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The design and development of efficient nitride photocatalysts have attracted much attention. Herein, two-dimensional mesoporous Ta 3 N 5 is successfully synthesized through a simple sol-gel process with filter paper as a biological template and a combination of vacuum nitriding reactions. The prepared Ta 3 N 5 shows a wide light response range up to the near infrared (NIR) region due to the nitrogen vacancies generated from substitution of N3− for O2− ions during vacuum nitridation. Significantly, such a narrow bandgap (∼1.99 eV) still satisfies the redox potential of water splitting in thermodynamics. The experimental results show that the Ta 3 N 5 photocatalyst exhibits an enhanced hydrogen production rate of 34.6 μmol h−1 g−1, which is 3.9 and 2.1 times higher than that of Ta 2 O 5 and partial nitridation of Ta 2 O 5 (N–Ta 2 O 5), respectively. This enhanced photocatalytic performance could be attributed to the high specific surface area to provide reactive active sites, substitution of N3− for O2− ions to optimize the band structure, and special two-dimensional mesoporous structure to shorten the charge transfer distance. This work provides a new perspective for the preparation of two-dimensional nitride materials by a biological template method combining vacuum nitriding with enhanced photocatalytic performance. Two-dimensional mesoporous Ta 3 N 5 is synthesized by a simple sol-gel process with filter paper as a biological template and vacuum nitriding reaction, leading to an efficient photocatalytic performance. [Display omitted] • Two-dimensional mesoporous Ta 3 N 5 was prepared by a biological template. • The prepared Ta 3 N 5 shows a wide light response range up to the near infrared region. • The special two-dimensional structure shortens the charge transfer distance. • The Ta 3 N 5 photocatalyst shows a superior hydrogen production performance. [ABSTRACT FROM AUTHOR]

The demand for susceptible and selective hydrogen gas sensors is growing in fuel cells, chemical production, and automotive industries. Detecting H 2 gas at the ppm or ppb level is crucial due to its colourless, odourless, tasteless nature, as well as its flammability and explosiveness. Transition metal dichalcogenides (TMDs) and metal oxide (MO) semiconductors-based hybrid structures have garnered attention in recent years as promising candidates for gas sensing applications owing to their unique properties, including a high surface area, tunable bandgap, and strong gas adsorption. This paper aims to offer insights into the potential of TMD-MO hybrid structures as the next generation of hydrogen gas sensing platforms, contributing to developing highly sensitive and selective gas sensors for diverse industrial applications. TMD-MO hybrid structures are vital for detecting hydrogen gas with high sensitivity and selectivity, which are essential for safe and efficient hydrogen-based systems. Furthermore, these hybrid structures hold significant potential for further customization and enhancement to suit specific applications. Overall, TMD-MO hybrid structures offer a promising avenue for developing next-generation hydrogen gas sensors useable in various industrial applications and promoting a safe and sustainable hydrogen economy. [ABSTRACT FROM AUTHOR]

Photocatalytic technology is the recent investigation focus because of the wide applications in sewage disposal and new energy generation. In this paper, the optical and photocatalytic properties of TiO 2 NTAs were enhanced by the hydrothermal deposition of CuBi 2 O 4 by regulating the precursor concentration. The results indicated that the precursor concentration played remarkable influences on the morphology and photocatalytic ability. The mild reagent concentration was in favor of super-thin CuBi 2 O 4 nanosheet formation. CuBi 2 O 4 /TiO 2 NTAs with high reagent concentration exhibited high photocurrent and hydrogen production, and showed outstanding performance in the removal of organic dyes and heavy metal ions. The free radical production and the photocatalytic progress were introduced in detail. The high photocatalytic activity exhibits prospective foreground in industrial waste water treatment and novel energy resource development. [ABSTRACT FROM AUTHOR]

