Inorganic Perovskites and Organic-Inorganic Halide Perovskites for Solar Cell Applications
ABSTRACT :
Solar energy is unarguably the best option to replace fossil fuels in future. Photovoltaic is a process that converts solar energy to electrical energy. Different kinds of solar cells like Si solar cell, CdTe solar cell, CIGS solar cell, dye sensitized solar cell, quantum dot solar cell, perovskite solar cell have evolved in the past few decades. Among allthe solar cells, organic-inorganic perovskite solar cells have shown tremendous increase in photoconversion efficiency(up to ~ 20 %) with in few years. Recent efforts aremainly focused on developing stable inorganic perovksite materials in order to address the poor stability of organic-inorganic halide perovksites. Inorganic ferroelectric perovksite are other interesting material for solar cell application. The unique ferroelectric property inthese compounds could beused to get large photovoltage. All inorganic ferroelectric perovskite oxides have a bandgap (Eg) > 3 eV except BiFeO3 (Eg = 2.5eV).Tuning the bandgap to ~ 1.5 eV is also another challenging problem. Many studies on photovoltaic and photocurrent properties are being pursued on BiFeO3bulk, thin films and single crystal forms in the last few years. However its poor photoconversion efficiency with very low short circuit current is due to low absorption coefficientand high resistivity. I will present an overview of the above topics in this presentation. Then I will present the preliminary studies I have carried out on understanding the influence of morphology on photoconductivity of spark plasma sintered BiFeO3 pellets. I will propose my research work that will mainly address the methodologies to improve the stability, develop new compounds or hybrid structures for stable solar cell with efficiency over 20 %.