Highly efficient quasi-cubic structured perovskite for harvesting energy from artificial indoor LED light source

•The incorporation of FA+ in MAPbI3 induces a transition in crystal structure from tetragonal to intermediate quasi-cubic.•Quasi-cubic perovskite structured perovskite resulting in more stable and efficient morphology.•The quasi-cubic i-PPVs showed a PCE of 34.07% in comparison to tetragonal structured MAPbI3 (28.63%) under indoor LED lamp at 1000 lx.•The optimized photovoltaic device has displayed lower hysteresis and reduced recombination losses.