Kim Tea-Yon, Kim Byung Su, Oh Jong Gyu, Park Seul Chan, Jang Jaeyoung, Hamann Thomas W, Kang Young Soo, Bang Jin Ho, Giménez Sixto, Kang Yong Soo
Department of Chemistry, Michigan State University, East Lansing, Michigan 48824-1322, United States.
Department of Energy Engineering and Center for Next Generation Dye-Sensitized Solar Cells, Hanyang University, Seoul 04763, Korea.
ACS Appl Mater Interfaces. 2021 Feb 10;13(5):6208-6218. doi: 10.1021/acsami.0c19352. Epub 2021 Feb 1.
Metal oxide semiconductor/chalcogenide quantum dot (QD) heterostructured photoanodes show photocurrent densities >30 mA/cm with ZnO, approaching the theoretical limits in photovoltaic (PV) cells. However, comparative performance has not been achieved with TiO. Here, we applied a TiO(B) surface passivation layer (SPL) on TiO/QD (PbS and CdS) and achieved a photocurrent density of 34.59 mA/cm under AM 1.5G illumination for PV cells, the highest recorded to date. The SPL improves electron conductivity by increasing the density of surface states, facilitating multiple trapping/detrapping transport, and increasing the coordination number of TiO nanoparticles. This, along with impeded electron recombination, led to enhanced collection efficiency, which is a major factor for performance. Furthermore, SPL-treated TiO/QD photoanodes were successfully exploited in photoelectrochemical water splitting cells, showing an excellent photocurrent density of 14.43 mA/cm at 0.82 V versus the Reversible Hydrogen Electrode (RHE). These results suggest a new promising strategy for the development of high-performance photoelectrochemical devices.
金属氧化物半导体/硫族化物量子点（QD）异质结构光阳极在与氧化锌结合时表现出大于30 mA/cm²的光电流密度，接近光伏（PV）电池的理论极限。然而，二氧化钛却未实现与之相当的性能。在此，我们在二氧化钛/量子点（硫化铅和硫化镉）上应用了一层TiO(B)表面钝化层（SPL），在AM 1.5G光照条件下，光伏电池实现了34.59 mA/cm²的光电流密度，这是迄今为止记录到的最高值。该表面钝化层通过增加表面态密度、促进多重俘获/脱俘获传输以及增加二氧化钛纳米颗粒的配位数来提高电子传导率。这一点，再加上受阻的电子复合，导致了收集效率的提高，而收集效率是性能的一个主要因素。此外，经表面钝化层处理的二氧化钛/量子点光阳极成功应用于光电化学水分解电池，在相对于可逆氢电极（RHE）为0.82 V时显示出14.43 mA/cm²的优异光电流密度。这些结果为高性能光电化学器件的开发提出了一种新的有前景的策略。
