Boosting Electrocatalytic Oxygen Evolution over Ce−Co₉S₈ Core–Shell Nanoneedle Arrays by Electronic and Architectural Dual Engineering

Abstract

An dual electronic and architectural engineering strategy is a good way to rationally design earth-abundant and highly efficient electrocatalysts of the oxygen evolution reaction (OER) for sustainable hydrogen-based energy devices. Here, a Ce-doped Co 9 S 8 core-shell nanoneedle array (CeÀ Co 9 S 8 @CC) supported on a carbon cloth has been designed and developed to accelerate the sluggish kinetics of the OER. Profiting from valance alternative Ce doping, a fine core-shell structure and vertically aligned nanoneedle arrayed architecture, CeÀ Co 9 S 8 @CC integrates modulated electronic structure, highly exposed active sites, and multidimensional mass diffusion channels; together, these afford a favorable catalyzed OER. CeÀ Co 9 S 8 @CC exhibits remarkable performance in the OER in an alkaline medium, where the overpotential requires only 242 mV to deliver a current density of 10 mA cm À 2 for the OER; this is 70 mV superior to that of Cefree Co 9 S 8 catalyst and other counterparts. Good stability and impressive selectivity (nearly 100 % Faradic efficiency) are also demonstrated. When integrated into a two-electrode OER// HER electrolyzer, the as-prepared CeÀ Co 9 S 8 @CC displays a low operation potential of 1.54 V at 10 mA cm À 2 and long-term stability, thus demonstrating great potential for economical water electrolysis.

Electrochemical Performance Evaluation of Bimetallic Sulfide Nanocomposite with Fullerene (CeNdS/C60) for Efficient Oxygen Evolution Reaction (OER)

“…On the other hand, modified Nd-doped CeS electrodes also increased the appropriate active sites to drive OER, but their poor electrical conductivity , and steep decreased anodic peak current impede the good OER performance. Therefore, CeS, Nd-doped CeS electrocatalysts displayed a large decrease in activity by observing higher overpotentials of 385 and 372 mV (vs RHE) for the same current density that slowed the charge-transport processes in OER.…”

Al-Incorporated Cobalt-Layered Double Hydroxides for Enhanced Oxygen Evolution through Morphology and Electronic Structure Regulation

“…This is because, under current reaction conditions, the [Al(OH) 4 ] − can be easily obtained rather than Al(OH) 3 , which is due to the high stability constants of [Al(OH) 4 ] − . 20 Because of its stability in an alkaline environment, AlF 3 is much easier to form in the presence of F − than Al(OH) 3 . In such a case, substantially more Al 3+ is deposited on the CC substrate as opposed to growing there.…”

“…Developing efficient technologies for hydrogen (H 2 ) generation is of paramount importance to solving the environmental pollution and energy crisis caused by fossil energy and has become a vital research hotspot. , Electrochemical water splitting using high-efficiency catalysts shows great advantages in realizing industry-scale H 2 production. However, the oxidative half-reaction of the oxygen evolution reaction (OER) is seriously depressed by the high energy barrier and sluggish kinetics caused by the intricate four-electron pathway, which is considered the rate-determining step for water splitting . RuO 2 and IrO 2 are high-powered electrocatalysts for OER, but their widespread applications always suffer from high prices and resource scarcity .…”

“…However, the oxidative half-reaction of the oxygen evolution reaction (OER) is seriously depressed by the high energy barrier and sluggish kinetics caused by the intricate four-electron pathway, which is considered the rate-determining step for water splitting. 3 RuO 2 and IrO 2 are high-powered electrocatalysts for OER, but their widespread applications always suffer from high prices and resource scarcity. 4 Hence, the development of alternative electrocatalysts with low cost and high activity has attracted major concerns.…”

Porous Ni3S2–Co9S8 Carbon Aerogels Derived from Carrageenan/NiCo-MOF Hydrogels as an Efficient Electrocatalyst for Oxygen Evolution in Rechargeable Zn–Air Batteries

“…Huang et al studied that N, O, and S three-layer carbon-coated Co 9 S 8 materials exhibited significant catalytic performance of OER . Although transition metal sulfides have achieved the above significant achievements, their electrocatalytic activity is still unsatisfactory due to their inherent poor electrical conductivity, and further improvement is needed. − Therefore, anchoring or embedding highly active cobalt sulfide nanoparticles and interfacial synergism of different metal sulfide nanoparticles on heteroatom-doped carbon materials is a promising approach to solve this issue . Previously, due to the synergistic effect of the NiCoDH/NiCoS interface, the electrocatalytic efficiency of OER was improved by NiCo sulfide nanosheets (NiCoDH/NiCoS) modified with NiCo hydroxide nanodots .…”