Achieving zT ≥ 1.0 in a Cd ₃ P ₂ -Based System via Alloying Minor Arsenic

In this work, we report the enhanced thermoelectric performance of the Cd 3 P 2 system achieved through alloying minor arsenic. The Cd 3 P 2 -based material (Cd 3 P 1.8 As 0.2 ) achieves a peak zT exceeding 1.0 and an average zT of 0.59, comprehensively surpassing the performance of the pristine Cd 3 P 2 compound. Such enhanced performance is attributed to the partial decoupling between electrical and thermal transport, where the reduced effective mass enhances carrier mobility, while As-induced defect scattering and increased lattice anharmonicity effectively suppress the lattice thermal conductivity. Theoretical analysis suggests further potential for improvement, thereby expanding the application prospects of this system.