Metal halide perovskites for greener, more sustainable IoTs

Full text: The rapid development of the Internet of Things (IoTs), ranging from smart home appliances to industrial sensors has catalysed an unprecedented demand for reliable, energy-efficient solutions, particularly in indoor environments where conventional power sources may be constrained. Metal halide perovskites, known for remarkable opto-electronic properties, tunable bandgap, and ease of fabrication, have emerged as promising candidates for low-cost, high efficiency indoor photovoltaics. In this talk, I will firstly illustrate our findings on the theoretical maximum efficiencies versus band gap measured for indoor photovoltaic devices under LED light. Specifically, the ideal bandgap for such LED light sources is in the range of 1.7-1.9 eV, with a maximum efficiency of 55% achieved at a bandgap of 1.74 eV. Then, I will demonstrate our recent strategy of using guanidium bromine to reduce non-radiative losses associated with wide bandgap perovskites and their interfaces, enabling the 1.74 eV-perovskite solar cell/module to achieve efficiency of 38.4%/29.9%, respectively, under weak indoor light (warm LED, 1000 lux). Finally, I will discuss Halocell's recent development on roll-to-roll production of perovskite solar module for indoor IoT applications. (author)