Understanding Transient Ionic Diode Currents and Impedance Responses for Aquivion-Coated Microholes

Autor(es)

Carneiro-Neto, Evaldo Batista ; Li, Zhongkai ; Pereira, Ernesto ; Mathwig, Klaus ; Fletcher, Philip J. J. ; Marken, Frank

• Tipo de documento: Artigo Científico
• Fonte: ACS APPLIED MATERIALS & INTERFACES; v. N/A, p. 10-pg., 2023-08-11.

Resumo

Ionic diode based devices or circuits can be applied,for example,in electroosmotic pumps or in desalination processes. Aquivion ionomercoated asymmetrically over a Teflon film (5 & mu;m thickness) witha laser-drilled microhole (approximately 10 & mu;m diameter) givesa cationic diode with a rectification ratio of typically 10-20(measured in 0.01 M NaCl with & PLUSMN;0.3 V applied bias). Steady statevoltammetry, chronoamperometry, and electrochemical impedance spectroscopydata are employed to characterize the ionic diode performance parameters.Next, a COMSOL 6.0 finite element model is employed to quantitativelyassess/compare transient phenomena and to extract mechanistic informationby comparison with experimental data. The experimental diode timeconstant and diode switching process associated with a distorted semicircle(with a typical diode switching frequency of 10 Hz) in the Nyquistplot are reproduced by computer simulation and rationalized in termsof microhole diffusion-migration times. Fundamental understandingand modeling of the ionic diode switching process can be exploitedin the rational/optimized design of new improved devices. (AU)

• Processo FAPESP: 21/03592-2 - Modelagem e simulação de dispositivos eletroquímicos por elementos finitos
• Beneficiário: Evaldo Batista Carneiro Neto
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 22/06229-9 - Transporte eletroosmótico retificado de fármacos
• Beneficiário: Evaldo Batista Carneiro Neto
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado