Efforts to enhance the efficiency and sustainability of chemical transformations, crucial for achieving net-zero targets, have led to the advancement of the water–gas shift reaction (WGS). This critical reaction in hydrogen production has now seen innovation through the 'memory reactor' concept, which exploits ABO3−δ perovskite materials to drive conversions beyond equilibrium values. By utilizing neutron diffraction studies, researchers have gained precise insights into oxygen chemical potential gradients within the reactor, enabling close monitoring of the conversion process. The memory reactor's unique design allows for the production of separate hydrogen and CO2 streams, significantly improving overall efficiency. Furthermore, the reactor's ability to operate stably over numerous cycles and switch between different modes highlights its versatility for diverse applications. By implementing controlled OCM conversion in each half cycle, the memory reactor achieves remarkable gas conversions that outperform traditional thermodynamic approaches. This innovative approach represents a significant step forward in hydrogen production technology, offering promise for a more sustainable and efficient future.