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The decomposition mechanism of dyes under the synergistic effect of pyroelectric catalysis and photocatalysis was systematically investigated using a BaTiO3/NiB catalyst in this paper, and the degradation efficiency of BaTiO3/NiB was 97.5% under light and 24 cycles of hot and cold at 25 ~ 65 °C, showing high pyroelectroic catalytic RhB decomposition activity and excellent recoverability. The degradation rate constants of RhB chromophore degradation by Pyro-photocatalytic coupled were 3.2 times as high as those of photocatalysis and 11.8 times as high as those of pyroelectric catalysis. In this study, we used light-assisted electrodeposition to deposit a thin layer of amorphous NiB acid salts onto the surface of a BaTiO3 photoelectrode aiming to explore its influence on photocharge separation and the catalytic mechanism of NiB in the context of pollutant degradation. The synergies between the pyroelectric internal field and the amorphous Ni–B acid salt thin layer during photogenerated charge separation were extensively explored in this paper, including the introduction of a port for pyroelectric polarization. [ABSTRACT FROM AUTHOR]

In this paper, the lithium tantalite ( ${{\rm{LiTaO}}}_{3}$ ) thin film has been employed as the highly sensitive element for infrared detection of compound (refrigerant) gases such as 1,1,1,2-Tetrafluoroethane ( ${{\rm{C}}}_{2}{{\rm{H}}}_{2}{{\rm{F}}}_{4}$ ) and 1,1,1,2,3,3,3-Heptafluoropropane ( ${{\rm{C}}}_{3}{{\rm{F}}}_{7}{\rm{H}}$ ). The ${{\rm{LiTaO}}}_{3}$ thin film was subjected to the mid-infrared light from output transmission spectra of ${{\rm{C}}}_{2}{{\rm{H}}}_{2}{{\rm{F}}}_{4}$ as well as ${{\rm{C}}}_{3}{{\rm{F}}}_{7}{\rm{H}}$ molecules used as sources. The technology for preparation of ${{\rm{LiTaO}}}_{3}$ thin film as well as detector design and manufacturing are presented. Particular attention was paid to production of conductive electrodes, including a very thin semitransparent ${Au}$ layer evaporated on the top surface of ${{\rm{LiTaO}}}_{3}$ pyroelectric material. Important characteristics of the ${{\rm{LiTaO}}}_{3}$ based pyroelectric system are briefly discussed. Additionally, the design, construction, and performance of the gas chamber operating as a channel for gas sensor testing is briefly described. The pyroelectric open-circuit voltage generated in ${{\rm{LiTaO}}}_{3}$ was boosted with a signal processing circuit for selective high-sensitivity detection of compound gases at room temperature. The infrared (IR) filters such as titanium dioxide $({{\rm{TiO}}}_{2}$ ) and zinc oxide $\left({\rm{ZnO}}\right)$ having narrow bandwidth and working at a normal incidence were integrated into a compact and portable pyroelectric micro-sensor before the ${{\rm{LiTaO}}}_{3}$ pyroelectric element in the same package for cleaning background in a broad IR spectrum of both refrigerant gases. The performance, stability, and accuracy of fabricated ${{\rm{LiTaO}}}_{3}$ -based IR gas sensors operating on the pyroelectric open-circuit voltage were tested and improved. IR gas sensors designed and prepared in this study can be utilized for non-contact, sensitive, and selective detection of highly hazardous and explosive gases.

Directly transforming solar energy into chemical compounds via photocatalytic water splitting can continually producing hydrogen, regarded as one of the ultimate sustainable energy sources. The key point of achieving high photoelectrochemical (PEC) water splitting performance depends on the successful design and synthesis of high-efficient photocatalysts. However, the slow separation and fast recombination of photo generated charge carriers greatly limit the utilization of solar energy, resulting in low PEC water splitting efficiency. Recently, piezoelectric/pyroelectric effect assisted PEC water splitting brings new sight on improving charger separate and transfer behaviors. In this review, the recent advancements and state-of-the-art progress in piezoelectric/pyroelectric effect assisted PEC water splitting are summarized and discussed. Different types of photocatalysts are classified according to their chemical constitutions and the corresponding advantages of each type are also discussed. Furthermore, the progress of coupling piezoelectric effect and pyroelectric effect in one PEC water splitting system is also introduced. Finally, the prospects, critical challenges and promising strategies for the application of piezoelectric/pyroelectric materials in PEC water splitting are highlighted., (© 2024 Wiley-VCH GmbH.)