Nanofunctional photocatalysts are attractive materials in solar energy transformation for environmental protection and green energy source generation. TiO 2 nanoparticles are the most prospective photocatalysts due to the high photoactive property. In this paper, Ag nanoparticle-sensitized TiO 2 nanotube arrays (Ag/TiO 2 NTAs) were constructed as the photoelectrochemical platform for pollutant removal and hydrogen generation. TiO 2 NTAs were firstly obtained by the anodization method, and carbon layer was formed by the hydrothermal carbonization of glucose in different concentrations, and then Ag nanoparticles were deposited by carbon reduction of Ag+. Ag/TiO 2 NTAs could effectively decompose organic dye molecules and remove toxic heavy metal ions. The samples also could achieve visible light photocurrent and hydrogen generation. The surface plasmon resonance absorption and electron transfer path of Ag nanoparticles benefit photochemical performance improvement of TiO 2 NTAs. The construction of multifunctional platform of Ag/TiO 2 NTAs would cause extensive response and focus in the synergistic applications of semiconductor photocatalysts. [ABSTRACT FROM AUTHOR]

Graphene as a well-known electron cocatalyst can enhance the hydrogen-production performance of photocatalysts due to its excellent conductivity. For highly efficient graphene-modified TiO 2 photocatalyst, besides the speedy electron transfer via graphene, it is significant to raise the interfacial hydrogen-generation reaction rate on the graphene surface. In this paper, thiourea (TU) can covalently functionalize graphene and act as effective H+-adsorbed active sites to improve the hydrogen-production efficiency of graphene-modified TiO 2 (TiO 2 /rGO-TU). The TiO 2 /rGO-TU sample was successfully prepared by a facile nucleophilic substitution reaction between the thiol (-SH) of thiourea and carboxyl (-COOH) of graphene. The TiO 2 /rGO-TU could possess the maximum H 2 -generation rate of 241.83 μmol h−1 g−1, which was 2.33 and 6.60 times greater than that of TiO 2 /rGO and TiO 2 , respectively. The enhanced photocatalytic activity of TiO 2 /rGO-TU can be ascribed to the synergistic effect of graphene and thiourea, namely, the graphene functions as a cocatalyst to capture the photoexcited electrons of TiO 2 and the thiourea acts as effectual H+-adsorbed active sites to promote interfacial hydrogen generation. This study presents a feasible strategy for developing grephene-based photocatalysts for prospective applications in the hydrogen-production field. [ABSTRACT FROM AUTHOR]

TiO 2 nanotube arrays (TiO 2 NTAs) were mainly synthesized by the anodization of Ti foils, and the Ti mesh anodization was little researched. TiO 2 NTAs/Ti mesh showed remarkably high photocatalytic performance in pollutant treatment and photocurrent/hydrogen generation. In this paper, TiO 2 NTAs were synthesized on flexible three dimensional Ti mesh surface, and CdS/PbS sensitizers covered TiO 2 NTAs by the hydrothermal deposition. Especially, the S –CdS photocatalyst prepared by CdS sensitization showed strong photocurrent and photocatalytic pollutant removal capacity. RhB, MB dyes and Cr(VI) ions were effectively purified under solar irradiation, and samples also showed excellent visible light-driven photoelectric ability. Furthermore, the S –PbS photocatalyst prepared by PbS sensitization showed high photocatalytic water splitting performance. The functional material offers a flexible, low cost and high photocatalytic membrane for waste water treatment and photocurrent/hydrogen generation. [ABSTRACT FROM AUTHOR]

In this paper, a new sol-gel assisted solid-phase method for the preparation of nano BaTiO 3 ceramics is proposed to solve the shortcomings of too high temperature in solid-phase preparation and NO 2 pollution produced by sol-gel method. The TiO 2 precursor gel is used to encapsulate BaCO 3 , which can effectively reduce the temperature during calcination. In this study, XRD, FT-IR, XPS, TEM, SEM and TG-DSC were used to explore the structure and evolution of samples at different stages. In addition, the crystallization and growth process of BaTiO 3 were further studied. Then the energy band structure and electron hole recombination of different samples were analyzed by UV–Vis and PL spectra. Finally, the photocatalytic activity of different samples was investigated by photolytic water experiment. The results showed that BaTiO 3 was initially generated at 600 °C and pure phase BaTiO 3 was generated at 800 °C. In the photolytic water experiment, the samples calcined at 700 °C showed the best photocatalytic performance, with a hydrogen production rate of 43.74 μmol/g/h. [ABSTRACT FROM AUTHOR]