Photoconductivity and electronic processes in PCDTBT polymer composite with embedded CdSe nanoplatelets

• Published in: Organic electronics Vol. 112; p. 106693
• Main Authors: Saitov, Shamil R., Amasev, Dmitriy V., Aleksandrov, Alexey E., Kazanskii, Andrey G., Saidzhonov, Bedil M., Melnikov, Aleksandr E., Zhang, Guihang, Tameev, Alexey R., Vasiliev, Roman B., Smirnov, Aleksandr M., Mantsevich, Vladimir N.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.01.2023
• Subjects: CdSe nanoplatelets; Hybrid composite; Photoconductive polymer; Photoconductivity; CdSe nanoplatelets; Photoconductivity; Hybrid composite; Photoconductive polymer
• ISSN: 1566-1199; 1878-5530
• DOI: 10.1016/j.orgel.2022.106693

The photoconductivity in thin films of a new composite based on CdSe nanoplatelets (NPLs) and PCDTBT polymer has been studied using photoconductivity temperature dependences, current-voltage and lux-ampere measurements at various temperatures and applied bias. The incorporation of 7 vol% of NPLs into the polymer blend led to an increase in photoconductivity by an order of magnitude compared to the pristine PCDTBT film in the temperature range of 310–360 K and the electric field strength above 200 V cm−1. An analysis of current-voltage characteristics measured at various temperatures demonstrated that the observed increase in the photoconductivity of the composite is due to a change in the transport mechanism of nonequilibrium charge carriers with an increase in their concentration. The observed saturation of photoconductivity with increasing temperature is supposed to occur due to the increase in exciton diffusion length with temperature increasing and limited effective exciton generation area. [Display omitted] •A bulk heterojunction can be created by embedding the CdSe nanoplatelets into the photoconductive PCDTBT matrix.•The embedding nanoplatelets into polymer increases the material photoconductivity by over an order of magnitude.•The photoconductivity enhancement is caused by increase in photogeneration rate related electron and hole separation.•The effect of nanoplatelets on the charge carrier transport was studied.