Electrocatalytic Hydrogen Evolution in Two-Dimensional Materials

The electrocatalytic hydrogen evolution reaction (HER) lies at the heart of sustainable energy schemes, enabling the conversion of water into green hydrogen under mild conditions. Two-dimensional (2D) materials – atomically thin crystals including transition metal dichalcogenides, MXenes, metal phosphides, boron nitride and graphene derivatives – offer high specific surface area and unique electronic properties that can be harnessed for HER. In these systems, catalytic activity often originates at edges, defects, basal planes or phase boundaries. Electronic structure tuning by chemical doping, strain engineering, phase control or external fields can lower the energy barrier for proton reduction, reducing overpotential and improving kinetics as reflected in Tafel slopes and exchange current densities. Recent advances have demonstrated that intrinsic properties of 2D materials – such as modifiable band structure, mechanical flexibility and emergent phenomena in twisted lattices – can be exploited to approach or even rival the performance of precious-metal electrodes. Integrating these catalysts into practical devices, from water-splitting cells to photoelectrochemical modules, has underlined their global potential for decentralised hydrogen production, fuel-cell technologies and energy storage. Continued progress hinges on understanding reaction mechanisms at the atomic scale and on scalable synthesis routes that preserve the desired 2D architecture.

Research from Nature Portfolio

Recent studies have shown that external electric fields can dynamically polarise charge at single-atom catalyst sites anchored on 2D crystals, modulating the kinetics of the rate-determining step and boosting HER activity. By applying oriented fields, researchers achieved significant reductions in overpotential and enhanced current densities, demonstrating a versatile strategy to emulate enzymatic active-site tuning. Another work introduced moiré superlattices in mechanically flexible WS₂ nanobelts, where twist-induced periodicity creates new active sites with near-thermoneutral hydrogen adsorption energies. These twisted bilayers exhibit both superior conductivity and exceptional electrocatalytic performance, highlighting the potential of twistronics in catalyst design. As a foundational contribution, a one-step hydrazine treatment of MoOx/MoS₂ core-shell nanowires and MoS₂ sheets was shown to electron-dope the layers and reduce the MoOx core, leading to a tenfold increase in current density and marked improvements in overpotential and Tafel slope. Together, these works underline electronic modulation – whether by chemical doping, lattice twisting or field polarisation – as a unifying theme for advancing 2D electrocatalysts.

Electrocatalytic Hydrogen Evolution in Two-Dimensional Materials publication trend

The graph below shows the total number of articles in electrocatalytic hydrogen evolution in two-dimensional materials across all publications each year (not limited to Nature Index journals).

Technical terms

Electrocatalytic hydrogen evolution reaction (HER): The electrochemical process in which protons are reduced at a cathode to form molecular hydrogen, typically measured by overpotential and Tafel slope.

Two-dimensional materials: Crystalline solids consisting of a single layer or few layers of atoms, exhibiting unique surface and electronic properties distinct from their bulk counterparts.

Overpotential: The additional potential beyond the thermodynamic requirement needed to drive an electrochemical reaction at a specified current density.

Tafel slope: A parameter describing the relationship between overpotential and the logarithm of current density, indicative of reaction kinetics and the rate-determining step.

Moiré superlattice: A periodic pattern that emerges when two crystalline layers are overlaid with a small twist angle, leading to new electronic states and catalytic sites.

Single-atom catalyst: A catalytic system where isolated metal atoms are dispersed on a support, maximising atomic utilisation and enabling precise control of active sites.

Basal plane: The flat, atomically smooth face of a layered 2D material, which may host active sites when appropriately modified or defect-engineered.

References

1. Boosting the performance of single-atom catalysts via external electric field polarization. Nature Communications (2022).
2. WS2 moiré superlattices derived from mechanical flexibility for hydrogen evolution reaction. Nature Communications (2021).
3. Efficient hydrogen evolution in transition metal dichalcogenides via a simple one-step hydrazine reaction. Nature Communications (2016).
4. Deformable Catalytic Material Derived from Mechanical Flexibility for Hydrogen Evolution Reaction. Nano-Micro Letters (2023).
5. Basal-Plane Catalytic Activity of Layered Metallic Transition Metal Ditellurides for the Hydrogen Evolution Reaction. Applied Sciences (2020).
6. Metal support effects in electrocatalysis at hexagonal boron nitride. Chemical Communications (2019).