The layer-by-layer assembly of reduced graphene oxide films and their application as solution-gated field-effect transistors

Autor(es)

dos Santos, Fabricio A. ^[1] ; Vieira, Nirton C. S. ^[2] ; Zambianco, Naiara A. ^[1] ; Janegitz, Bruno C. ^[3] ; Zucolotto, Valtencir ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Phys Inst Sao Carlos, Nanomed & Nanotoxicol Grp, CP 369, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Paulo, Inst Sci & Technol, BR-12231280 Sao Jose Dos Campos, SP - Brazil

^[3] Univ Fed Sao Carlos, Dept Nat Sci Math & Educ, BR-13600970 Araras, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Applied Surface Science; v. 543, MAR 30 2021.
• Citações Web of Science: 0

Resumo

In this study, graphene oxide (GO) has been reduced in two different ways for the production of oppositely charged reduced graphene oxide (rGO) sheets. One reduction route consisted of the covalent modification of GO with (3-aminopropyl) triethoxysilane and subsequent chemical reduction to produce positively charged rGO. In the second route employed, GO was reduced in a domestic microwave oven, in which the presence of urea doped the material with nitrogen, increasing its electrical conductivity considerably. Multilayers of oppositely charged rGO were manufactured using the layer-by-layer (LbL) assembly technique. The kinetics and growth of multi layers were monitored by UV-Vis absorption spectroscopy and quartz crystal microbalance. rGO multilayers on the interdigitated gold electrodes originate high conductive films, in which the number of deposited layers controls the conductivity. As a solution-gated field-effect transistor, the devices presented high trans conductance; (90 mu S and 55 mu S for holes and electrons, respectively). Upon modification of the LbL films with papain, used as a biological recognition element, the devices were capable of detecting Cystatin C protein (a chronic renal disease biomarker) in synthetic urine in concentrations as low as 5 ng.mL(-1). Therefore, the proposed transistors proposed here represent interesting alternatives as novel sensors and biosensors platforms. (AU)

• Processo FAPESP: 17/21898-6 - Novos dispositivos condutores para aplicação em sensores e biossensores eletroquímicos
• Beneficiário: Bruno Campos Janegitz
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/07508-3 - Explorando as propriedades elétricas e ópticas de derivados de grafeno para detecção de cianotoxinas
• Beneficiário: Nirton Cristi Silva Vieira
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 17/21097-3 - Interações abelha-agricultura: perspectivas para a utilização sustentável
• Beneficiário: Osmar Malaspina
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático