Discovery of the Zintl-phosphide BaCd2P2 as a long carrier lifetime and stable solar absorber

Thin-film photovoltaics (PV) offers a path to decarbonize global energy production. Unfortunately, existing thin-film solar absorbers have major issues associated with either elemental abundance, stability, or performance. Entirely new and disruptive materials platforms are rarely discovered, and their search is traditionally slow and serendipitous. Here, we report a first-principles high-throughput (HT) computational screening for new solar absorbers among 40,000 known inorganic materials. Next to band gap and carrier effective masses, we also use computed intrinsic defects as they can limit the carrier lifetime. We identify the Zintl-phosphide BaCd2P2 as a potential high-efficiency solar absorber. Follow-up experiments confirm the promises of BaCd2P2, highlighting an optimal band gap, bright photoluminescence (PL), and long carrier lifetime, even in unoptimized powder samples. Importantly, BaCd2P2 contains no critical elements and is stable in air and water. Our work demonstrates how computational screening combined with experiments can accelerate the search for photovoltaic materials. [Display omitted] •Computational screening for solar absorbers among 40,000 known inorganic materials•Inclusion of intrinsic defects and carrier lifetime in the screening•Identification of a novel solar absorber, BaCd2P2, with promising experimental properties Thin-film PV provides a path to carbon-free electricity generation. However, existing thin-film solar absorbers have major issues associated with either elemental abundance, stability, or performance, limiting large-scale deployment of thin-film PV. Here, we use computational screening to search for new solar absorbers among 40,000 known inorganic materials. Because point defects are known to promote carrier recombination (and losses), we include them in the screening. We computationally discover a promising low-cost solar absorber, the Zintl-phosphide BaCd2P2, and confirm its properties experimentally. This material combines attractive optoelectronic properties with slow carrier recombination and high stability. Our work not only opens an avenue for a new class of thin-film solar absorbers but also demonstrates how computational screening combined with experiments can accelerate the search for PV materials, moving the field away from serendipitous materials discovery. This work reports a large computational screening for new thin-film solar absorbers among 40,000 known inorganic materials. The screening reveals that