Possible Charge-Transfer-Induced Conductivity Enhancement in TiO2 Microtubes Decorated with Perovskite CsPbBr3 Nanocrystals

Autor(es)

Gomez, Cynthia Marina ^[1] ; Pan, Shuang ^[2] ; Braga, Helder Moreira ^[1] ; de Oliveira, Leonardo Soares ^[1] ; Dalpian, Gustavo Martini ^[1] ; Biesold-McGee, Gill Vincent ^[2] ; Lin, Zhiqun ^[2] ; Santos, Sydney Ferreira ^[1] ; Souza, Jose Antonio ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed ABC, BR-09210580 Santo Andre, SP - Brazil

^[2] Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 - USA

• Tipo de documento: Artigo Científico
• Fonte: Langmuir; v. 36, n. 19, p. 5408-5416, MAY 19 2020.
• Citações Web of Science: 0

Resumo

Halide perovskite CsPbBr3 quantum dots (QDs) were synthesized via supersaturated recrystallization process and deposited on the surface of TiO2 microtubes forming local nano-heterostructures. Structural, morphological, and optical characterizations confirm the formation of heterostructures comprised of TiO2 microtube decorated with green-emitting CsPbBr3 nanocrystals. Optical characterizations reveal the presence of two band gap energies corresponding to CsPbBr3 (2.34 eV) and rutile-TiO2 (2.97 eV). Time-resolved photoluminescence decays indicate different charge dynamics when comparing both samples, revealing the interaction of CsPbBr3 QDs with the microtube surface and thus confirming the formation of local nano-heterostructures. The voltage-current measurements in the dark show an abrupt decrease in the electrical resistivity of the CsPbBr3/TiO2 heterostructure reaching almost 95% when compared with the pristine TiO2 microtube. This significant increase in the electrical conductivity is associated with charge transfer from perovskite nanocrystals into the semiconductor microtube, which can be used to fine tune its electronic properties. Besides controlling the electrical conductivity, decoration with semiconducting nanocrystals makes the hollow heterostructure photoluminescent, which can be classified as a multifunctionalization in a single device. (AU)

• Processo FAPESP: 17/02317-2 - Interfaces em materiais: propriedades eletrônicas, magnéticas, estruturais e de transporte
• Beneficiário: Adalberto Fazzio
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 15/10900-4 - Síntese e Caracterização de Propriedades Físicas de Materiais com Estruturas Micro/Nano Hierárquicas
• Beneficiário: Cynthia Marina Rivaldo Gómez
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 18/15682-3 - Síntese e caracterização das propriedades físicas de materiais semicondutores micro/nano estruturados
• Beneficiário: José Antonio Souza
• Modalidade de apoio: Auxílio à Pesquisa - Regular