We present a straightforward method for one-pot electrodeposition of platinum atoms-doped molybdenum oxide (Pt·MoO3−x) films and show their superior electrocatalytic activity in the hydrogen evolution reaction (HER). A ~15-nm-thick Pt·MoO3−x film was prepared by one-pot electrodeposition at −0.8 V for 1 ms. Due to considerably different solute concentrations, the content of Pt atoms in the electrodeposited composite electrocatalyst is low. No Pt crystals or islands were observed on the flat Pt·MoO3−x films, indicating that Pt atoms were homogeneously dispersed within the MoO3−x thin film. The catalytic performance and physicochemical features of Pt·MoO3−x as a HER electrocatalyst were characterized. The results showed that our Pt·MoO3−x film exhibits 23- and 11-times higher current density than Pt and MoO3−x electrodeposited individually under the same conditions, respectively. It was found that the dramatic enhancement in the HER performance was principally due to the abundant oxygen defects. The use of the developed one-pot electrodeposition and doping method can potentially be extended to various catalytically active metal oxides or hydroxides for enhanced performance in various energy storage and conversion applications. 相似文献
High gravimetric energy density, earth-abundance, and environmental friendliness of hydrogen sources have inspired the utilization of hydrogen fuel as a clean alternative to fossil fuels. Hydrogen evolution reaction (HER), a half reaction of water splitting, is crucial to the low-cost production of pure H2 fuels but necessitates the use of electrocatalysts to expedite reaction kinetics. Owing to the availability of low-cost oxygen evolution reaction (OER) catalysts for the counter electrode in alkaline media and the lack of low-cost OER catalysts in acidic media, researchers have focused on developing HER catalysts in alkaline media with high activity and stability. Nickel is well-known as an HER catalyst and continuous efforts have been undertaken to improve Ni-based catalysts as alkaline electrolyzers. In this review, we summarize earlier studies of HER activity and mechanism on Ni surfaces, along with recent progress in the optimization of the Ni-based catalysts using various modern techniques. Recently developed Ni-based HER catalysts are categorized according to their chemical nature, and the advantages as well as limitations of each category are discussed. Among all Ni-based catalysts, Ni-based alloys and Ni-based hetero-structure exhibit the most promising electrocatalytic activity and stability owing to the fine-tuning of their surface adsorption properties via a synergistic nearby element or domain. Finally, selected applications of the developed Ni-based HER catalysts are highlighted, such as water splitting, the chloralkali process, and microbial electrolysis cell.
Hydrogen evolution reaction (HER) through water splitting is a promising way to solve the energy short-age.Noble-metal-free HER electrocatalysts with high efficiency is very important for practical applica-tions.Herein,we prepare the Ni3S4@MoS2 electrocatalyst on carbon cloth (CC) through a two-step hy-drothermal process.The Ni3S4 nanorods are uniformly integrated with the MoS2 nanosheets,forming a hierarchical structure and heterogeneous interfaces.The fast electron transfer on the interface en-hances the kinetics of catalytic reaction.The hierarchical structure provides more exposed active sites.The Ni3S4@MoS2/CC exhibits good catalytic activity and long-term stability for HER.This work provided a practicable strategy to develop efficient electrocatalysts for HER in alkaline media. 相似文献
Tailoring of nickel-sulfur (Ni-S) intermetallic compound film electrodes for hydrogen evolution reaction in alkaline solutions was attempted by electrodeposition from a typical Watts bath containing sodium thiosulfate as sulfur source and sulfosalicylic acid as additive. The XRD analysis shows that the as-deposited Ni-S film electrode with fine morphological features comprised of intermetallic compound phase structure and amorphous phase structure. The intermetallic compound film electrodes generate a higher catalytic activity for the hydrogen evolution reaction in alkaline solution in comparison with Ni-S film electrodes comprised of amorphous phase structures, even with commercial Ni mesh or Ni/RuO2 composite electrode. 相似文献
