RESUMEN
Uncontrolled sunlight entering through windows contributes to substantial heating and cooling demands in buildings, which leads to high energy consumption from the buildings. Recently, perovskite smart windows have emerged as innovative energy-saving technologies, offering the potential to adaptively control indoor solar heat gain through their impressive sunlight modulation capabilities. Moreover, harnessing the high-efficiency photovoltaic properties of perovskite materials, these windows have the potential to generate power, thereby realizing more advanced windows with combined light modulation and energy harvesting capabilities. This review summarizes the recent advancements in various chromic perovskite materials for achieving light modulation, focusing on both perovskite structures and underlying switching mechanisms. The discussion also encompasses device engineering strategies for smart windows, including the improvement of their optical and transition performance, durability, combination with electricity generation, and the evaluation of their energy-saving performance in building applications. Furthermore, the challenges and opportunities associated with perovskite smart windows are explicated, aimed at stimulating more academic research and advancing their pragmatic implementation for building energy efficiency and sustainability.
RESUMEN
Ga2O3 is a wide-bandgap semiconductor that has shown great potential for application in solar-blind ultraviolet (UV) photodetectors. However, the responsivity and detectivity of Ga2O3-based self-driven solar-blind UV photodetectors are insufficient for practical applications at present because of the limited separation of photogenerated carriers in the devices. In this work, Hf0.5Zr0.5O2/ß-Ga2O3 heterojunction-based self-driven solar-blind UV photodetectors are constructed by combining ferroelectric Hf0.5Zr0.5O2 (HfZrO2) material with Ga2O3, taking advantage of the ultrawide bandgap of HfZrO2 and the favorable II-type energy band configuration between both. Upon optimization, a HfZrO2/ß-Ga2O3 heterojunction-based UV photodetector with a HfZrO2 layer thickness of 10 nm is shown to provide remarkable responsivity (R = (14.64 ± 0.3) mA/W) and detectivity (D* = (1.58 ± 0.03) × 1012 Jones), which are much superior to those of a single Ga2O3-based device toward 240 nm light illumination. Further, the device performance is adjustable with varying poling states of HfZrO2 and shows substantial enhancement in the upward poling state, benefiting from the constructive coupling of the ferroelectric depolarization electric field in HfZrO2 and the built-in electric field at the HfZrO2/ß-Ga2O3 interface. Under illumination of weak light of 0.19 µW/cm2, the upward poled device shows significantly enhanced R (52.6 mA/W) and D* (5.7 × 1012 Jones) values. The performance of our device surpasses those of most previously reported Ga2O3-based self-driven photodetectors, indicating its great potential in practical applications for sensitive solar-blind UV detection.
