A cracked carbon matrix decorated with amorphous IrO_x for boosting the oxygen evolution reaction in electrochemical water splitting

Numerous studies have been performed to develop better materials and systems to boost H₂ production by water splitting. IrO₂ and Ti felt have been conventionally used in proton exchange membrane water electrolyzers (PEMWE) as anode catalysts and porous transport layers (PTLs), respectively. In this study, a cracked carbon matrix (CM) and amorphous IrO_x nanoparticles were introduced to overcome the limitations of the current materials. Amorphous IrO_x protected by thin carbon shells exhibited higher electrocatalytic activity for the O₂ evolution reaction than commercial IrO₂ and ensured sufficient durability under highly oxidative conditions. CM provided a sufficient surface area to disperse the IrO_x nanoparticles, and its cracked nature facilitated the transport of electrolytes and produced O₂. These merits enabled PEMWE to achieve 1 A cm⁻² at a cell voltage of 1.64 V without severe degradation.