TY - JOUR AB - SnSe has emerged as one of the most promising materials for thermoelectric energy conversion due to its extraordinary performance in its single-crystal form and its low-cost constituent elements. However, to achieve an economic impact, the polycrystalline counterpart needs to replicate the performance of the single crystal. Herein, we optimize the thermoelectric performance of polycrystalline SnSe produced by consolidating solution-processed and surface-engineered SnSe particles. In particular, the SnSe particles are coated with CdSe molecular complexes that crystallize during the sintering process, forming CdSe nanoparticles. The presence of CdSe nanoparticles inhibits SnSe grain growth during the consolidation step due to Zener pinning, yielding a material with a high density of grain boundaries. Moreover, the resulting SnSe–CdSe nanocomposites present a large number of defects at different length scales, which significantly reduce the thermal conductivity. The produced SnSe–CdSe nanocomposites exhibit thermoelectric figures of merit up to 2.2 at 786 K, which is among the highest reported for solution-processed SnSe. AU - Liu, Yu AU - Calcabrini, Mariano AU - Yu, Yuan AU - Lee, Seungho AU - Chang, Cheng AU - David, Jérémy AU - Ghosh, Tanmoy AU - Spadaro, Maria Chiara AU - Xie, Chenyang AU - Cojocaru-Mirédin, Oana AU - Arbiol, Jordi AU - Ibáñez, Maria ID - 10042 IS - 1 JF - ACS Nano KW - tin selenide KW - nanocomposite KW - grain growth KW - Zener pinning KW - thermoelectricity KW - annealing KW - solution processing SN - 1936-0851 TI - Defect engineering in solution-processed polycrystalline SnSe leads to high thermoelectric performance VL - 16 ER -