Self-Powered Electrocatalytic Aldehyde Reforming Fuel Cell for Sustainable H2 Generation with ∼200% Faradaic Efficiency.

Formaldehyde (HCHO), a promising yet challenging hydrogen carrier, offers a unique opportunity for efficient hydrogen generation through electro-oxidation, simultaneously eliminating harmful HCHO and contributing to environmental sustainability. This study rises to the challenge by pioneering a hybrid acid/alkali formaldehyde hydrogen production fuel cell (h-AAFHFC), an integrated system that integrates anodic partial electro-reforming of aldehydes at low potential with the cathodic hydrogen evolution reaction (HER). The device introduces a new self-powered paradigm for hydrogen generation, driven by electrochemical neutralization energy (ENE), featuring high Faradaic efficiency for hydrogen production, co-generation of electricity, and HCOOH. The h-AAFHFC attains an open-circuit voltage (OCV) of 1.11 V and a peak power density of 94 mW cm-2, enabling simultaneous hydrogen production at both electrodes with an extraordinary Faradaic efficiency of approximately 200%. This breakthrough marks a transformative shift, moving from traditional electricity-driven systems to self-sustaining H2 generation. Our work demonstrates a promising pathway for sustainable hydrogen production, advancing the potential of clean hydrogen energy technologies.