Repairing Nanoparticle Surface Defects. Issue 44 (26th September 2017)

• Record Type: Journal Article
• Authors: Marino, Emanuele; Kodger, Thomas E.; Crisp, Ryan W.; Timmerman, Dolf; MacArthur, Katherine E.; Heggen, Marc; Schall, Peter
• Is Part Of: Angewandte Chemie international edition. Volume 56:Issue 44(2017)
• Page Start: 13795
• Page End: 13799
• Publication Date: 2017-09-26
• Subjects: ligand exchange -- nanoplatelets -- nanostructures -- quantum dots -- thiostannates; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201705685
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Solar devices based on semiconductor nanoparticles require the use of conductive ligands; however, replacing the native, insulating ligands with conductive metal chalcogenide complexes introduces structural defects within the crystalline nanostructure that act as traps for charge carriers. We utilized atomically thin semiconductor nanoplatelets as a convenient platform for studying, both microscopically and spectroscopically, the development of defects during ligand exchange with the conductive ligands Na4 SnS4 and (NH4 )4 Sn2 S6 . These defects can be repaired via mild chemical or thermal routes, through the addition of L‐type ligands or wet annealing, respectively. This results in a higher‐quality, conductive, colloidally stable nanomaterial that may be used as the active film in optoelectronic devices. Abstract : Solar devices based on semiconductor nanoparticles require the use of conductive ligands; however, the exchange of insulating ligands with conductive metal chalcogenide complexes introduces structural defects that act as traps for charge carriers. CdSe nanoplatelets were used as a model system to show that it is possible to minimize the formation of defects, as well as trigger surface healing, by a judicious choice of mild treatments.