PdPt-TiO2 nanowires: correlating composition, electronic effects and O-vacancies with activities towards water splitting and oxygen reduction

Author(s)

da Silva, Anderson G. M. ^{[1, 2]} ; Fernandes, Cibele G. ^[1] ; Hood, Zachary D. ^{[3, 4]} ; Peng, Rui ^[3] ; Wu, Zili ^[3] ; Dourado, Andre H. B. ^[1] ; Parreira, Luanna S. ^[1] ; de Oliveira, Daniela C. ^[5] ; Camargo, Pedro H. C. ^[6] ; Cordoba de Torresi, I, Susana

Affiliation

^[1] I, Univ Sao Paulo, Dept Quim Fundamental, Inst Quim, Av Prof Lineu Prestes 748, BR-05508000 Sao Paulo, SP - Brazil

^[2] Pontificia Univ Catolica Rio de Janeiro PUC Rio, Dept Engn Quim & Mat DEQM, Rua Marques Sao Vicente, 225 Gavea, BR-22453900 Rio De Janeiro, RJ - Brazil

^[3] Oak Ridge Natl Lab, Ctr Nanophase Mat Sci, Oak Ridge, TN 37831 - USA

^[4] Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 - USA

^[5] Ctr Nacl Pesquisa Energia & Mat, Lab Nacl Luz Sincrotron, BR-13083970 Campinas, SP - Brazil

^[6] Univ Helsinki, Dept Chem, AI Virtasen Aukio 1, Helsinki 00014 - Finland

• Document type: Journal article
• Source: APPLIED CATALYSIS B-ENVIRONMENTAL; v. 277, NOV 15 2020.
• Web of Science Citations: 0

Abstract

We report the optimization of both the support and the active phase of PdPt NPs supported on TiO2 nanowires to obtain highly active electro/photocatalysts for the oxygen reduction and water splitting reactions. This system displayed strong metal-support interactions, high concentration of oxygen vacancies, and PdPt NP were similar to 2 nm in size. By optimizing the loading of PdPt, both the photo- and electrocatalytic activities were improved compared to commercial materials. Interestingly, a volcano plot was obtained from the activity and the PdPt composition, and the Pd0.22P0.78-TiO2/C sample afforded the optimal performance. For instance, the amount of hydrogen produced from water splitting was 11.6 mmol/g(catalyst). For the ORR, the activity was similar to a commercial Pt catalyst, but a lower E-onset (0.87 V-RHE vs w 0.95 V-RHE) was detected. The variations in the activities with the composition correlated well with the variations in the electronic effects and the concentration of oxygen vacancies. (AU)

• FAPESP's process: 15/26308-7 - Optimization of the physicochemical properties of nano -structured materials for applications in molecular recognition, catalysis and energy conversion/storage
• Grantee: Roberto Manuel Torresi
• Support type: Research Projects - Thematic Grants
• FAPESP's process: 17/12407-9 - Hybrid nanostructures of transition metal oxides and conducting polymers for various applications
• Grantee: Anderson Gabriel Marques da Silva
• Support type: Scholarships in Brazil - Post-Doctorate
• FAPESP's process: 18/25567-7 - Plasmonic electrocatalysis: investigating shape-dependent charge transfer processes in Cu2O-Au nanocrystals
• Grantee: Anderson Gabriel Marques da Silva
• Support type: Scholarships abroad - Research Internship - Post-doctor