Boosting Charge Mediation in Ferroelectric BaTiO_3−x‐Based Photoanode for Efficient and Stable Photoelectrochemical Water Oxidation

Abstract

Oxygen evolution reaction (OER) is a bottleneck to photoelectrochemical (PEC) water splitting; however, there remains an impressive challenge for intrinsic charge transport for the development of integrated photoanodes. Herein, covalent triazine frameworks as conjugated molecules are grafted on the surfaces of ferroelectric BaTiO3−x (CTF/BTO) nanorod array, and then oxyhydroxide oxygen evolution cocatalyst (OEC) is constructed as an integrated photoanode. The OEC/CTF/BTO array not only achieves a high photocurrent density of 0.83 mA cm−2 at 1.23 V versus reversible hydrogen electrode (vs RHE) and low onset potential of ≈0.23 VRHE, but also optimizes outstanding stability. To disclose the origin, the enhanced PEC activity can be contributed to the integration of CTF and OEC, enhancing light‐harvesting capability, boosting charge carrier mediation, and promoting water oxidation kinetics through electrochemical analysis and density functional theory calculations. This study not only provides an alternative to accelerate charge transfer, but also paves the rational design and fabrication of integrated photoanodes for boosting PEC water splitting performance.

Synthesis and improved photoelectrochemical performances of oxygen-deficient TiO2/black-BaTiO3/CdS multiple-heterojunction nanoarrays

“…O1 1s at 529.18 eV corresponds to the lattice oxygen in a perovskite environment of BaTiO 3 , and O2 1s at 531.38 eV may be the adsorbed oxygen on the sample surface, as reported previously by Li et al 25 The slight decrease in lattice oxygen after the blackening process can be attributed to the formation of oxygen vacancies. 37 The C 1s references were used as usual, as shown in Fig. 3d.…”

Cobalt site coordinated polyterthiophene derivant/hematite hybrid photoanode for light-driven water oxidation

“…17 Thin layers of polymer-coating heterojunction photoelectrodes have been reported to exhibit improved photocurrent densities and enhanced stability. 5,18,19 Polyterthiophene (abbreviated as PTTh), in particular, has been extensively studied in PEC systems, for its potential to form a heterojunction with hematite to promote charge separation and transportation. 20,21 However, a signicant limitation of these polymers is their inability to provide efficient catalytic sites for water oxidation.…”