• Pd/BTOH x @NC y with strength-regulated polarized electric field is synthesized. • The electric field is provided by BaTiO 3 and regulated by carbon shell thickness. • Carbon shell promotes charge transfer during FAO and excludes electronic effect. • The optimized electric field strength leads to high FAO catalytic performance. • CO ad is removed by the pyroelectric effect induced by the temperature change. To solve the severe problem of environmental pollution, the demand for commercial applications of direct formic acid fuel cell (DFAFC) has significantly increased. Designing electrocatalysts with high anti-poisoning ability and activity for formic acid electrooxidation (FAO) is the key for the development of DFAFC. Utilizing polarized electric field is a new attempt to improve catalytic performance as it can adjust the adsorption energy of reactants or intermediate species on the catalysts. In this work, pyroelectric material BaTiO 3 (BTOH), which generate polarized electric field, was introduced for FAO for the first time. A series of core–shell structured Pd/BTOH x @NC y catalysts was synthesized with BTOH as the core, nitrogen-doped carbon as the shell, and palladium nanoparticles as the active sites. Among all catalysts, Pd/BTOH 1 @NC 0.5 with the optimal carbon shell thickness of 4.6 nm owns the highest FAO catalytic activity and anti-poisoning ability because the carbon layer regulates the electric field strength to optimize the palladium surface adsorption energy. The study excluded the influence of electronic effect and revealed the effect of polarized electric field strength on the FAO activity and anti-poisoning ability through changing the thickness of carbon shell. In addition, the alternating cold-hot excitation experiments demonstrated that the polarized electric fields can effectively remove the poisoned substance on the surface of palladium. This study guides a new strategy to design electrocatalysts for FAO. [ABSTRACT FROM AUTHOR]

Charge separation and transport as well as light absorption are pivotal in determining the efficiency of dye degradation. Here, we designed a PZT/Ag 2 O heterostructure to improve the degradation of dye by chemical precipitation method. The carrier separation process of Z-scheme heterojunction and the promotion effect of pyroelectric polarization on the performance of PZT/Ag 2 O heterojunction are discussed in detail. Under 20–55 °C temperature cycle and visible light irradiation, PZT/1.5Ag 2 O with bi-catalysis could degrade up to 93.7% of RhB within 140 min. It was 3.38 times and 1.51 times higher than bi-catalysis degradation rate of PZT (27.78%) and Ag 2 O (61.97%) alone, respectively. The improvement of catalytic efficiency is due to the enhanced light response range of the PZT/Ag 2 O heterojunction, while the pyroelectric polarization further promotes carrier separation and transfer. In addition, we found an interesting phenomenon of increased hydrophilicity of the composite, which may also be one of the reasons for its improved performance. The concept of PZT/Ag 2 O heterostructure pyro-photo-catalyst provides an effective way to utilize solar energy and thermal energy. • The Z-scheme heterojunction PZT/Ag 2 O was prepared by the chemical precipitation method. • The pyro-/photo-bi-catalysis based on PZT/Ag 2 O heterojunction was used for degrade dyes. • PZT/Ag 2 O heterojunction enhances the light response range and redox capacity. • The pyroelectric polarization can promote the carrier separation and transfer. • Compared with PZT, PZT/Ag 2 O heterojunction has a large contact area with the dye wastewater. [ABSTRACT FROM AUTHOR]

Highlights: [•] Monocrystalline LiTaO3 thin films with a minimum thickness of 0.4μm were fabricated. [•] Dielectric and pyroelectric properties were studied versus thickness and temperature. [•] The dielectric loss factor is increased with reduction of film thickness. [•] Stoichiometric LiTaO3 shows a lower performance than congruent LiTaO3. [•] Pyroelectric detectors with a performance close to the limit become feasible. [ABSTRACT FROM AUTHOR]

As an application of characteristic of spark plasma sintering (SPS) method, which can produce highly sintered material with almost no change in compositional distribution, sintered materials that consist of different compositions were prepared. Perovskite three component system, xPb(Zn1/3Nb2/3)O3–yPbZrO3–(1−x−y)PbTiO3, exhibits a very sharp pyroelectric peak at phase transition temperature between FRL and FRH phases. When a mixture of calcined materials having different compositions of this system was sintered by SPS, the compositional distribution in the starting mixture was almost maintained. The sintered material exhibited high pyroelectric coefficient over a wide temperature range. [Copyright &y& Elsevier]