Driving electrochemical membrane processes with coupled ionic diodes

Autor(es)

Li, Zhongkai ; Mathwig, Klaus ; Arotiba, Omotayo A. ; Tshwenya, Luthando ; Neto, Evaldo Batista Carneiro ; Pereira, Ernesto Chaves ; Marken, Frank

• Tipo de documento: Artigo Científico
• Fonte: CURRENT OPINION IN ELECTROCHEMISTRY; v. 39, p. 8-pg., 2023-04-11.

Resumo

Ionic diodes have emerged repeatedly in the literature for gel interfaces, for nanopores and channels, for nano-/micro-fluidic systems, and for asymmetrically ionomer-covered microholes. Concentration polarisation is likely to be the key to under-standing the diode function and the diode time constant tdiode, i.e. the time for approaching steady state following a potential/ polarity switch. For frequencies higher than udiode = 2pf = (tdiode)-1, the polarization mechanism is too slow for ion cur-rent rectification. Below the frequency associated with the diode time constant, irreversibility in ion flow is induced and the diode switches between two resistive states at opposite po-tentials ("open" and "closed"). The irreversible flow of ions allows energy conversion from electrical to electrochemical. For energy conversion, two coupled ionic diodes are neces-sary driven by alternating current (AC) electricity to minimise driver electrode electrolysis and energy losses. Opportunities for AC-desalination and for electroosmotic water harvesting with coupled ionic diodes are discussed. (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