Hydrogen Spillover Mechanisms in Catalytic Systems

Hydrogen spillover describes the migration of activated hydrogen atoms or protons from metal nanoparticles onto adjacent support materials, enabling hydrogenation reactions at remote sites. This phenomenon underpins advances in heterogeneous catalysis, hydrogen storage and selective reduction processes. Migrated hydrogen species traverse reducible oxides, non-reducible supports and porous frameworks via coupled proton–electron pathways or surface-mediated hops. Control over spillover distance, energetics and interfacial chemistry has revealed routes to tune catalyst selectivity, activity and stability. Recent work has shown that water molecules, organic mediators and heteroatom dopants can lower migration barriers, while nanoscale confinement and signal-amplification techniques elucidate dynamic spillover events in real time. Understanding these mechanisms is vital for designing next-generation catalysts that address global challenges in clean energy, fine-chemical manufacture and sustainable process intensification.

Research from Nature Portfolio

Water-assisted spillover in metal–organic frameworks has been demonstrated by encapsulating platinum nanoparticles within MOF-801, where adsorbed water lowers the hydrogen migration barrier and extends the reactive zone to over 100 nm, dramatically boosting hydrogenation rates and antitoxicity performance. Advanced spectroscopic methods have enabled real-time visualisation of interfacial hydrogen replenishment in Pd@ZIF-8 composites through modular signal amplification, in situ X-ray absorption and surface-enhanced Raman measurements coupled to molecular dynamics, revealing dynamic spillover pathways that drive semihydrogenation selectivity. In another study, heteroatom doping of MgO with aluminium has been shown to introduce proton–electron diffusion channels on a non-reducible oxide, affording H+ storage capacities and CO2 hydrogenation activity comparable to reducible metal oxides while opening a new design paradigm for spillover-enabled materials.

Hydrogen Spillover Mechanisms in Catalytic Systems publication trend

The graph below shows the total number of articles in hydrogen spillover mechanisms in catalytic systems across all publications each year (not limited to Nature Index journals).

Technical terms

Hydrogen spillover: The surface migration of activated hydrogen atoms or protons from a metal site onto a support material.

Reducible oxide: A metal-oxide support capable of changing oxidation state and facilitating proton–electron coupled migration.

Non-reducible oxide: A support material that does not readily change oxidation state and often requires mediators or dopants for spillover.

Metal–organic framework (MOF): A porous crystalline network of metal nodes and organic linkers, serving as a tunable support for metal nanoparticles.

Proton–electron coupled migration: A mechanism by which protons and electrons move simultaneously through a support to sustain hydrogen spillover.

References

1. Water-assisted hydrogen spillover in Pt nanoparticle-based metal–organic framework composites. Nature Communications (2023).
2. Spectroscopic visualization of reversible hydrogen spillover between palladium and metal–organic frameworks toward catalytic semihydrogenation. Nature Communications (2024).
3. Heteroatom doping enables hydrogen spillover via H+/e− diffusion pathways on a non-reducible metal oxide. Nature Communications (2024).
4. Synthesis of a binary alloy nanoparticle catalyst with an immiscible combination of Rh and Cu assisted by hydrogen spillover on a TiO 2 support. Chemical Science (2020).
5. Sub-nanometric High-Entropy Alloy Cluster: Hydrogen Spillover Driven Synthesis on CeO2 and Structural Reversibility. JACS Au (2023).
6. Evolution of multiple spillover hydrogen species on anatase titanium dioxide. Cell Reports Physical Science (2022).