CdS-Decorated Al-Doped ZnO Nanorod/Polymer Schottky Junction Ultraviolet-Visible Dual-Wavelength Photodetector

Ultraviolet and visible dual-wavelength photo sensing was observed using inorganic-organic Schottky junction. Photodetectors were fabricated by depositing dimethyl sulfoxide-modified poly(3,4-ethylenedioxythiophene) poly (styrene sulfonate) conducting polymer on CdS-decorated Al-doped ZnO nanorod arrays. A prominent dual-wavelength photosensitivity was observed at lambda approximate to 380 nm and lambda approximate to 500 nm with fast response and recovery time (similar to 20 ms) even at zero external bias. The maximum device performance was obtained at -5.0 V external bias with external quantum efficiency approximate to 55 864% and similar to 12 590%; responsivity (RA) 171 and 50 A/W; detectivity (D-lambda) approximate to 2.6 X 10(11) and 7.7 X 10(10) jones, corresponding to the wavelengths similar to 380 and 500 nm, respectively. To protect from ambient atmosphere and moisture environment, the device was sealed with polydimethylsiloxane (PDMS) polymer. PDMS-encapsulated device demonstrated excellent photosensing behavior under water environment.