Mesoporous anatase TiO₂ nanomaterials (MATNs) with both large specific surface areas and structural coherence are highly desirable to achieve excellent physicochemical properties for photovoltaic applications, but the existing synthesis methods either need templates or cause pollution. Herein we report a simple, template-free, and green approach to synthesize MATNs consisting of interconnected nanoparticles. The Ti-complex intermediates were first prepared using titanium isopropoxide and acetic acid in a solvothermal reaction, which went through a morphology transformation sequence of nanowires, microspheres, and microflowers with a prolonged reaction time. Then the Ti-complex intermediates were cracked into MATNs under annealing, which were applied in dye-sensitized solar cells (DSSCs) and hole-conductor-free perovskite solar cells (HPSCs). The mesoporous anatase TiO₂ nanowire-based DSSCs achieved a high power conversion efficiency (PCE) up to 7.78% because of both a high dye-adsorption capacity and long charge-transfer channels, while the PCE based on the P25 photoelectrodes is 6.61%. The further application of mesoporous anatase TiO₂ nanowires in HPSCs achieved an improved PCE of 8.52%, compared to 6.78% for cells prepared using the P25 electrodes.

中文翻译：

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一种简便且绿色的合成介孔锐钛矿型TiO ₂纳米材料的高效染料敏化和无空穴导体的钙钛矿太阳能电池

介孔锐钛矿TiO ₂具有大的比表面积和结构相干性的纳米材料（MATN）是非常理想的，以实现用于光伏应用的出色的理化特性，但是现有的合成方法要么需要模板，要么会造成污染。本文中，我们报告了一种简单，无模板的绿色方法来合成由相互连接的纳米粒子组成的MATN。首先在溶剂热反应中使用异丙醇钛和乙酸制备钛复合物中间体，该溶剂复合物经历了纳米线，微球和微花的形态转变序列，并延长了反应时间。然后，将钛络合物中间体在退火条件下裂解成MATN，将其应用于染料敏化太阳能电池（DSSC）和无空穴导体的钙钛矿太阳能电池（HPSC）中。介孔锐钛矿TiO₂种基于纳米线的DSSC由于高的染料吸附能力和长的电荷转移通道而达到了高达7.78％的高功率转换效率（PCE），而基于P25光电电极的PCE为6.61％。中孔锐钛矿型TiO ₂纳米线在HPSC中的进一步应用实现了8.52％的改善的PCE，而使用P25电极制备的电池的PCE为6.78％。