Water-soluble CdTe quantum dots as an anode interlayer for solution-processed near infrared polymer photodetectors

Water-soluble cadmium telluride (CdTe) quantum dots (QDs) used as an anode interlayer in solution-processed near infrared (NIR) polymer photodetectors (PDs) were demonstrated. Polymer PDs incorporated with CdTe QDs as an anode interlayer exhibited 10-fold suppressed dark current density and analogous photocurrent density relative to poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), which resulted in enhanced detectivities over 10(11) Jones in the spectral range from 350 nm to 900 nm. Moreover, with the substitution of PEDOT: PSS by CdTe QDs, the stability of unencapsulated NIR polymer PDs was extended up to 650 hours, which is more than 3 times longer than those with PEDOT:PSS as an anode interlayer. These results indicated that CdTe QDs can be utilized as a solution-processable alternative to PEDOT: PSS as an anode interlayer for high performance NIR polymer PDs.