Liquid-Phase Deposition Synthesis of ZIF-67-Derived Synthesis of Co₃O₄@TiO₂ Composite for Efficient Electrochemical Water Splitting

• Main Authors: Zaffar Ahmed Shaikh, Asif Ali Laghari, Oleg Litvishko, Valery Litvishko, Tatyana Kalmykova, Artur Meynkhard
• Format: Article
• Language: English
• Published: MDPI AG 2021-03-01
• Series: Metals
• Subjects: water splitting; HER; OER; Co₃O₄@TiO₂ composite; current density; the onset potential
• Online Access: https://www.mdpi.com/2075-4701/11/3/420

In this article, a novel Co₃O₄@TiO₂ composite is synthesized by applying two-step methods. ZIF-67 is synthesized and used as a template for the synthesis of the composite. The composite is designed by using the effective photocatalytic properties of Co₃O₄ and TiO₂. The resulting synthesized composite is supposed to offer superior properties compared to their counterparts. The synthesized Co₃O₄@TiO₂ composite is characterized by powder X-ray diffraction (PXRD), Brunauer–Emmet–Teller (BET), atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Electrochemical water splitting, including hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) studies on the Co₃O₄@TiO₂ composite, is evaluated by cyclic voltammetry (CV) and linear sweep voltammetry (LSV) analysis in a 2M aqueous KOH electrolyte. The current generation stability of these samples is deliberated by chronoamperometric measurements. It is observed, from LSV results at a 1 mV/s scan rate, that metal oxides incorporated on other metal oxides have a higher current density and lower onset potential as compared to pure metal oxides. From the obtained results, it has become evident that synthesized studies on the Co₃O₄@TiO₂ composite possess significant potential for electrochemical water splitting with the lowest onset potential, highest current density, better OER, and HER activity.