Importance of Developing Photovoltaics-Powered Vehicles

The development of photovoltaics (PV)-powered vehicles are expected to contribute to reduce CO2 emission of vehicles and create a clean energy society. This paper presents the impact of high-efficiency solar cell modules on reduction in CO2 emission, charging cost reduction for electric vehicles, and reducing storage capacity of PV-powered electric vehicles. In this paper, the effects of solar cell module efficiency upon driving distance of PV-powered vehicles are also shown. Especially, the potential of Si tandem solar cells for PV-powered vehicle applications is discussed. This paper presents that the III-V/Si 3-junction solar cell modules with an efficiency of more than 37% have the potential of longer driving distance of 30 km/day average and more than 50 km/day on a clear day compared to an average 16 km/day driving by vehicles powered by 20% efficiency Si solar cell modules.

Effects of heterofunctional alkali-metal formate doping on perovskite solar cell performance

Various internal and external defects present in the perovskite film are one of the main factors that causelow efficiency and stability, and in order to realize high-performance perovskite solar cells, it is necessaryto develop a method to effectively suppress them. In this study, a heterofunctional dopants strategy wasattempted to integrate the effect of alkali metal cations (Rbþ and Kþ) and formate anion (HCOO) throughdoping engineering with alkali-metal formates, i.e., rubidium formate (RbHCOO) and potassium formate(KHCOO). Inclusive physical and photoelectric analysis revealed that doping with a small amount ofalkali-metal formate leads to crystal growth and reduction of grain boundaries, and further passivates orinhibits bulk and surface defects. As a result, the photogenerated charge recombination was reduced andthe charge carrier transport was improved, leading to improved PSC performance. RbHCOO-dopedinverted planar PSCs achieved a PCE of up to 20.41% with long-term stability. Our findings provide away for producing high-quality perovskite films with low defect densities that are essential for realizinghigh-performance PSCs.