Omotosho Khalil D, Gurung Vasanta, Banerjee Progna, Shevchenko Elena V, Berman Diana
Materials Science and Engineering Department, University of North Texas, 1155 Union Circle, Denton, TX 76203, USA.
Center for Nanoscale Materials, Argonne National Laboratory, Argonne, IL 60439, USA.
Polymers (Basel). 2024 Jan 23;16(3):308. doi: 10.3390/polym16030308.
Photocatalytic self-cleaning coatings with a high surface area are important for a wide range of applications, including optical coatings, solar panels, mirrors, etc. Here, we designed a highly porous TiO coating with photoinduced self-cleaning characteristics and very high hydrophilicity. This was achieved using the swelling-assisted sequential infiltration synthesis (SIS) of a block copolymer (BCP) template, which was followed by polymer removal via oxidative thermal annealing. The quartz crystal microbalance (QCM) was employed to optimize the infiltration process by estimating the mass of material infiltrated into the polymer template as a function of the number of SIS cycles. This adopted swelling-assisted SIS approach resulted in a smooth uniform TiO film with an interconnected network of pores. The synthesized film exhibited good crystallinity in the anatase phase. The resulting nanoporous TiO coatings were tested for their functional characteristics. Exposure to UV irradiation for 1 h induced an improvement in the hydrophilicity of coatings with wetting angle reducing to unmeasurable values upon contact with water droplets. Furthermore, their self-cleaning characteristics were tested by measuring the photocatalytic degradation of methylene blue (MB). The synthesized porous TiO nanostructures displayed promising photocatalytic activity, demonstrating the degradation of approximately 92% of MB after 180 min under ultraviolet (UV) light irradiation. Thus, the level of performance was comparable to the photoactivity of commercial anatase TiO nanoparticles of the same quantity. Our results highlight a new robust approach for designing hydrophilic self-cleaning coatings with controlled porosity and composition.
具有高表面积的光催化自清洁涂层对于包括光学涂层、太阳能电池板、镜子等在内的广泛应用至关重要。在此，我们设计了一种具有光诱导自清洁特性和极高亲水性的高度多孔TiO涂层。这是通过嵌段共聚物（BCP）模板的溶胀辅助顺序浸润合成（SIS）实现的，随后通过氧化热退火去除聚合物。采用石英晶体微天平（QCM）通过估计作为SIS循环次数函数渗入聚合物模板的材料质量来优化浸润过程。这种采用溶胀辅助SIS的方法产生了具有相互连接的孔网络的光滑均匀TiO薄膜。合成的薄膜在锐钛矿相中表现出良好的结晶度。对所得的纳米多孔TiO涂层进行了功能特性测试。暴露于紫外线照射1小时后，涂层的亲水性得到改善，与水滴接触时润湿角减小到无法测量的值。此外，通过测量亚甲基蓝（MB）的光催化降解来测试它们的自清洁特性。合成的多孔TiO纳米结构显示出有前景的光催化活性，在紫外线（UV）光照射180分钟后，显示出约92%的MB降解。因此，性能水平与相同数量的商业锐钛矿TiO纳米颗粒的光活性相当。我们的结果突出了一种设计具有可控孔隙率和组成的亲水性自清洁涂层的新的稳健方法。
