation conditions. Abstract : β-Ni(OH)2 nanoplatelets are prepared by a hydrothermal procedure and characterized by scanning and transmission electron microscopy, X-ray diffraction analysis, Raman spectroscopy, and X-ray photoelectron spectroscopy. The material is demonstrated to be an efficient electrocatalyst for oxygen reduction, oxygen evolution, and hydrogen evolution reactions in alkaline media. β-Ni(OH)2 shows an overpotential of 498 mV to reach 10 mA cm −2 towards oxygen evolution, with a Tafel slope of 149 mV dec −1 (decreasing to 99 mV dec −1 at 75 °C), along with superior stability as evidenced by chronoamperometric measurements. Similarly, a low overpotential of −333 mV to reach 10 mA cm −2 (decreasing to only −65 mV at 75 °C) toward hydrogen evolution with a Tafel slope of −230 mV dec −1 is observed. Finally, β-Ni(OH)2 exhibits a noteworthy performance for the ORR, as evidenced by a low Tafel slope of −78 mV dec −1 and a number of exchanged electrons of 4.01 (indicating direct 4e − -oxygen reduction), whereas there are only a few previous reports on modest ORR activity of pure Ni(OH)2 .