High‐performance hole‐selective <scp>V<sub>2</sub>O<sub>X</sub></scp>/<scp>SiO<sub>X</sub></scp>/<scp>NiO<sub>X</sub></scp> contact for crystalline silicon solar cells
Guanlin Du, Le Li, Haiyin Zhu, Linfeng Lu, Xi Zhou, Zeyu Gu, Shan‐Ting Zhang, Xinbo Yang, Jilei Wang, Liyou Yang, Xiaoyuan Chen, Dongdong Li
Abstract
Abstract High work function vanadium oxide (V 2 O X , X < 5) is expected to induce strong upward band bending at crystalline silicon ( c ‐Si) surface thus selectively collect photogenerated hole‐carriers. However, the performance of c ‐Si solar cells employing V 2 O X ‐based hole‐selective contacts is still under expectation. Herein, we improve the hole‐selectivity of V 2 O X in combination with NiO X . The innovative V 2 O X /NiO X stack shows reduced contact resistivity but deteriorated minority carrier lifetime due to undesired interfacial reaction between V 2 O X and NiO X . Inserting an ultrathin SiO X interlayer suppresses the reaction and preserves the high work function of V 2 O X . A remarkable power conversion efficiency of 22.03% (fill factor of 83.07%) was achieved on p ‐type c ‐Si solar cells featuring a full‐area V 2 O X /SiO X /NiO X rear contact, which is so far the highest value reported for V 2 O X ‐based selective contacts. Our work highlights the significance of implementing p ‐type transition‐metal‐oxides to boost the selectivity of V 2 O X and the like. image