Gold hydrogen: A review of an emerging energy resource evaluated through geochemical and computational advances

Naturally occurring geological hydrogen, termed “gold hydrogen” within recent color-based classifications, is an emerging low-carbon energy resource. However, its geochemical origins, subsurface accumulation, and transport mechanisms remain elusive. This review provides a targeted synthesis of gold hydrogen from two complementary perspectives: (i) geochemical generation and migration mechanisms, and (ii) computational modelling of hydrogen formation and transport in relevant minerals. First, hydrogen genesis from various sources such as serpentinization, radiolysis, soil-related processes, and other rock-water interactions has been thoroughly reviewed with emphasis on reaction pathways and controlling variables. Second, computational modelling are systematically evaluated, progressing from early simplified mineral models to contemporary models that probe water-mineral interaction with specific mineral crystallographic surfaces, the catalytic effect of Fe 2+ ions, possible hydrogen formation pathways, and hydrogen diffusion kinetics using various simulation methods. This is complemented by a systematic synthesis of experimental investigations into hydrogen migration mechanisms in key minerals such as natural olivine and synthetic forsterite, as well as the effect of mineral defects and electron trapping (polaron formation) on hydrogen transport. Despite promising progress, significant challenges persist in fully elucidating hydrogen migration mechanisms and reconciling discrepancies between theoretical predictions and experimental observations. We argue that addressing these challenges necessitates a multidisciplinary framework. A path forward lies in the development of laboratory-scale reactor models, which can serve as test-beds to validate computational simulations, refine geochemical hypothesis, and ultimately enable predictive models of hydrogen generation and transport. This integrated approach is essential to accelerate the development of gold hydrogen as a scalable low-carbon fuel. • Reviewed genesis of gold hydrogen from various processes. • Analyzed the evolution of computational models. • Critically discussed experimental evidence on hydrogen migration. • Proposed an interdisciplinary framework for predictive modelling.