The effect of Processing on Hybrid Organic-Inorganic Perovskites and Solid-State Electrolytes for Use in Energy Production and Storage Devices

Abstract

Hybrid organic-inorganic perovskites that are used in energy production devices are discussed, as are solid-state Li-ion electrolytes that are used in energy storage devices. Of the these electrolytes, Li$_7$P$_3$S$_{11}$ is promising, displaying high ionic conductivities; it is sensitive to air exposure. Laser processed pellets of Li$_7$P$_3$S$_{11}$ pellets were prepared to bolster its hydrolytic stability. Such laser processing resulted in changes to the surface morphology and chemical composition of the electrolyte. The degree of morphological and chemical change is a function of the energy supplied to the sample, which can be controlled through adjustment of laser processing parameters. Fabricating batteries with thin electrolyte sheets increases energy density and lowers internal resistance; thus, solution processing pathways for Li$_7$P$_3$S$_{11}$ were explored, and chemical compatibility of this electrolyte with various solvents was assessed. We attempt to use propylamine to synthesis and deposit the electrolyte; side reactions in this solvent and low ionic conductivity of the resulted solid compromised the utility of several solvents studied. In a separate study the role of CsI was elucidated in solution in solution via UV-Vis spectroscopy and a series of NMR experiments. Evidence was obtained that supports perovskite pre-organization in precursor solutions containing CsI, which may improve crystallization pathways to bolster the solid-state material properties.