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Updated: Dec 19, 2025

Residue-Free Fabrication of van der Waals Heterostructures of Two-Dimensional Materials
Published on: July 18, 2025
Macro van der Waals p-n heterojunction based on SnSe and SnSe2
Yujia Zhong1, Li Zhang2, Wenduo Chen1
1State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
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Van der Waals (vdW) heterojunctions based on two-dimensional materials have attracted great attention in emerging photoelectronics. However, the low-efficiency growth of single crystals significantly limits the practical applications of vdW heterojunctions. Here, we report a macro SnSe/SnSe2 heterojunction assembled by conformally transferring in-plane p-type SnSe on n-type SnSe2 synthesized by chemical vapor deposition. With well-matched band alignments, the SnSe/SnSe2 vdW photodetector exhibits dramatically enhanced performance with a responsivity of 17.5 mA W-1 and a response time of 17 ms, comparing with the sole SnSe or SnSe2 based photodetector.
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