A family of homologous metal heteromaterials with chemically bonded metallic interface.

Heteromaterials made of two different components have been widely studied; their interfacial bonding is essential to control their properties. How to prepare a chemically bonded metallic interface remains elusive, despite its importance for structural and functional materials. Here we synthesized a family of homologous metal heteromaterials (HMHs) featuring chemically bonded metallic interfaces, which endow them with strong interfacial binding forces and metallic conductivity. These features stem from delocalized electronic states and a uniformly distributed electric field across the interface of HMHs. We synthesized and high-throughput screened a family of HMHs comprising four categories and 20 materials. As an application example, we show that HMHs operate stably in a water electrolyzer with a decay rate of 1.06 μV h at high current density over 1000 h, thanks to the above two interface properties. To our knowledge, this is the lowest decay rate reported to date, surpassing the target of the U.S. Department of Energy for 2040.