以溶膠凝膠法合成了新型高熵氧化物（HEO）光吸收層薄膜。溶膠凝膠法具有低成本、高均勻性、材料製備靈活和便於大規模生產等優點。在本研究中，以簡單的製程製造了均勻、可控的奈米結構薄膜，並且利用HEO的性質結合其薄膜特性，使其在光電感測器中成為優秀的薄膜吸收層。HEO具有無與倫比的光吸收與光響應能力，在本研究中測量了 Ag/(CrMnFeCoNi)O/n-Si 和 Ag/(CrMnFeCoNiCu)O/n-Si 的光電感測器性能。在5 V偏壓下，Ag/(CrMnFeCoNi)O/Si 光電感測器於 590 nm 波長處展現了高達 12.51 A/W 的響應度，外部量子效率（EQE）達到 1479%；而 Ag/(CrMnFeCoNiCu)O/Si 光電感測器於 1050 nm 波長處實現了 6.93 mA/cm2 的光電流密度，響應度為 6.18 A/W，EQE 高達 730%。此外，在 1050 nm 波長範圍內，Ag/(CrMnFeCoNiCu)O/Si 的性能超越了大部分已發表的氧化物光電感測器。該裝置的出色性能歸因於高熵氧化物薄膜中的氧空缺、電子結構與薄膜特性，從而實現了卓越的光吸收和光響應。此外，本研究表明使用溶膠凝膠法製備的HEO材料具有相當優異的潛力，為新一代高性能光電感測器的設計提供了嶄新的思路與方向。

A novel high-entropy oxide (HEO) thin film was synthesized as a light-absorbing layer using the sol-gel method. The sol-gel method offers advantages such as low cost, high uniformity, flexibility in material preparation, and suitability for large-scale production. In this study, uniform and controllable nanostructured thin films were fabricated using a simple process. By combining the unique properties of HEO with the characteristics of thin films, the resulting materials serve as excellent absorbing layers in photodetectors. HEO exhibits exceptional light absorption and photoresponse capabilities. The photoelectric performance of Ag/(CrMnFeCoNi)O/n-Si and Ag/(CrMnFeCoNi)O/n-Si photodetectors was evaluated. Under a bias of 5 V, the Ag/(CrMnFeCoNi)O/Si photodetector achieved a responsivity of up to 12.51 A/W at a wavelength of 590 nm, with an external quantum efficiency (EQE) of 1479%. Meanwhile, the Ag/(CrMnFeCoNiCu)O/Si photodetector demonstrated a significant photocurrent density of 6.93 mA/cm², a responsivity of 6.18 A/W, and an EQE of 730% at a wavelength of 1050 nm. Notably, the performance of Ag/(CrMnFeCoNiCu)O/Si at 1050 nm surpasses that of most reported oxide-based photodetectors. The excellent performance of these devices can be attributed to the oxygen vacancies, electronic structure, and film properties of the high-entropy oxide, which enable outstanding light absorption and responsivity. Furthermore, this study demonstrates that HEO materials prepared via the sol-gel method possess significant potential, providing novel insights and directions for the design of next-generation high-performance photodetectors.

1. Yoo, H., et al., A Review of Phototransistors Using Metal Oxide Semiconductors: Research Progress and Future Directions. Advanced Materials, 2021. 33(47): p. 25.
2. Nguyen, T.X., et al., Advanced High Entropy Perovskite Oxide Electrocatalyst for Oxygen Evolution Reaction. Advanced Functional Materials, 2021. 31(27): p. 10.
3. Wang, T.H., et al., Novel Cu-Mg-Ni-Zn-Mn oxide thin film electrodes for NIR photodetector applications†. Journal of Materials Chemistry C, 2021. 9(14): p. 4961-4970.
4. Petti, L., et al., Metal oxide semiconductor thin-film transistors for flexible electronics. Applied Physics Reviews, 2016. 3(2): p. 53.
5. Ouyang, W.X., et al., Enhancing the Photoelectric Performance of Photodetectors Based on Metal Oxide Semiconductors by Charge-Carrier Engineering. Advanced Functional Materials, 2019. 29(9): p. 20.
6. Yeh, J.W., et al., Nanostructured High‐Entropy Alloys with Multiple Principal Elements: Novel Alloy Design Concepts and Outcomes. Advanced Engineering Materials, 2004. 6(5): p. 299-303.
