A hybrid photodiode with planar heterojunction structure consisting of ZnO nanoparticles and CuPc thin film

A photodiode with planar heterojunction was fabricated using copper (II) phthalocyanine (CuPc) organic semiconductor and zinc oxide (ZnO) inorganic nanoparticles (NPs, ∼5 nm). The current–voltage (I–V) characteristics of ITO/ZnO NPs/CuPc/Ag device in dark and under illumination with a solar simulator were investigated in detail. The measurement results showed that the device exhibited good rectifying behavior in dark and under illumination. A rectification ratio (RR) of 15.44 at 1.95 V was achieved for the device under 100 mW/cm2 illumination power. Also, the RR of the device as a function of light intensity was observed. The photoresponsive mechanism of the photodiode was illuminated in term of its energy band diagram.

► 5 nm ZnO nanoparticles with polycrystalline were synthesized.
► A photodiode based on ZnO NPs and CuPc was fabricated.
► The photodiode showed high rectifying ratio in dark and under illumination.