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A facile one-pot microwave-assisted synthesis prepared a new noble metal-free heterostructure of In 2 S 3 /In 2 O 3 nanosheets for blue LED-light-induced photocatalytic water splitting. The appropriate InCl 3 concentrations and reaction temperatures can grow the In 2 S 3 /In 2 O 3 nanosheets with higher photocatalytic water splitting for hydrogen production under blue-LED light irradiation. In addition, the optimized In 2 S 3 /In 2 O 3 nanosheets exhibited a higher hydrogen production rate is 618.0 μmolh−1g−1 in seawater without adjusted pH values under blue-LED light irradiation. Furthermore, the reusability of In 2 S 3 /In 2 O 3 nanosheets revealed the gradual increase of photocatalytic hydrogen production efficiency in four cycles. This phenomenon shall be attributed to the reaction of In 2 S 3 /In 2 O 3 nanosheets and seawater to form In 2 S 3 /In 2 O 3 /In(OH) 3 nanosheets, which can improve the recombination of the photogenerated charge carriers and light-harvesting capacity to promote their photocatalytic hydrogen production. [Display omitted] • In 2 S 3 /In 2 O 3 nanosheets were prepared using one-pot microwave-assisted synthesis. • In 2 S 3 /In 2 O 3 nanosheets exhibited higher photocatalytic water or seawater splitting. • In 2 S 3 /In 2 O 3 /In(OH) 3 nanosheets can be synthesized under photocatalytic seawater splitting. • In(OH) 3 can enhance the separation charge carriers and light-harvesting capacity. [ABSTRACT FROM AUTHOR]

This study synthesized the In(OH) 3 –In 2 S 3 nanosheet via a simple hydrothermal method. The different amounts of In(OH) 3 –In 2 S 3 nanosheet used to synthesize In(OH) 3 –In 2 S 3 –Cu 2 O composite by a wet chemical method. FESEM, FETEM, XRD, XPS, BET, UV–vis DRS, and PL spectroscopy characterized the In(OH) 3 –In 2 S 3 –Cu 2 O composite. Compared with In(OH) 3 –In 2 S 3 nanosheet, In(OH) 3 –In 2 S 3 –Cu 2 O composite can exhibit the synergistic effects of higher specific surface area, higher light-harvesting capacity, and accelerating the separation and migration of photogenerated charge carriers. In addition, In(OH) 3 –In 2 S 3 –Cu 2 O nanofiber was fabricated via a facile electrospinning process at the different amounts of In(OH) 3 –In 2 S 3 nanosheet. The manufacturing process offers many advantages, such as simplicity, low temperature, and without templates. The effect of operational parameters (such as the reaction conditions of photocatalysts, pH values, sacrificial reagents, and light sources) on the photocatalytic hydrogen production of In(OH) 3 –In 2 S 3 –Cu 2 O nanofiber was investigated. The results indicate that the appropriate reaction conditions of In(OH) 3 –In 2 S 3 –Cu 2 O nanofiber can reveal higher efficient photocatalytic water splitting than commercial TiO 2 or ZnO nanofiber under blue light LED excitation. Furthermore, In(OH) 3 –In 2 S 3 –Cu 2 O nanofiber can provide a simple fabrication process, high photocatalytic activity, and high reusability shall be beneficial for the practical application of photocatalytic hydrogen production. [Display omitted] • In 2 S 3 –In(OH) 3 –Cu 2 O nanofiber (NF) was prepared using the electrospinning method. • In 2 S 3 –In(OH) 3 –Cu 2 O NF exhibited enhanced photocatalytic activity for H 2 evolution. • The HER of In 2 S 3 –In(OH) 3 –Cu 2 O NF is 14.5 times higher than In(OH) 3 NF. • Cu 2 O nanoparticles can enhance charge-carries separation and transfer efficiency. • The mechanism for the photocatalytic H 2 production with In 2 S 3 –In(OH) 3 –Cu 2 O was explained. [ABSTRACT FROM AUTHOR]