7. Akrami, S., et al., Defective high-entropy oxide photocatalyst with high activity for CO2 conversion. Applied Catalysis B: Environmental, 2022. 303.
8. Rost, C.M., et al., Entropy-stabilized oxides. Nat Commun, 2015. 6: p. 8485.
9. Sarkar, A., et al., High-Entropy Oxides: Fundamental Aspects and Electrochemical Properties. Adv Mater, 2019. 31(26): p. e1806236.
10. Liu, B., et al., Quasi-metallic high-entropy spinel oxides for full-spectrum solar energy harvesting. Matter, 2024. 7(1): p. 140-157.
11. Qian, L.-X., et al., Ultrahigh-Responsivity, Rapid-Recovery, Solar-Blind Photodetector Based on Highly Nonstoichiometric Amorphous Gallium Oxide. ACS Photonics, 2017. 4(9): p. 2203-2211.
12. Kats, M.A. and F. Capasso, Optical absorbers based on strong interference in ultra‐thin films. Laser & Photonics Reviews, 2016. 10(5): p. 735-749.
13. Dong, R., et al., An Ultraviolet‐to‐NIR Broad Spectral Nanocomposite Photodetector with Gain. Advanced Optical Materials, 2014. 2(6): p. 549-554.
14. Chen, C.Y., et al., Ultra-Broadband High-Entropy Oxide Absorber Layer for Enhanced Photodetector Performance. ACS Appl Mater Interfaces, 2023.
15. Jiang, T., et al., Ga2O3@Al2O3 Core–Shell Nanowires for High-Performance Solar-Blind Photodetectors. ACS Applied Nano Materials, 2023. 6(11): p. 9849-9856.
16. Han-Yin, L., et al., Growing Al2O3by Ultrasonic Spray Pyrolysis for Al2O3/AlGaN/GaN Metal-Insulator-Semiconductor Ultraviolet Photodetectors. IEEE Transactions on Electron Devices, 2014. 61(12): p. 4062-4069.
17. Xu, B., et al., ZnO/Al2O3/p-Si/Al2O3/CuO heterojunction NIR photodetector with inverted-pyramid light-trapping structure. Journal of Alloys and Compounds, 2021. 874.
18. Lee, H.-Y., J.-T. Liu, and C.-T. Lee, Modulated Al2O3-Alloyed Ga2O3Materials and Deep Ultraviolet Photodetectors. IEEE Photonics Technology Letters, 2018. 30(6): p. 549-552.
19. Yıldız, D.E., A. Kocyigit, and M. Yıldırım, Comparison of Al/TiO2/p-Si and Al/ZnO/p-Si photodetectors. Optical Materials, 2023. 145.
20. Young, S.-J., et al., ZnO-Based Ultraviolet Photodetectors With Novel Nanosheet Structures. IEEE Transactions on Nanotechnology, 2014. 13(2): p. 238-244.
21. Hwang, J.-D. and B.-Y. Wu, Using MgO capping layer to enhance the performance of ZnO based metal-semiconductor-metal photodetectors. Sensors and Actuators A: Physical, 2022. 340.
22. Jia, M., et al., Low-power-consumption ultraviolet photodetector based on p-NiO/SiO2/n-ZnO. Optics & Laser Technology, 2023. 157.
23. Fang, L., et al., Broadband ultraviolet photodetector based on rare-earth metal oxide Nd2O3. Journal of Physics D: Applied Physics, 2024. 57(14).
24. Zhang, C., et al., High-performance fully transparent Ga2O3 solar-blind UV photodetector with the embedded indium–tin–oxide electrodes. Materials Today Physics, 2023. 33.
25. Chen, X., S. Huang, and N. Nasiri, Facile Fabrication of UV Photodetectors Using Spin-Coating Flame-Synthesized ZnO Nanoparticles. ACS Applied Nano Materials, 2024. 7(4): p. 3589-3600.
26. Athira, M., S.P. Bharath, and S. Angappane, SnO2-NiO heterojunction based self-powered UV photodetectors. Sensors and Actuators A: Physical, 2022. 340.
27. Morari, V., et al., Spin-Coating and Aerosol Spray Pyrolysis Processed Zn(1-x)Mg(x)O Films for UV Detector Applications. Nanomaterials (Basel), 2022. 12(18).
28. Reddy, B.K., et al., 1D NiO-3D Fe(2)O(3)mixed dimensional heterostructure for fast response flexible broadband photodetector. Nanotechnology, 2022. 33(23).