Themed collection Energy Frontiers: Hydrogen

A perspective with an explicit account of the appropriate screening of water splitting electrocatalysts advocating dos and don’ts!

The envisioned role of hydrogen in the energy transition – or the concept of a hydrogen economy – has varied through the years.

The transition to green ammonia is necessary, but conventional catalysts perform poorly under ‘green’ reaction conditions. We provide a perspective on the recent progress in developing more efficient catalysts for lower temperatures and pressures.

Natural gas based hydrogen production with carbon capture and storage is referred to as blue hydrogen.

This study assesses research and development needs for direct seawater electrolysis from energy, cost and environmental aspects and presents a forward-looking perspective on future R&D priorities in desalination and electrolysis technologies.

Understanding the durability-limiting factors of anion exchange membrane water electrolyzers operating under pure water-, KOH- and K₂CO₃-fed conditions.

This article identifies and discusses the scientific challenges of hydrogen storage in porous media for safe and efficient large-scale energy storage to enable a global hydrogen economy.

Urea electrolysis is a promising energy-saving avenue for hydrogen production owing to the low cell voltage, wastewater remediation and abundant electrocatalysts.

This review summarizes the superiorities and utilizations of 2D materials for photoelectrochemical water splitting including transition metal dichalcogenides, graphene, graphdiyne, black phosphorus, layered double hydroxides, g-C₃N₄, and MXenes.

Hydrogen (H₂) production along with CCUS (carbon capture, utilization, and storage) are two key areas for transition to net-zero emission. Carbon-neutral liquid e-fuels produced from H₂ and captured CO₂ are practical alternatives to fossil fuels.

Hydrogen is emerging as one of the most promising energy carriers for a decarbonised global energy system.

Replacing fossil fuels with energy sources and carriers that are sustainable, environmentally benign, and affordable is amongst the most pressing challenges for future socio-economic development.

Nanocomposite catalysts have dramatically improved hydrogen generation from several hydrogen-rich sources in the liquid phase toward the transport of this green fuel.

This review summarizes recent advances relating to transition metal sulfide (TMS)-based bifunctional electrocatalysts, providing guidelines for the design and fabrication of TMS-based catalysts for practical application in water electrolysis.

Hydrogen production using water electrolysers equipped with an anion exchange membrane, a pure water feed and cheap components (catalysts and bipolar plates) can challenge proton exchange membrane electrolysis systems as the state of the art.

The fundamentals related to the oxygen evolution reaction and catalyst design are summarized and discussed.

This article provides a comprehensive review of the latest progress, challenges and recommended future research related to metal-free photocatalysts for hydrogen production via water-splitting.

This review describes recently developed self-transfer hydrogenolysis for the lignin depolymerization using itself as a hydrogen donor and proposes a concept of endogenous hydrogen efficiency to assess the utilization rate of endogenous hydrogen.

Environmental impacts and net-energy of hydrogen production via solar-electrolysis are highly sensitive to operating constraints and context specific variances.

The future of green ammonia as long-term energy storage relies on the replacement of the conventional CO₂ intensive methane-fed Haber–Bosch process by distributed and agile ones aligned to the geographically isolated and intermittent renewable energy.

One-step electrodeposition strategy is employed to synthesis the Ni–Mn–Se electrocatalyst, exhibiting remarkable hydrogen evolution and urea oxidation reactions catalytic activity and stability at large current densities even superior to platinum.

We analyse the potential of solar hydrogen production in remote and cold world regions such as Antarctica and quantify the efficiency benefits of thermal coupling.

Using inspiration from biological cofactors, the reversible storage of hydrogen on a supporting dihydrazonopyrrole ligand enables catalytic hydrogenation reactivity with nickel.

Exceptionally high OER & HER performances were achieved by rationally designing the electrode structure of non-noble NiFe materials.

The covalent assembly between a cobalt diimine-dioxime complex and a fullerenic moiety results in enhanced catalytic properties in terms of overpotential requirement for H₂ evolution and allows its integration in an operating photocathode.

RuRhPdIrPt high-entropy-alloy nanoparticles with a broad and featureless valence band spectrum show high hydrogen evolution reaction activity.

The synthesis and decomposition of formic acid (FA) in aqueous triethylamine (NEt₃) with solid molecular phosphine catalysts is demonstrated.

Key performance characteristics of Proton Exchange Membrane (PEMFC) and Solid Oxide Fuel Cell (SOFC) are compared with emphasis on the sustainability of energy pathways showing that hydrogen for use in PEMFC is best supplied from renewable hydrogen.

The band edges of GeI₂/C₂N vdW are favourable to generate H₂ at pH 0 to 9 with transition from a type-II indirect to type-I direct bandgap semiconductor under tensile biaxial strain.

An organometal halide perovskite supported Pt single-atom photocatalyst is developed for efficient H₂ evolution with a superb STH of 4.50%.

The g-C₃N₄ with dual defect sites exhibits excellent photocatalytic H₂O₂ generation activity and selectivity, and the key role of each defect site in the surface reaction mechanism is revealed.

Strain engineering can regulate the electronic structure of the catalyst and then boosts the catalytic activity of Pt-doped Ti₂CF₂ (Pt-V_F-Ti₂CF₂).

The design and construction of advanced functional structures for photocatalysts has been proven to be an extremely effective approach to greatly enhance their properties toward higher solar-driven water splitting efficiency.

Novel CuNi bimetal-modified ZnIn₂S₄ photocatalysts with enhanced photocatalytic hydrogen evolution performance have been explored. The possible mechanism of the synergistic effect and spillover effect between Cu and Ni were proposed.

We develop and demonstrate a comprehensive data-driven screening protocol with co-validation between experiment and theory to maximize the success rate of materials discovery for photocatalytic hydrogen generation.

Non-confined MgH₂ nanoparticles of 4–5 nm diameter enable reversible storage of hydrogen up to 6.7 wt% at 30 °C.

Incorporation of conducting polymers (CPs) with TiO₂ is considered a promising pathway toward the fabrication of highly efficient non-metal based photocatalysts.

Pyrene based conjugated microporous polymers (CMPs) as photocatalysts with promising H₂ production efficiencies and very high stability.

A common strategy is developed to exfoliate bulk CPPs into nanosheets for highly efficient PHP performance.

The solar to hydrogen (STH) efficiency of photovoltaic-electrolysis (PV-E) setups are a key parameter to lower the cost of green hydrogen produced.

The Mg₂Ni/Mg₂NiH₄ formed in the original position in process of hydrogen absorption and dehydrogenation is distributed around Mg/MgH₂, which accelerates the rate of hydrogen absorption and dehydrogenation.

We developed a facile, yet general, approach for preparing Li–fluorine codoped porous carbon nanofiber (Li–F–PCNF) composites, which showed excellent hydrogen storage performance.

We quantify the technical and environmental performance of clean hydrogen production (with CCS) by linking detailed process simulation with LCA.

In operando XAS investigation on FeCoNi-based thin film unravels that Fe³⁺-assisted water dissociation promotes the formation of Co²⁺–μ-H–Ni³⁺ species, and the conductive character of Co²⁺Ni³⁺-oxide matrix facilitates the coupling of adjacent [Fe⁴⁺O/Fe³⁺–O˙] motifs.

A two-phase high-entropy oxide with orange color and good light absorbance is introduced as a photocatalyst for hydrogen production.

The Ru supported on Porphyra-CQDs exhibited better dispersibility and the highest activity compared with biomass Porphyra and Porphyra activated carbon owing to the strong coordination interactions between Ru and CQDs.