Thermally constructed stable Zn-doped NiCoOx-z alloy structures on stainless steel mesh for efficient hydrogen production via overall hydrazine splitting in alkaline electrolyte

Anil Ashok Kashale; Akash Sanjay Rasal; Fei-Chien Hsu; ChangChun Chen; Sayali Nitin Kulkarni; Chun Hao Chang; Jia-Yaw Chang; Yuekun Lai; I-Wen Peter Chen

doi:10.1016/j.jcis.2023.02.142

Thermally constructed stable Zn-doped NiCoO_x-z alloy structures on stainless steel mesh for efficient hydrogen production via overall hydrazine splitting in alkaline electrolyte

J Colloid Interface Sci. 2023 Jun 15:640:737-749. doi: 10.1016/j.jcis.2023.02.142. Epub 2023 Mar 5.

Authors

Anil Ashok Kashale¹, Akash Sanjay Rasal², Fei-Chien Hsu³, ChangChun Chen⁴, Sayali Nitin Kulkarni⁵, Chun Hao Chang⁶, Jia-Yaw Chang⁷, Yuekun Lai⁸, I-Wen Peter Chen⁹

Affiliations

¹ Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan. Electronic address: kashale1987@gmail.com.
² Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan. Electronic address: akashrasal079@gmail.com.
³ Department of Applied Science, National Taitung University, 369, Sec. 2, University Rd., Taitung City, 95092, Taiwan. Electronic address: jing.cherry1018@gmail.com.
⁴ Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan. Electronic address: l36115029@gs.ncku.edu.tw.
⁵ Venture Center Pune, NCL Innovation Park, Dr. Homi Bhabha Rd, Pune, Maharashtra, 411008, India. Electronic address: sayalikulkarni567@gmail.com.
⁶ Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan. Electronic address: pqrs0511@gmail.com.
⁷ Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan. Electronic address: jychang@mail.ntust.edu.tw.
⁸ National Engineering Research Center of Chemical Fertilizer Catalyst (NERC-CFC), College of Chemical Engineering, Fuzhou University, Fuzhou, 350116, PR China. Electronic address: yklai@fzu.edu.cn.
⁹ Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan. Electronic address: iwchen1978@gs.ncku.edu.tw.

PMID: 36898180
DOI: 10.1016/j.jcis.2023.02.142

Abstract

Hydrogen has a high energy density of approximately 120 to 140 MJ kg^-1, which is very high compared to other natural energy sources. However, hydrogen generation through electrocatalytic water splitting is a high electricity consumption process due to the sluggish oxygen evolution reaction (OER). As a result, hydrogen generation through hydrazine-assisted water electrolysis has recently been intensively investigated. The hydrazine electrolysis process requires a low potential compared to the water electrolysis process. Despite this, the utilization of direct hydrazine fuel cells (DHFCs) as portable or vehicle power sources necessitates the development of inexpensive and effective anodic hydrazine oxidation catalysts. Here, we prepared oxygen-deficient zinc-doped nickel cobalt oxide (Zn-NiCoO_x-z) alloy nanoarrays on stainless steel mesh (SSM) using a hydrothermal synthesis method followed by thermal treatment. Furthermore, the prepared thin films were used as electrocatalysts, and the OER and hydrazine oxidation reaction (HzOR) activities were investigated in three- and two-electrode systems. In a three-electrode system, Zn-NiCoO_x-z/SSM HzOR requires -0.116 V (vs RHE) potential to achieve a 50 mA cm^-2 current density, which is dramatically lower than the OER potential (1.493 V vs RHE). In a two-electrode system (Zn-NiCoO_x-z/SSM(-)∥Zn-NiCoO_x-z/SSM(+)), the overall hydrazine splitting potential (OHzS) required to reach 50 mA cm^-2 is only 0.700 V, which is dramatically less than the required potential for overall water splitting (OWS). These excellent HzOR results are due to the binder-free oxygen-deficient Zn-NiCoO_x-z/SSM alloy nanoarray, which provides a large number of active sites and improves the wettability of catalysts after Zn doping.

Keywords: Hydrazine Oxidation Reaction; Hydrogen Evolution Reaction; Oxygen Evolution Reaction; Oxygen-Deficient Materials; Zinc Doping.