Alsulami Qana A, Arshad Zafar, Ali Mumtaz, Wageh S
Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
School of Engineering and Technology, National Textile University, Faisalabad 37640, Pakistan.
Gels. 2023 Jan 24;9(2):101. doi: 10.3390/gels9020101.
The efficient electron transport layer (ETL) plays a critical role in the performance of perovskites solar cells (PSCs). Ideally, an unobstructed network with smooth channels for electron flow is required, which is lacking in the pristine TiO-based ETL. As a potential solution, here we tuned the structure of TiO via optimized heteroatom doping of Al. Different concentrations (1, 2, and 3 wt%) of Al were doped in TiO and were successfully applied as an ETL in PSC using spin coating. A significant difference in the structural, opto-electronic, chemical, and electrical characteristics was observed in Al-doped TiO structures. The opto-electronic properties revealed that Al doping shifted the absorption spectra toward the visible range. Pure titania possesses a bandgap of 3.38 eV; however, after 1, 2, and 3% Al doping, the bandgap was linearly reduced to 3.29, 3.25, and 3.18 eV, respectively. In addition, higher light transmission was observed for Al-doped TiO, which was due to the scattering effects of the interconnected porous morphology of doped-TiO. Al-doped titania shows higher thermal stability and a 28% lower weight loss and can be operated at higher temperatures compared to undoped titania (weight loss 30%) due to the formation of stable states after Al doping. In addition, Al-doped TiO showed significantly high conductivity, which provides smooth paths for electron transport. Thanks to the effective tuning of band structure and morphology of Al-doped TiO, a significant improvement in current densities, fill factor, and efficiency was observed in PSCs. The combined effect of better Jsc and FF renders higher efficiencies in Al-doped TiO, as 1, 2, and 3% Al-doped TiO showed 12.5, 14.1, and 13.6% efficiency, respectively. Compared to undoped TiO with an efficiency of 10.3%, the optimized 2% Al doping increased the efficiency up to 14.1%. In addition, Al-doped TiO also showed improvements in antibacterial effects, required for photoactive textiles.
高效电子传输层（ETL）在钙钛矿太阳能电池（PSC）的性能中起着关键作用。理想情况下，需要一个具有光滑电子流动通道的畅通网络，而原始的TiO基ETL缺乏这一点。作为一种潜在的解决方案，我们在此通过对Al进行优化的杂原子掺杂来调整TiO的结构。将不同浓度（1%、2%和3%重量）的Al掺杂到TiO中，并通过旋涂成功地将其用作PSC中的ETL。在Al掺杂的TiO结构中观察到结构、光电、化学和电学特性存在显著差异。光电特性表明，Al掺杂使吸收光谱向可见光范围移动。纯二氧化钛的带隙为3.38 eV；然而，在1%、2%和3%的Al掺杂后，带隙分别线性降低至3.29、3.25和3.18 eV。此外，Al掺杂的TiO具有更高的光透射率，这是由于掺杂TiO的相互连接的多孔形态的散射效应。Al掺杂的二氧化钛显示出更高的热稳定性，重量损失降低28%，并且由于Al掺杂后形成稳定状态，与未掺杂的二氧化钛（重量损失30%）相比，可以在更高的温度下运行。此外，Al掺杂的TiO显示出显著的高导电性，这为电子传输提供了光滑的路径。由于对Al掺杂TiO的能带结构和形态进行了有效调整，在PSC中观察到电流密度、填充因子和效率有显著提高。更好的短路电流密度（Jsc）和填充因子（FF）的综合作用使Al掺杂的TiO具有更高的效率，因为1%、2%和3%的Al掺杂TiO的效率分别为12.5%、14.1%和13.6%。与效率为10.3%的未掺杂TiO相比，优化后的2%Al掺杂使效率提高到14.1%。此外，Al掺杂的TiO在光活性纺织品所需的抗菌效果方面也有改善。
