Related Experiment Video
Updated: Sep 10, 2025
Close-Space Sublimation-Deposited Ultra-Thin CdSeTe/CdTe Solar Cells for Enhanced Short-Circuit Current Density and Photoluminescence
Published on: March 6, 2020
Dual-Functional GeSe-Se Coselenization Enabling Synergistic Defect-Interface Engineering for High-Efficiency
Sheng Liu1, Jingling Liu1, Ying Xue1
1Key Laboratory for Special Functional Materials of Ministry of Education, National and Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China.
None:
Flexible Cu2ZnSnSe4 (CZTSe) solar cells hold great potential for low-cost green fabrication and portable applications, yet electrodeposited devices suffer from low efficiency (∼6% vs 12.84% for solution-processed ones), primarily due to defect-induced nonradiative recombination and carrier loss at back interfaces. Herein, a dual-functional GeSe-Se coselenization strategy is proposed to simultaneously achieve defect regulation and back-interface engineering. Ge substitution for Sn during selenization induces lattice contraction, effectively suppressing Sn-related deep defects and band-tail states while minimizing the secondary phase. Simultaneously, Ge diffuses into the MoSe2 interface layer to optimize the energy-level alignment and reduce nonradiative recombination. Consequently, the optimized flexible CZTSe solar cells achieve a record efficiency of 9.01%, the highest among electrodeposited flexible CZTSe devices. This study elucidates the synergistic role of Ge in simultaneously mitigating bulk defects and refining interfacial energetics, highlighting a remarkable achievement for electrodeposition-based flexible CZTSe solar cells.
