Copper vanadates: Targeted synthesis of two pure phases and use in a photoanode/cathode setup for selective photoelectrochemical conversion of carbon dioxide to liquid fuel

Author(s)

Oliveira, Jessica A. A. ; Silva, Roberta R. M. A. ; da Silva, Gelson T. S. T. ; Torres, Juliana A. ; Vali, Abbas ; Ribeiro, Caue ; Rajeshwar, Krishnan ; Ruotolo, Luis A. M.

• Document type: Journal article
• Source: Materials Research Bulletin; v. 149, p. 10-pg., 2022-05-01.

Abstract

Durable photocathodes are a matter of crucial concern in photoelectrochemical (PEC) CO2 reduction and a photoanode/dark cathode configuration is a viable strategy to circumvent this stability issue. In this vein, this study addresses a literature gap related to emerging photoelectrode materials for solar fuels generation. First is the perennial problem of securing a pure phase in the ternary copper vanadate (Cu-V-O) family of inorganic semiconductors. An optimized synthesis route was developed to prepare two copper vanadates with distinct morphological and optical properties. The copper site valence in the precursor influenced the semiconductor composition type: a Cu(II) source led to n-type beta-Cu2V2O7 while employing a Cu(I) source and an inert, deoxygenated environment, p-type alpha-CuVO3 was obtained. The alpha-CuVO3 photoelectrode was unstable and easily converted to beta-Cu2V2O7. Therefore, only the PEC performance of beta-Cu2V2O7 towards CO2 reduction was evaluated in this study, demonstrating that mainly methanol (generation flux: similar to 236 mu mol cm(-2) h(-1)) was selectively formed. (AU)

• FAPESP's process: 16/21515-7 - Development of magnesium oxide with zinc and titanium heterostructure for application in artificial photosynthesis processes
• Grantee: Juliana Arriel Torres
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 20/12706-9 - Development of electrochemical cell for capacitive deionization
• Grantee: Luis Augusto Martins Ruotolo
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/21496-0 - Photoelectrochemical system design for CO2 and CH4 conversion to valuable products
• Grantee: Jéssica Ariane de Oliveira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/01258-5 - Novel chemical catalytic and photocatalytic processes for the direct conversion of methane and CO2 to products
• Grantee: José Maria Correa Bueno
• Support Opportunities: Research Projects - Thematic Grants