Composition-dependent photocatalytic activity and high-mobility carrier gas in NaTaO3/BaBiO3 heterojunctions

Author(s)

Portugal, Guilherme Ribeiro ; Ronchi, Rodrigo Mantovani ; Santos, Sydney Ferreira ; Arantes, Jeverson Teodoro

• Document type: Journal article
• Source: SURFACES AND INTERFACES; v. 36, p. 10-pg., 2023-02-01.

Abstract

Perovskite oxide heterostructures have been extensively investigated for their excellent nanoelectronics and photocatalytic properties. Herein, the general features of monoclinic (001) NaTaO3/BaBiO3 heterojunctions are theoretically investigated, exploring how the interface creation affects their physicochemical properties. Density functional theory results reveal that a superlattice with 24 wt.% of BaBiO3 displays a typically desired electronic structure for photocatalytic reactions, with an intermediate band gap and highly dispersive energy levels. Hybrid functional calculations provide a band gap of 1.85 eV, with optical absorption peaks inside the visible light spectrum and band-edge potentials better aligned with water splitting levels when compared with the pristine NaTaO3 phase. Upon increasing the number of BaBiO3 layers a semiconductor-to-metal transition is observed and described based on electrostatic and polarization arguments, leading to the formation of a high-mobility two-dimensional electron gas (2DEG) at the interface. The presented results highlight the importance of such nanojunctions not only for photocatalytic but also for nanoelectronics applications. (AU)

• FAPESP's process: 19/22183-6 - Electrocatalysis VI: fundamental and applied aspects of emerging and classical problems in electrochemical energy conversion
• Grantee: Edson Antonio Ticianelli
• Support Opportunities: Research Projects - Thematic Grants