Heteroatom doping enables hydrogen spillover via H⁺/e⁻ diffusion pathways on a non-reducible metal oxide

Shun K., Mori K., Kidawara T., et al. Heteroatom doping enables hydrogen spillover via H⁺/e⁻ diffusion pathways on a non-reducible metal oxide. Nature Communications 15, 6403 (2024); https://doi.org/10.1038/S41467-024-50217-Z.Hydrogen spillover, the simultaneous diffusion of protons (H⁺) and electrons (e⁻) is considered to be applicable to ubiquitous technologies related to hydrogen but limited to over reducible metal oxides. The present work demonstrates that a non-reducible MgO with heteroatom Al dopants (Al–MgO) allows hydrogen spillover in the same way as reducible metal oxides. Furthermore, a H⁺ storage capacity of this material owing to hydrogen spillover is more than three times greater than those of various standard metal oxides based on H⁺ transport channels within its bulk region. Atomic hydrogen diffuses over the non-reducible Al–MgO produces active H⁺-e⁻ pairs, as also occurs on reducible metal oxides, to enhance the catalytic performance of Ni during CO2 hydrogenation. The H⁺ and e⁻ diffusion pathways generated by the heteroatom Al doping are disentangled based on systematic characterizations and calculations. This work provides a new strategy for designing functional materials intended to hydrogen spillover for diverse applications in a future hydrogen-based society

Heteroatom doping enables hydrogen spillover via H+/e− diffusion pathways on a non-reducible metal oxide

Abstract Hydrogen spillover, the simultaneous diffusion of protons (H+) and electrons (e−) is considered to be applicable to ubiquitous technologies related to hydrogen but limited to over reducible metal oxides. The present work demonstrates that a non-reducible MgO with heteroatom Al dopants (Al–MgO) allows hydrogen spillover in the same way as reducible metal oxides. Furthermore, a H+ storage capacity of this material owing to hydrogen spillover is more than three times greater than those of various standard metal oxides based on H+ transport channels within its bulk region. Atomic hydrogen diffuses over the non-reducible Al–MgO produces active H+-e− pairs, as also occurs on reducible metal oxides, to enhance the catalytic performance of Ni during CO2 hydrogenation. The H+ and e− diffusion pathways generated by the heteroatom Al doping are disentangled based on systematic characterizations and calculations. This work provides a new strategy for designing functional materials intended to hydrogen spillover for diverse applications in a future hydrogen-based society