Al2SiO5N阻挡层厚度对全固态电致变色器件性能的影响

Impact of Al2SiO5N Barrier Layer Thickness on Performance of All-Solid-State Electrochromic Devices

摘要:

为解决全固态电致变色器件中LiNbO₃电解质层漏电问题，以Al₂SiO₅N作为阻挡层，利用其优异的介电性能，改善器件的综合性能。采用磁控溅射法，以99.95%纯度的Al₂SiO₅作为靶材，在射频功率为150 W、气压为1.5 Pa条件下，在纯氮气氛中制备了Al₂SiO₅N薄膜。采用XRD、SEM和AFM对Al₂SiO₅薄膜微观结构及表面形貌进行表征，通过循环伏安法及结合紫外-可见光谱对ITO/WO₃/Al₂SiO₅N/LiNbO₃/Al₂SiO₅N/NiO_x/ITO器件进行电致变色性能测试，系统地研究了Al₂SiO₅N薄膜层厚度对该器件光电性能的影响及其作用机制。结果表明，随着沉积时间的延长，Al₂SiO₅薄膜的厚度增加，致密性逐渐提高，纳米团簇趋于均匀并呈现小岛状结构。Al₂SiO₅薄膜作为电致变色器件的阻挡层，可明显改善器件的漏电现象。当Al₂SiO₅N层的厚度为90 nm时，全固态电致变色器件的电流密度从无阻挡层时的300.83 μA?cm^-2降至15.70 μA?cm^-2，有效地抑制了漏电现象。同时，器件最大光调制率为52.31%，着色时间为9 s，脱色时间为4 s，最大着色效率为60.67 cm²?C^-1。通过优化Al₂SiO₅N阻挡层与其他功能层之间的界面匹配性，揭示了Al₂SiO₅N层对电致变色器件光电性能的提升作用，为开发高性能无机固态电致变色器件提供了新思路。

Abstract:

To address the leakage issues in LiNbO₃ electrolyte layer of all-solid-state electrochromic devices， Al₂SiO₅N was used as a barrier layer due to its dielectric properties， aiming to enhance the overall device performance. Utilizing the magnetron sputtering method， an electronic barrier layer was incorporated into traditional solid-state devices， resulting in the fabrication of ITO/WO₃/Al₂SiO₅N/LiNbO₃/Al₂SiO₅N/NiO_x/ITO structures. This study investigates the impact of Al₂SiO₅N barrier layer thickness on the photoelectric performance and underlying mechanisms of the devices. The microstructure and surface morphology of the films were characterized using XRD， SEM and AFM， while electrochromic properties were evaluated through cyclic voltammetry and UV-VIS spectroscopy. Results indicate that as the deposition time increases， the Al₂SiO₅N film becomes thicker and denser， with nanoclusters becoming more uniform and adopting a small-island structure. The introduction of barrier layer significantly mitigates leakage currents within the device. Specifically， when the thickness of the Al₂SiO₅N layer is 90 nm， the current density of the all-solid-state electrochromic device decreases from 300.83 μA?cm^-2 （without the barrier layer） to 15.70 μA?cm^-2. This reduction is attributed to the minimized gaps between nanoclusters in the Al₂SiO₅N layer， facilitating ion transport during coloring and fading processes. In conclusion， the optimized all-solid electrochromic device exhibits a maximum optical modulation rate of 52.31%， a coloring time of 9 s， a decolorization time is 4 s， and a maximum coloring efficiency of 60.67 cm²?C^-1. The addition of the Al₂SiO₅N barrier layer effectively enhances the photoelectric performance of the device.