Hydrogen production from water electrolysis: role of catalysts

Abstract

As a promising substitute for fossil fuels, hydrogen has emerged as a clean and renewable energy. A key challenge is the efficient production of hydrogen to meet the commercial-scale demand of hydrogen. Water splitting electrolysis is a promising pathway to achieve the efficient hydrogen production in terms of energy conversion and storage in which catalysis or electrocatalysis plays a critical role. The development of active, stable, and low-cost catalysts or electrocatalysts is an essential prerequisite for achieving the desired electrocatalytic hydrogen production from water splitting for practical use, which constitutes the central focus of this review. It will start with an introduction of the water splitting performance evaluation of various electrocatalysts in terms of activity, stability, and efficiency. This will be followed by outlining current knowledge on the two half-cell reactions, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), in terms of reaction mechanisms in alkaline and acidic media. Recent advances in the design and preparation of nanostructured noble-metal and non-noble metal-based electrocatalysts will be discussed. New strategies and insights in exploring the synergistic structure, morphology, composition, and active sites of the nanostructured electrocatalysts for increasing the electrocatalytic activity and stability in HER and OER will be highlighted. Finally, future challenges and perspectives in the design of active and robust electrocatalysts for HER and OER towards efficient production of hydrogen from water splitting electrolysis will also be outlined.

Net Zero and Catalysis: How Neutrons Can Help

“…The only truly "green" way to make H 2 is by water splitting, with the energy required generated by renewables or nuclear power. There are demonstration systems that use the reaction between a high temperature metal salt and water [30], but the most obvious way to generate H 2 is by electrolysis of water [31]. Unfortunately, current electrolysers are not very efficient [32].…”

Thermocatalytic Hydrogen Production Through Decomposition of Methane-A Review

“…Furthermore, because of the formation of carbon-free products, there is a significant lowering of greenhouse gas production in contrast to the traditional methods ( Ashok et al, 2008a ). It has also been reported that hydrogen production through this method reduces CO x emission by about 27% and can also reduce the global climatic effects ( Weger et al, 2017 ; Wang et al, 2021a ). The decomposition of methane requires a large amount of energy, almost equivalent to its formation.…”

“…Even pathways like hydrogen production via splitting of water using electricity have gained a widespread attraction among the scientific community ( Figure 2 ) ( Wang et al, 2021a ). Renewable resources or non-renewable resources are used as feedstock during the electricity driven water splitting ( Rozzi et al, 2020 ).…”

“…Renewable resources or non-renewable resources are used as feedstock during the electricity driven water splitting ( Rozzi et al, 2020 ). During this reaction, there are two major half-cell reactions taking place: one in which reduction of water occurs at the cathode end to give hydrogen and at the other end oxygen evolution reaction occurs that gives oxygen as the product ( Wang et al, 2021a ). This reaction occurs in the presence of catalysts like metal based or non-metal based electrocatalysts ( Wang et al, 2021a ).…”

“…During this reaction, there are two major half-cell reactions taking place: one in which reduction of water occurs at the cathode end to give hydrogen and at the other end oxygen evolution reaction occurs that gives oxygen as the product ( Wang et al, 2021a ). This reaction occurs in the presence of catalysts like metal based or non-metal based electrocatalysts ( Wang et al, 2021a ). However, when carbon-based catalysts are used during the reaction, carbon-based byproducts are sometimes formed during this process.…”