Proton-conductive coordination polymer glass for solid-state anhydrous proton batteries†

Designing solid-state electrolytes for proton batteries at moderate temperatures is challenging as most solid-state proton conductors suffer from poor moldability and thermal stability. Crystal-glass transformation of coordination polymers (CPs) and metal-organic frameworks (MOFs) via melt-quenching offers diverse accessibility to unique properties as well as processing abilities. Here, we synthesized a glassy-state CP, [Zn-3(H2PO4)(6)(H2O)(3)](1,2,3-benzotriazole), that exhibited a low melting temperature (114 degrees C) and a high anhydrous single-ion proton conductivity (8.0 x 10(-3) S cm(-1) at 120 degrees C). Converting crystalline CPs to their glassy-state counterparts via melt-quenching not only initiated an isotropic disordered domain that enhanced H+ dynamics, but also generated an immersive interface that was beneficial for solid electrolyte applications. Finally, we demonstrated the first example of a rechargeable all-solid-state H+ battery utilizing the new glassy-state CP, which exhibited a wide operating-temperature range of 25 to 110 degrees C.

Automated summary

Designing solid-state electrolytes for proton batteries at moderate temperatures is challenging due to poor moldability and thermal stability of most solid-state proton conductors. By converting crystalline coordination polymers (CPs) to glassy-state counterparts via melt-quenching, a glassy-state CP with low melting temperature and high proton conductivity was synthesized, showing potential for solid electrolyte applications. The first rechargeable all-solid-state H+ battery utilizing the new glassy-state CP was demonstrated, with a wide operating-temperature range of 25 to 110 degrees C.