Optoelectronic Properties of MAPbI3 Perovskite/Titanium Dioxide Heterostructures on Porous Silicon Substrates for Cyan Sensor Applications

This work elucidates the optoelectronic properties of graphene/methylammonium lead iodide (MAPbI 3 )/titanium dioxide (TiO 2 )/porous Si heterostructure diodes. The porous silicon substrates can accommodate more MAPbI 3 /TiO 2 than the polished silicon substrate such that the MAPbI 3 /TiO 2 /porous Si substrate heterostructures have better optoelectronic properties. Photocurrents from 300 to 900 nm were measured. The photocurrent is high in two ranges of wavelength, which are 300–460 nm and 520–800 nm. The photocurrent plateau covers all visible light (360 to 780 nm) except for cyan between 460 and 520 nm. Therefore, the graphene/MAPbI 3 /TiO 2 /porous Si heterostructure can be utilized as cyan sensors.