Versatile Titanates: Classification, Property, Preparation, and Sustainable Energy Catalysis

Abstract

Global warming, energy deficiency, and environmental deterioration triggered by burning fossil fuels, may severely impair economic development and human life and health. Green solar power, mechanical energy, and temperature fluctuation heat energy abound in nature and are readily accessible. Thanks to various appealing characteristics, titanates are universally employed to harvest these sustainable energy sources to produce renewable fuels through photocatalysis, piezocatalysis, and pyrocatalysis, alleviating above serious issues. In this review, the research progress in energy catalysis driven by solar light, mechanical stress, and temperature fluctuation over titanates is comprehensively described. It starts with the classification and introduction of diverse titanates. Next, the main methods for preparing titanates are introduced. Highlighted are titanates acting as cocatalysts, photocatalysts, piezocatalysts, and pyrocatalysts to participate in water splitting reaction for H 2 evolution and atmospheric CO 2 reduction conversion into CO or hydrocarbons. In particular, the material modification strategies for improving photocatalytic performance are discussed. Finally, the rosy prospects of the future development of energy catalysis application for titanates are looked into.

Exploring 2D Energy Storage Materials: Advances in Structure, Synthesis, Optimization Strategies, and Applications for Monovalent and Multivalent Metal‐Ion Hybrid Capacitors

“…Crystal structures of several typical such TMOs are presented in Figure 4. [64][65][66][67][68] Manganese dioxide (MnO 2 ) has six common crystal structures: hollandite-type MnO 2 (α-MnO 2 ), pyrolusite-type MnO 2 (β-MnO 2 ), nsutite-type MnO 2 (γ-MnO 2 ), birnessite-type MnO 2 (δ-MnO 2 ), hausmannite-type MnO 2 (λ-MnO 2 ), and ramsdellite-type MnO 2 (R-MnO 2 ). [69,70] Among them, the MnO 6 octahedron, in which Mn 4+ is surrounded by six oxygen atoms, is the basic building unit, which can combine into 1D (α-, β-, γ-, and R-MnO 2 ), 2D (δ-MnO 2 ), and 3D (λ-MnO 2 ) tunnel structures by sharing vertices and edges, corresponding to different crystal structures.…”

Fabrication of a lead-free ternary ceramic system for high energy storage applications in dielectric capacitors

“…The developments of the secondary phase indicate the solid solubility limit of Nd 0.33 NbO 3 in the 0.94Bi 0.5 Na 0.5 TiO 3 -0.06BaTiO 3 system of about 2 mol%. Previous studies also demonstrated the appearance of this Bi 2 Ti 2 O 7 secondary phase in Bi 0.5 Na 0.5 TiO 3 -BaTiO 3 -based ceramics (Ding et al, 2022;Lu et al, 2011;Ni et al, 2012;Wang et al, 2022). This secondary phase Bi 2 Ti 2 O 7 appeared due to the vaporization of Bi and Na at elevated temperatures (Xu et al, 2015).…”

Remarkable enhancement of photocatalytic performance in LaCrO3 through a controlled chemical reduction process

“…As reported in the literature, LaCrO 3 is not an efficient photocatalyst because it exhibits intrinsic high charge carrier recombination that severely restricts quantum efficiency, leading to a decrease in HER performance. 46,47 According to our data, creating oxygen vacancies by topotactic reduction favors the separation of electrons from holes, thereby enhancing the photocatalytic HER performance of LaCrO 3 -based materials. This method provides an alternative to the usual doping of A and B sites in perovskite oxide-based materials.…”