Pressure-Assisted Ceramic Processing of Metal Halide Perovskites

Increasing demand for metal halide perovskites in applications beyond photovoltaics (e.g., hard radiation detection) necessitates hundreds of microns to millimeters thick active layers for optimal performance. This review critically assesses low-temperature, pressure-assisted ceramic processing as a pivotal technique to fabricate dense, polycrystalline wafers with precisely controlled macroscopic dimensions as well as microstructural properties. Exploiting the soft ionic bonding and subsequent plasticity of metal halide perovskites, pressure-assisted ceramic processing can achieve rapid densification at drastically reduced temperatures (≲100 °C) compared to common oxide ceramics (≳1000 °C). As a direct result, metal halide perovskite ceramics can be manufactured using cost-effective pressure-assisted ceramic processing methods (e.g., low-temperature uniaxial pressing). However, a definitive understanding of the intricate relationship between sintering parameters (temperature, pressure, and powder characteristics) and the resulting microstructural attributes (pore/grain size and distribution, relative density, porosity, and crystallinity) and optoelectronic responses remains a knowledge gap. To metal halide perovskite experts, the aim is to emphasize the considerable advantages of pressure-assisted ceramic processing, and to expert ceramists, the aim is to demonstrate that metal halide perovskites offer a compelling material class for established ceramic processing techniques. Bridging the knowledge between these two distinct areas of expertise will help drive transformative progress in metal halide perovskite-based technologies.