Active Edge Site Exposed β‐Ni(OH)₂ Nanosheets on Stainless Steel Mesh as a Versatile Electrocatalyst for the Oxidation of Urea, Hydrazine, and Water

Abstract

Energy generation through electrochemical conversion while addressing the environmental concerns has always been the topic of interest to the scientific community. Particularly, the development of low‐cost and efficient electrocatalyst gained attention for large‐scale energy and clean‐energy production. But now the emphasis is on developing low‐cost and efficient electrocatalyst materials that show more than one electrocatalytic reactions. Hence, we have developed a highly porous and active edge plane exposed β‐Ni(OH)2 nanosheet on low‐cost and flexible stainless‐steel mesh (SSM) and investigated its catalytic activity for oxidation of urea, hydrazine, and water. The as‐prepared β‐Ni(OH)2/SSM demonstrates the excellent catalytic activity towards the urea oxidation reaction (UOR), hydrazine oxidation reaction (HzOR), and oxygen evolution reaction (OER) with potential lower than the 1.45 V vs. RHE, 1.34 V vs. RHE, and 1.51 V vs. RHE at 50 mA/cm2 current density, respectively. Furthermore, the as‐prepared electrocatalyst demonstrates excellent stability in UOR, HzOR, and OER for long time. The promising electrocatalytic activity of as‐prepared β‐Ni(OH)2/SSM electrocatalyst is attributed to the highly porous, and edge plane exposed binder‐free thin nanosheets grown on SSM, which also adds to the mechanical structure stability and a large amount of mass transportation during electrocatalytic activity.

A facile chemical synthesis of nanoflake NiS2layers and their photocatalytic activity

“…00-011-0099), 45 with no additional peaks related to any other crystalline nickel compounds such as nickel oxide, nickel hydroxide and other phases of nickel sulfides, indicating the complete transformation of the Ni(OH) 2 phase to NiS 2 phase. 47–49 The XRD analysis well matched with reported studies in literature. 28,30,31,50 The average crystallite size ( D ) of the NiS 2 layer was calculated using the Scherrer–Debye formula (eqn (6)) for the (200) reflection plane.where K is the Debye constant, λ is the X-ray wavelength, β is the line broadening at full width at half maximum of the diffraction peak, and θ is the Bragg's angle.…”

Coupling of Thermal and Electrochemical-Activated Stainless-Steel Mesh as a Highly Robust Electrocatalyst for Oxygen Evolution Reaction

“…Therefore, one of the best ways to overcome the abovementioned problems is to directly modify the conducting substrate to enhance OER performance. To do so, the strategy of creating freestanding electrodes on conducting substrates is an elixir on the method of nonfreestanding electrodes. , The beauty of freestanding electrodes is the controlled three-dimensional (3D) porous electrocatalyst material with different morphology networks on the substrate by controlling the experimental parameters or varying the synthesis method. The freestanding 3D porous catalyst on conducting substrates does not only improve the conductivity of the catalyst but also increases the number of active sites.…”

Waste is the best: end-of-life lithium ion battery-derived ultra-active Ni3+-enriched β-Ni(OH)2 for the electrocatalytic oxygen evolution reaction

“…The presence of both Ni 2+ and Ni 3+ in β-Ni(OH) 2 implies the presence of considerable defects and vacancies in the structure due to the partial replacement of bivalent Ni (Ni 2+ ) by trivalent Ni (Ni 3+ ). 22,38 The high-resolution O 1s XPS spectrum could be resolved into four signals corresponding to NiO*OH (O 1 , 529.1 eV), Ni–O (O 2 , 530.68 eV), hydroxyl moieties (O 3 , 531.14 eV) and adsorbed water molecules (O 4 , 532.8 eV) respectively (Fig. 2d).…”