6533b859fe1ef96bd12b7946

RESEARCH PRODUCT

Charge Transport in Trap-Sensitized Infrared PbS Quantum-Dot-Based Photoconductors: Pros and Cons

Isaac SuárezRafael AbarguesPedro J. Rodríguez-cantóJuan P. Martínez-pastorAlberto MauluJuan Navarro-arenasJuan F. Sánchez-royo

subject

Materials scienceFabricationInfrareddoctor bladeGeneral Chemical EngineeringOptical power02 engineering and technology010402 general chemistry01 natural sciencesArticlequantum dot solidlcsh:ChemistryResponsivityPhotosensitivityPbS QD photodetectorsGeneral Materials Sciencebusiness.industryNanotecnologiaPbS quantum dotsPhotoconductivityCiència dels materials021001 nanoscience & nanotechnology0104 chemical sciencesPbS QD photoconductivityligand exchangelcsh:QD1-999Quantum dotOptoelectronicssolution processing0210 nano-technologybusinessDark current

description

Control of quantum-dot (QD) surface chemistry offers a direct approach for the tuning of charge-carrier dynamics in photoconductors based on strongly coupled QD solids. We investigate the effects of altering the surface chemistry of PbS QDs in such QD solids via ligand exchange using 3-mercaptopropionic acid (MPA) and tetrabutylammonium iodide (TBAI). The roll-to-roll compatible doctor-blade technique was used for the fabrication of the QD solid films as the photoactive component in photoconductors and field-effect phototransistors. The ligand exchange of the QD solid film with MPA yields superior device performance with higher photosensitivity and detectivity, which is due to less dark current and lower noise level as compared to ligand exchange with TBAI. In both cases, the mechanism responsible for photoconductivity is related to trap sensitization of the QD solid, in which traps are responsible of high photoconductive gain values, but slow response times under very low incident optical power (&lt

yearjournalcountryeditionlanguage
2018-08-30
10.3390/nano8090677http://hdl.handle.net/10550/67433