Charge Transport in Trap-Sensitized Infrared PbS Quantum-Dot-Based Photoconductors: Pros and Cons
Autor: | Isaac Suárez, Rafael Abargues, Pedro J. Rodríguez-Cantó, Juan P. Martínez-Pastor, Alberto Maulu, Juan Navarro-Arenas, Juan F. Sánchez-Royo |
---|---|
Rok vydání: | 2018 |
Předmět: |
Materials science
Fabrication Infrared doctor blade General Chemical Engineering Optical power 02 engineering and technology 010402 general chemistry 01 natural sciences Article quantum dot solid lcsh:Chemistry Responsivity Photosensitivity PbS QD photodetectors General Materials Science business.industry Nanotecnologia PbS quantum dots Photoconductivity Ciència dels materials 021001 nanoscience & nanotechnology 0104 chemical sciences PbS QD photoconductivity ligand exchange lcsh:QD1-999 Quantum dot Optoelectronics solution processing 0210 nano-technology business Dark current |
Zdroj: | Maulu, Alberto Navarro-Arenas, Juan Rodríguez-Cantó, Pedro J. Sánchez Royo, Juan Francisco Abargues, Rafael Suárez, Isaac Martínez Pastor, Juan Pascual 2018 Charge Transport in Trap-Sensitized Infrared PbS Quantum-Dot-Based Photoconductors: Pros and Cons Nanomaterials 8 9 677-1 677-18 RODERIC. Repositorio Institucional de la Universitat de Valéncia instname Nanomaterials, Vol 8, Iss 9, p 677 (2018) Nanomaterials Volume 8 Issue 9 |
Popis: | 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 (< 1 pW). At medium&ndash high incident optical powers (> 100 pW), where traps are filled, both MPA- and TBAI-treated photodevices exhibit similar behavior, characterized by lower responsivity and faster response time, as limited by the mobility in the QD solid. |
Databáze: | OpenAIRE |
Externí odkaz: |