Thomas Alphi Maria, Vuong Van-Hoang, Ippili Swathi, Jella Venkatraju, Yoon Soon-Gil
Department of Materials Science and Engineering, Chungnam National University, Daedeok Science Town, 34134 Daejeon, Republic of Korea.
ACS Appl Mater Interfaces. 2024 Aug 21;16(33):43795-43805. doi: 10.1021/acsami.4c05210. Epub 2024 Aug 8.
Developing self-powered and flexible optoelectronic sensors with high responsivity and speed is crucial for modern applications, motivating continuous efforts to enhance their performance. Flexo-phototronics is a less-explored but promising technique to elevate the performance of optoelectronics. Therefore, this work addresses the potential of utilizing the flexo-phototronic effect to enhance the performance of a flexible and self-powered ultraviolet photodetector (UV PD) based on ZnAl:LDH (layered double hydroxides) nanosheets (Ns)/NiO heterostructure. The vertically oriented ZnAl:LDH Ns are synthesized via a simple method involving the immersion of a sputtered 10% Al-doped ZnO thin film in deionized water at room ambient conditions. The fabricated PD exhibits an impressive response to 365 nm UV light, with high sensitivity in the order of 10. The device's photocurrent and responsivity are significantly enhanced by the flexo-phototronic effect, attributed to the flexoelectric properties of ZnAl:LDH Ns. Specifically, applying an inhomogeneous tensile strain of 2% boosted the device responsivity by 57.1% and improved its operational speed. Furthermore, a working model revealing the altered energy-band structure is demonstrated to elucidate the flexo-phototronic-induced boost in the photoresponse. The PD also demonstrated a sustainable performance under severe bending cycles, underlining the good flexibility of the device. The results presented in this study demonstrate a self-powered and flexible UV PD and provide a viable approach to augment the performance of optoelectronics through the flexo-phototronic effect.
开发具有高响应度和速度的自供电柔性光电传感器对于现代应用至关重要，这促使人们不断努力提高其性能。柔性光电子学是一种探索较少但很有前景的提高光电子器件性能的技术。因此，本工作探讨了利用柔性光电子效应来提高基于ZnAl:LDH（层状双氢氧化物）纳米片（Ns）/NiO异质结构的柔性自供电紫外光电探测器（UV PD）性能的潜力。垂直取向的ZnAl:LDH Ns通过一种简单的方法合成，该方法包括在室温环境条件下将溅射的10% Al掺杂ZnO薄膜浸入去离子水中。所制备的PD对365 nm紫外光表现出令人印象深刻的响应，灵敏度高达10左右。由于ZnAl:LDH Ns的挠曲电特性，柔性光电子效应显著提高了器件的光电流和响应度。具体而言，施加2%的不均匀拉伸应变可使器件响应度提高57.1%，并提高其工作速度。此外，还展示了一个揭示能带结构变化的工作模型，以阐明柔性光电子效应引起的光响应增强。该PD在严重弯曲循环下也表现出可持续的性能，突出了器件良好的柔韧性。本研究结果展示了一种自供电柔性UV PD，并提供了一种通过柔性光电子效应增强光电子器件性能的可行方法。
