Efficient acidic hydrogen evolution in proton exchange membrane electrolyzers over a sulfur-doped marcasite-type electrocatalyst

Abstract

Large-scale deployment of proton exchange membrane (PEM) water electrolyzers has to overcome a cost barrier resulting from the exclusive adoption of platinum group metal (PGM) catalysts. Ideally, carbon-supported platinum used at cathode should be replaced with PGM-free catalysts, but they often undergo insufficient activity and stability subjecting to corrosive acidic conditions. Inspired by marcasite existed under acidic environments in nature, we report a sulfur doping–driven structural transformation from pyrite-type cobalt diselenide to pure marcasite counterpart. The resultant catalyst drives hydrogen evolution reaction with low overpotential of 67 millivolts at 10 milliamperes per square centimeter and exhibits no degradation after 1000 hours of testing in acid. Moreover, a PEM electrolyzer with this catalyst as cathode runs stably over 410 hours at 1 ampere per square centimeter and 60°C. The marked properties arise from sulfur doping that not only triggers formation of acid-resistant marcasite structure but also tailors electronic states (e.g., work function) for improved hydrogen diffusion and electrocatalysis.

Covalency-aided electrochemical CO2 reduction to CO on sulfide-derived Cu–Sb

“…27 Unfortunately, excessive p-block element content often results in increased *H coverage leading to prominent H 2 evolution (HER). 20,28 Thus, high performance CO 2 RR to CO demonstration on p-block doped metals with relatively weaker *CO binding ( e.g. , Ag/Au/Zn) is usually performed in non-aqueous electrolytes.…”

Constructing Interfacial Oxygen Vacancy and Ruthenium Lewis Acid–Base Pairs to Boost the Alkaline Hydrogen Evolution Reaction Kinetics

“…[2] Alkaline water electrolysis, proposed in 1789, has made significant advancements and is currently the most developed industrial technology for hydrogen production. [3] However, it still faces challenges such as high energy consumption and low conversion efficiency. [4] In alkaline media, the rate of the HER is mainly controlled by two factors: the hydrogen-adsorption free energy indicated by activity volcano plots, [5] and the water dissociation capacity in the Volmer step, which is approximately two to three orders of magnitude lower than that under acidic conditions.…”

Nitrogen-Doped Mesoporous Molybdenum Carbide Nanosheets for Efficient Alkaline Hydrogen Production

“…8−10 Hence, in search of non-noble metal catalysts with excellent catalytic activity and long-term durability for affordable hydrogen generation still remains a priority. 11,12 Molybdenum carbide implies the possibility of alternative advanced HER catalysts against noble metals owing to a similar d-band structure with platinum. This property has garnered tremendous interests to construct high-performance electrocatalysts based on molybdenum carbide composites.…”

“…Hydrogen is an ideal energy carrier with the potential to tackle worldwide energy crises and environmental issues owing to its high energy density and environmental benignity; electrocatalytic water splitting has been regarded as a more economical and sustainable method to realize large-scale hydrogen generation compared with gasification, steam reforming, and dark fermentation strategies. − But industrialized electric-driven water splitting particularly relies on catalytic activity and durability of the electrocatalysts. − To date, the platinum-based materials are still recognized as optimal catalysts for hydrogen evolution reaction (HER) in commercial electrolyzer cells due to active and robust electrocatalytic behavior, whereas low cost effectiveness and scarcity of precious metals severely restrict extensive industrial applications. − Hence, in search of non-noble metal catalysts with excellent catalytic activity and long-term durability for affordable hydrogen generation still remains a priority. , …”