Unveiling the Role of Intermediate Neutral Hydrogen in Bridging Moisture‐Electric Generation and Hydrogen Evolution

Abstract

ABSTRACT Harvesting renewable energy from ambient moisture into sustainable electricity represents a promising route to address global energy and climate challenges. However, the moisture energy utilization is low in existing moisture‐electric generators (MEGs) technologies. Here, we report a carrier‐type–engineered graphene oxide (GO)–based MEG that not only generates electricity from moisture but also drives clean hydrogen production via electrochemical water splitting. The optimized device delivers a steady voltage output of 0.90 V and an ultra‐high current density of 0.25 mA∙cm −2 at 80% relative humidity, maintaining excellent stability for two weeks. Importantly, we first reveal that the proton–electron recombination during MEG discharge produces abundant neutral hydrogen atoms absorbed on the carbon nanotube substrate, which subsequently act as highly active species for the hydrogen evolution reaction (HER), achieving a remarkably low overpotential of ∼20 mV. The present work marks the first demonstration of hydrogen generation directly coupled with MEG discharge via cascade utilization of intermediate neutral hydrogen molecules. Furthermore, the device can be rejuvenated through a recycling treatment, enabling cyclic operation. This study not only advances the fundamental understanding of charge transfer and proton dynamics in MEGs but also introduces a new paradigm for coupling ambient‐energy harvesting with sustainable hydrogen production.