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Hydrogen peroxide (H2O2) plays a pivotal role in multiple industries, spanning healthcare, energy, chemical synthesis, and environmental protection, yet achieving its safe, ecofriendly, simple, and efficient production under ambient conditions remains challenging. In contrast to traditional piezoelectric and photocatalysis techniques, tribocatalysis has recently attracted attention owing to its mild requirements and low energy consumption. Thus, in this study, we synthesized BaxSr1–xNb2O6 (x = 0.4, 0.5, 0.6, 0.7) (BSN) ferroelectric nanopowders via solid-phase synthesis and high-energy ball milling to investigate the impact of BSN tribocatalysis on H2O2 production. Our findings reveal that H2O2 can be efficiently synthesized through a tribocatalysis pathway at room temperature and normal pressure by exerting mechanical force during physical contact between BSN particles and deionized water/O2 interfaces. This interaction induces electron transfer, leading to the generation of reactive free radicals (•OH and •O2–). Subsequently, these free radicals combine to form H2O2 (2•OH → H2O2, •O2– + e– + 2H+ → 2H2O2). Our results demonstrate that strong ferroelectric properties can enhance the catalytic capability for H2O2 production. Furthermore, the efficiency can be significantly enhanced by facilitating the passage of O2 and incorporating a sacrificial agent, resulting in a high production rate up to 952.65 μmol L–1 h–1. This study presents a new and efficient method for preparing hydrogen peroxide. [ABSTRACT FROM AUTHOR]

This paper reports a novel lead-free tungsten bronze type ceramic, Sr5BiTi3Nb7O30, prepared by a conventional high-temperature solid-state reaction route. The crystal structure identified using synchrotron x-ray diffraction data and Raman spectroscopy for Sr5BiTi3Nb7O30 could be described as an average structure with the centrosymmetric space group P4/mbm and a local non-centrosymmetric structure at room temperature. In the second-harmonic generation measurement, the Sr5BiTi3Nb7O30 compound exhibits second-order nonlinear optical behavior, which suggests the material is ferroelectric. Temperature dependence of the dielectric permittivity indicates that the dielectric anomaly in Sr5BiTi3Nb7O30, associated with the disorder on the A and B sites, results in strong frequency dispersion with a low phase-transition temperature. A macroscopic and phenomenological statistical model was employed to describe the temperature dependence of the dielectric responses of Sr5BiTi3Nb7O30 and Sr6Ti2Nb8O30. The calculated sizes of polar nanoregions for both compounds imply structural disorder induced by A and B sites, giving rise to a more diffuse ferroelectric transition for Sr5BiTi3Nb7O30. The smaller polar nanoregions with smaller electrical dipole moments can be activated at lower temperatures, leading to Sr5BiTi3Nb7O30 having a lower Tm (∼260 K) than other tungsten bronze type ferroelectrics. This work charts a promising feasible route to the development of improved relaxor ferroelectrics in tungsten bronze type oxides. [ABSTRACT FROM AUTHOR]

The tungsten bronze ceramics were prepared by solid-state reaction method to investigate the effect of La3+ concentration on the microstructure, dielectric and ferroelectric properties of Sr4 − xNa2 − xLaxTa0.6Nb9.4O30 (SNLTN: 0 ≤ x ≤ 0.4). X-ray diffraction results show that the tungsten bronze phase structure was a tetragonal phase in the P4bm space group at room temperature. The A-site structural vacancies increases as the structure transformed from “filled” to “unfilled” state. At the same time, the distortion of the BO6 octahedral increases. The results of the temperature dependence of the dielectric constant indicate that adding La3+ promotes the emergence of dipole-glass-like behavior and enhances dielectric relaxation. To better understand how polar clusters in Sr4 − xNa2 − xLaxTa0.6Nb9.4O30 ceramics change with increasing x, the size and kinetic behavior of PNRs were calculated and analyzed using the Vogel-Fulcher relationship and macroscopic and phenomenological statistical model, which reveals that the thermal stability of the dielectric constant is inversely related to the size of PNRs in addition to the long-range ordering of the system is disrupted. Hence, it is critical for the energy storage performance to obtain small size and the high number of active PNRs and the weak coupling between PNRs and other polar clusters. Finally, an energy storage density of 2.06 J/cm3 was received in Sr3.8Na1.8La0.2Ta0.6Nb9.4O30. [ABSTRACT FROM AUTHOR]