Hierarchical CoWO 4 /Ni x Fe y S microspheres bearing crystalline-amorphous interface as a multifunctional platform for outperformed water splitting and sensitive hydrazine sensing

• Published in: Journal of colloid and interface science 2024-06, Vol.664, p.756
• Main Authors: Qian, Qi, Chen, Chenxin, Zheng, Xuan, Wang, Qingxiang, Gao, Feng, Zou, Zehua
• Format: Article
• Language: English
• ISSN: 1095-7103
• DOI: 10.1016/j.jcis.2024.03.052

Highly efficient and multifunctional electrocatalysts are of high value in energy transformation and electrochemical sensing. Herein, hierarchically architectured cobalt tungstate/nickel iron sulfide (CoWO /Ni Fe S) microspheres with a crystalline-amorphous interface have been prepared on bimetallic substrate of nickel-iron foam (NIF) by a two-step hydrothermal method. Electrochemical characterization shows that CoWO /Ni Fe S microspheres can boost the electrocatalytic activity effectively through the synergistic effect on the crystalline-amorphous interface. When the CoWO /Ni Fe S is applied as the electrocatalysts for oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), the overpotentials at a high current density of 500 mA cm are only 322.8 mV and 306.5 mV, respectively. The overall water splitting device composed of CoWO /Ni Fe S/NIF couple only needs a cell voltage of 1.80 V to reach a current density of 100 mA cm , and 2.19 V to reach 500 mA cm . The CoWO /Ni Fe S/NIF can be also utilized as an effective electrochemical platform for the sensing of toxic hydrazine in a wide range from 50 μM to 17.3 mM, with a detection limit of 46.4 μM. All these results display that the CoWO /Ni Fe S/NIF can be a high-performance multifunctional material for energy transformation and environmental pollutant monitoring.