Towards the high-throughput synthesis of bulk materials: thermoelectric PbTe–PbSe–SnTe–SnSe alloys

The experimental realization of new functional materials is a complex optimization problem that would vastly benefit from the application of high-throughput methodologies. In this work, we adapt bulk ceramic processing for high-throughput integration, with a focus on producing high-quality thermoelectric materials. We also monitor the time and effort cost per sample, providing insight for where additional engineering can further increase throughput. Through parallelization and automation, we achieve a 5–10× increase in synthetic speed, allowing the generation of a 121 sample alloy map within the PbTe–PbSe–SnTe–SnSe system. Despite heavy investment from the thermoelectric community, prior literature exclusively focuses on intuitive pseudobinary combinations within the PbTe–PbSe–SnTe–SnSe alloys. Our intuition–agnostic mapping, however, has enabled us to identify compositions with anomalous, non-monotonic changes in the thermoelectric transport. The newly discovered trends (e.g. high mobility alloys, extended band-inversion region) do not lie on the intuitive pseudobinary combinations – exemplifying the value of unbiased high-throughput methods. Additionally, as our methods were chosen explicitly to preserve sample quality, our solubility limits and room-temperature thermoelectric transport are also in excellent agreement with available literature. Ultimately, this work demonstrates that high-throughput methods are a potent tool for the accelerated optimization and realization of new functional materials.