Synergistic Effect of Nickel Oxyhydroxide and Tungsten Carbide in Electrocatalytic Alcohol Oxidation

Abstract

Design and synthesis of efficient small organic molecule-based electrooxidation catalysts in replacing conventional oxygen evolution reaction (OER) catalysts has been considered as an alternative path to enable largescale renewable energy storage. In contrast to OER, alcohol oxidation reactions can be implemented at lower applied potentials along with generating higher value-added byproducts than oxygen. Here, the ultrafine Ni/WC hybrid nanoparticles (NPs) were successfully synthesized via an in situ trapping and space-confinement pyrolysis strategy. The as-synthesized Ni/WC hybrid NPs exhibit high electrooxidation performances in oxidizing methanol, ethanol, iso-propanol, ethylene glycol, and propylene glycol in alkaline solution. Particularly, for the methanol oxidation reaction, Ni/WC NPs demonstrate high reaction activity (specific activity: 325 mA cm −2 at 0.6 V vs Ag/AgCl/3.5 M KCl; mass activity: 1363 mA mg −1 ) and excellent stability (catalytic current drops ∼6.8% after 4 h). In the first 6 h of the electrolysis process, methanol was effectively converted into formate with ca. 93.8% Faraday efficiency. Based on in situ IR spectra and control catalyst experiments, tungsten carbide (WC) and nickel oxyhydroxide (NiOOH, derived from Ni) species are capable of activating different functional groups of methanol. More interestingly, their hybrid structure (Ni/WC) demonstrates improved catalytic performance in converting methanol into a formate product for the synergistic effect.

Effect of Silicon Carbide and Tungsten Carbide on Concrete Composite

“…The hybrid carbide WC and SiC showed high flexural strength. WC is usually mixed with other metals because of its capacity for synergistic effects [ 39 , 40 , 41 , 42 ]. Lin et al found a synergistic effect of WC and SiC on a composite [ 40 ].…”

Circumventing Challenges: Design of Anodic Electrocatalysts for Hybrid Water Electrolysis Systems

“…The electro‐oxidation of methanol with a simple structure attracts more attention compared with other compounds with longer chains. [ 31,42 ] However, six electrons are still involved in this oxidation reaction, imposing a complex mechanism with several reaction intermediates. Typically, a dual‐compete reaction mechanism is constituted by direct pathway and indirect pathway.…”

Cyanogel‐Induced PdCu Alloy with Pd‐Enriched Surface for Formic Acid Oxidation and Oxygen Reduction

“…[4][5][6][7][8] Palladium (Pd), as an alternative material of Pt, has been widely used in ORR because of its comparable performance [9][10][11] Moreover, the direct dehydrogenation pathway is more profitable on Pd than on Pt in FAOR, which is manifested by faster reaction kinetics, lower oxidation potential, better anti-CO poisoning, and higher selectivity catalytic activity. [12][13][14] In spite of that, Pd has still suffered from difficulty in electrocatalytic property and soaring prices. [15] Alloying Pd with cheap transition metals (Co, Fe, Ni, and Cu) is an effective strategy to increase its catalytic performance and utilization efficiency.…”