Fe/Ni Bimetallic Organic Framework Deposited on TiO₂ Nanotube Array for Enhancing Higher and Stable Photoelectrochemical Activity of Oxygen Evaluation Reaction

• 出版年: Nanomaterials
• 主要な著者: Sheng-Mu You, Waleed M. A. El Rouby, Annadurai Thamilselvan, Cheng-Kuo Tsai, Win Darmanto, Ruey-An Doong, Pierre Millet
• フォーマット: 論文
• 言語: 英語
• 出版事項: MDPI AG 2020-08-01
• 主題: titanium dioxide nanotube array (TNTA); bimetallic organic framework; water oxidation; oxygen evolution reaction (OER); photoelectrocatalyst
• オンライン･アクセス: https://www.mdpi.com/2079-4991/10/9/1688

Photoelectrochemical (PEC) water splitting is a promising strategy to improve the efficiency of oxygen evolution reactions (OERs). However, the efficient adsorption of visible light as well as long-term stability of light-harvesting electrocatalysis is the crucial issue in PEC cells. Metal–organic framework (MOF)-derived bimetallic electrocatalysis with its superior performance has wide application prospects in OER and PEC applications. Herein, we have fabricated a nickel and iron bimetallic organic framework (FeNi-MOF) deposited on top of anodized TiO₂ nanotube arrays (TNTA) for PEC and OER applications. The FeNi-MOF/TNTA was incorporated through the electrochemical deposition of Ni²⁺ and Fe³⁺ onto the surface of TNTA and then connected with organic ligands by the hydrothermal transformation. Therefore, FeNi-MOF/TNTA demonstrates abundant photoelectrocatalytic active sites that can enhance the photocurrent up to 1.91 mA/cm² under 100 mW/cm² and a negligible loss in activity after 180 min of photoreaction. The FeNi-MOF-doped photoanode shows predominant photoelectrochemical performance due to the boosted excellent light-harvesting ability, rapid photoresponse, and stimulated interfacial energy of charge separation under the UV-visible light irradiation conditions. The results of this study give deep insight into MOF-derived bimetallic nanomaterial synthesis for photoelectrochemical OER and provide guidance on future electrocatalysis design.