Oxygen Vacancies Dominated NiS₂/CoS₂ Interface Porous Nanowires for Portable Zn–Air Batteries Driven Water Splitting Devices

Abstract

The development of highly active and stable oxygen evolution reaction (OER) electrocatalysts is crucial for improving the efficiency of water splitting and metal-air battery devices. Herein, an efficient strategy is demonstrated for making the oxygen vacancies dominated cobalt-nickel sulfide interface porous nanowires (NiS /CoS -O NWs) for boosting OER catalysis through in situ electrochemical reaction of NiS /CoS interface NWs. Because of the abundant oxygen vacancies and interface porous nanowires structure, they can catalyze the OER efficiently with a low overpotential of 235 mV at j = 10 mA cm and remarkable long-term stability in 1.0 m KOH. The home-made rechargeable portable Zn-air batteries by using NiS /CoS -O NWs as the air-cathode display a very high open-circuit voltage of 1.49 V, which can maintain for more than 30 h. Most importantly, a highly efficient self-driven water splitting device is designed with NiS /CoS -O NWs as both anode and cathode, powered by two-series-connected NiS /CoS -O NWs-based portable Zn-air batteries. The present work opens a new way for designing oxygen vacancies dominated interface nanowires as highly efficient multifunctional electrocatalysts for electrochemical reactions and renewable energy devices.

Bimetallic NiMoN Nanowires with a Preferential Reactive Facet: An Ultraefficient Bifunctional Electrocatalyst for Overall Water Splitting

“…[35,36] The catalytic ability of electrocatalysts varies with the particle size and morphology. [38][39][40] In accordance with the Brewer hypo-hyper-d-electronic theorya nd the volcano plot of electrocatalytic activity, [41,42] we Faceted nanomaterials with highly reactive exposed facets have been the target of intense researches owing to their significantly enhanced catalytic performance. [38][39][40] In accordance with the Brewer hypo-hyper-d-electronic theorya nd the volcano plot of electrocatalytic activity, [41,42] we Faceted nanomaterials with highly reactive exposed facets have been the target of intense researches owing to their significantly enhanced catalytic performance.…”

CuCo2S4 Nanosheets@N‐Doped Carbon Nanofibers by Sulfurization at Room Temperature as Bifunctional Electrocatalysts in Flexible Quasi‐Solid‐State Zn–Air Batteries

“…[28][29][30] In addition, to properly make use of the intrinsic advantage of BSs, a novel fabrication approach is to directly grow the electrically conductive BSs on N-doped carbon materials (BSs@NMSs), which would ensure with a better contact with the conductive matrix. This will be in contrast to those processes completed at high hydrothermal temperatures [28,29,31,32] or chemical vapor deposition (CVD; they are usually higher than 600 °C), [33,34] which are tedious and time consuming. This will be in contrast to those processes completed at high hydrothermal temperatures [28,29,31,32] or chemical vapor deposition (CVD; they are usually higher than 600 °C), [33,34] which are tedious and time consuming.…”

“…[31] In particular, it would be further desirable to develop the sulfide phase at a low temperature, ideally at room temperature. Most importantly, the mechanical strength of BSs@NCMs-based electrodes is heat sensitive and easily damaged to lose flexibility in these processes, [31,32] thus also hinder its large-scale application of flexible ZABs in portable and wearable electronic devices. Most importantly, the mechanical strength of BSs@NCMs-based electrodes is heat sensitive and easily damaged to lose flexibility in these processes, [31,32] thus also hinder its large-scale application of flexible ZABs in portable and wearable electronic devices.…”

Plasma‐Triggered Synergy of Exfoliation, Phase Transformation, and Surface Engineering in Cobalt Diselenide for Enhanced Water Oxidation

“…[7] Selective control of the crystal structure is another effective way. [13] Despite so much progress in separately regulating these factors (exfoliation, phase transformation, and surface engineering) for better catalytic activity,there have not been reports on efficient integration of them in one material system, which is believed to allow the optimal chemical and electronic structure toward the OER to be achieved.Herein, we report the successful integration of exfoliation, cubic-to-orthorhombic phase transformation, and surface oxidative reorganization in cobalt diselenide (CoSe 2 )through aconvenient Ar/O 2 plasma method (Scheme 1). [9] Although cubic-to-orthorhombic (c-to-o) transition has been described through at hermal method [10] and the reverse change theoretically can be realized by rotating half of the X 2 2À groups, [11] there is still lack of facile means to actually establish this conversion from pyrites to marcasites at present.…”

“…[9] Although cubic-to-orthorhombic (c-to-o) transition has been described through at hermal method [10] and the reverse change theoretically can be realized by rotating half of the X 2 2À groups, [11] there is still lack of facile means to actually establish this conversion from pyrites to marcasites at present. [13] Despite so much progress in separately regulating these factors (exfoliation, phase transformation, and surface engineering) for better catalytic activity,there have not been reports on efficient integration of them in one material system, which is believed to allow the optimal chemical and electronic structure toward the OER to be achieved. [12] Early studies have revealed that the formation of ah eterojunction metal dichalcogenide/oxide interface can significantly improve the relevant OER energetics,yet precise controllability is hard to realize.…”