Amino functionalized carbon nanotubes supported CoNi@CoO–NiO core/shell nanoparticles as highly efficient bifunctional catalyst for rechargeable Zn-air batteries. (1st January 2021)

• Record Type: Journal Article
• Authors: Pan, Hongzhou; Cao, Yuwei; Zhang, Baoan; Han, Jiaqi; Bai, Yunfei; Shang, Xiaonan; Jiang, Zhongqing; Tian, Xiaoning; Jiang, Zhong-Jie
• Is Part Of: International journal of hydrogen energy. Volume 46:Number 1(2021)
• Page Start: 374
• Page End: 388
• Publication Date: 2021-01-01
• Subjects: CoNi alloy -- Core-shell nanoparticles -- Amino functionalized carbon nanotubes -- Bifunctional catalyst -- Zinc-air battery; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2020.09.174
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are the core reaction processes of rechargeable Zn-air battery (ZAB) cathode. Therefore, exploring a bifunctional catalyst with excellent electrochemical performance, high durability, and low cost is essential for rechargeable ZAB. In this work, amino functionalized carbon nanotubes supported core/shell nanoparticles composed of CoNi alloy core and CoO–NiO shell (CoNi@CoO–NiO/NH2 -CNTs-1) is synthesized through a simple and efficient hydrothermal reaction and calcination method, which shows higher ORR/OER bifunctional catalytic performance than the single metal-based catalyst, such as Ni@NiO/NH2 -CNTs and Co@CoO/NH2 -CNTs. The fabricated bimetallic alloy based catalyst CoNi@CoO–NiO/NH2 -CNTs-3 with the optimized loading content of CoNi@CoO–NiO core/shell nanoparticles, presents the best bifunctional catalytic performance for ORR/OER. Experimental studies reveal that CoNi@CoO–NiO/NH2 -CNTs-3 exhibits the onset potential of 0.956 V and 1.423 V vs. RHE for ORR and OER, respectively. It also exhibits a low overpotential of 377 mV to achieve a 10 mA cm −2 current density for OER, and positive half-wave potentials of 0.794 V for ORR. And the potential difference between half-wave potential of ORR (E1/2 ) and the potential at 10 mA cm −2 for OER (Ej10 ) is 0.813 V. In addition, when CoNi@CoO–NiO/NH2 -CNTs-3 is used as an air electrode catalyst of rechargeable ZAB, its maximum power density and open circuit voltage (OCV) can reach 128.7 mW cm −2 and 1.458 V (The commercially available catalyst of Pt/C–RuO2 is 88.1 mW cm −2 ), which strongly demonstrates that the fabricated catalyst CoNi@CoO–NiO/NH2 -CNTs-3 can be used as a highly efficient bifunctional catalyst for ZABs, and is expected to replace those expensive precious metal electrocatalysts to meet the growing demand for new energy devices. Graphical abstract: Amino functionalized carbon nanotubes supported core-shell nanoparticles composed of CoNi alloy core and CoO–NiO shell (CoNi@CoO–NiO/NH2 -CNTs) is successfully prepared by a simple, green and sustainable method for application in rechargeable Zn-air batteries. Image 1 Highlights: NH2 -CNTs supported core/shell CoNi@CoO–NiO nanoparticles is synthesized. It shows higher ORR/OER catalytic performance than the single metal-based catalyst. The CoNi@CoO–NiO/NH2 -CNTs-3 presents optimal bifunctional catalytic performance. The maximum power density of the assembled ZAB can reach 128.7 mW cm −2 .