TiO 2 nanostructures (NSs) doped with varying Fe concentrations are synthesized using the sol-gel process, followed by annealing in 1 atm environment at 470 ℃ for 3 h. Anatase TiO 2 crystal structure and defect levels are characterized using XRD, HRTEM, SEM-EDS, XPS, Raman, EPR, PL, and TR-PL techniques. Remarkably, the addition of approximately 4 wt% Fe dopant had no discernible impact on the crystal structure of the anatase TiO 2. Furthermore, energy levels including V O , Ti i ∙ ∙ ∙ , Fe3+/Fe2+, Fe3+/Fe4+, and Ti3+/Ti4+ are identified. The optical band-gap of TiO 2 is reduced from 3.077 to 2.352 eV and its carrier lifetime is extended from 6.53 ns to 9.12 ns with Fe contents ranging from 0 to approximately 2 wt%. The CO 2 photoreduction results demonstrate that Fe-doped TiO 2 outperforms commercial TiO 2 (P25) in terms of the photoreduction rate. Particularly, TiO 2 NSs doped with 2 wt% Fe exhibit the highest CO 2 photoreduction rates, yielding approximately 35.19×10 2 and 66.84×10 2 μmol‧g 1‧min 1of CO and CH 4 , respectively; thereby surpassing P25 by factors of 1.26 and 3.1, respectively. Therefore, Fe-doping can reduce the optical band-gap and extend the carrier lifetime of TiO 2 photocatalysts, resulting in superior CO 2 photoreduction capabilities. Moreover, the significance of electrons in the CO 2 photoreduction process, as evidenced by the findings from the EPR spectrum and CO 2 photoreduction, underscores the importance of an appropriate Fe content, such as 2 wt% used in this study, for enhancing the photoreduction abilities and potential applications of TiO 2 in CO 2 photoreduction. [Display omitted] • Fe-dopant shows no effect on anatase TiO 2 crystal structure with Fe contents increasing to 4wt%. • Energy levels including Ti i ... , V O ∙ ∙ , V O ∙ , Fe3+/Fe2+, Fe3+/Fe4+, and Ti3+/Ti4+ affect CO 2 photoreduction efficiency. • 2wt% Fe-doped TiO 2 shows reduced bandgap and extended carrier lifetime of 2.352eV and 9.12ns, respectively. • 2wt% Fe-doped TiO 2 exhibits higher CO 2 photoreduction rate than in P25. [ABSTRACT FROM AUTHOR]

The novel ZnIn 2 S 4 /ZnO heterostructures can prepare by combining a facile hydrothermal and wet chemical methods. Various microscale and nanoscale characterization techniques analyzed the surface topography, structural and optical properties of the ZnIn 2 S 4 /ZnO heterostructures. The addition amount of ZnIn 2 S 4 nanosheets plays an essential role in controlling the optical properties of ZnIn 2 S 4 /ZnO heterostructures. ZnIn 2 S 4 /ZnO heterostructures can improve charge carriers separation and specific surface area for enhancing the photocatalytic decomposition of the 4-aminobenzoic acid solution and hydrogen evolution under blue LED irradiation. Furthermore, ZnIn 2 S 4 /ZnO heterostructures also revealed high photocatalytic stability and reusability for long-term reaction processes. Therefore, ZnIn 2 S 4 /ZnO heterostructures can be used as efficient visible-light-induced photocatalysts for the practical applications in water splitting and wastewater treatment. Image 1 • ZnO modified ZnIn 2 S 4 nanosheets were prepared by a wet chemical approach. • The heterostructures can greatly enhance visible-light hydrogen evolution activity. • The photodecomposition mechanism of PABA was mainly via h+ and ·OH radicals. • ZnIn 2 S 4 /ZnO heterostructures revealed excellent photocatalytic reusability and stability. [ABSTRACT FROM AUTHOR]

Abstract This work describes the direct fabrication of Ag nanoparticles on pyramidal silicon using a facile, one-step, electroless deposition process at room temperature with short reaction time (3 min). The resulting device could use for rapid drug detection based on surface-enhanced Raman scattering (SERS). The size of the silicon pyramids controlled by altering the texturing time of the silicon substrate. Spin coating was used to enable the rapid deposition of rhodamine 6G molecules (3 min) on the Ag nanoparticles. The resulting pyramidal silicon decorated with Ag nanoparticles provides large specific area as well as hot spots to promote localized surface plasmon resonance, resulting in notable SERS enhancement and a low 5-fluorouracil detection limit (10−6 M). Highlights • Facile electroless deposition to grow Ag nanoparticles (NPs) on pyramidal silicon. • Room temperature growth of Ag NPs using short (3 min) reaction time. • Surface-enhanced Raman scattering (SERS) tests using rhodamine 6G on Ag NPs/Si pyramids • Size of the silicon pyramids controlled by the texturing time appears to be critical. • Very low detection limit (10−6 M) of the Ag NP-based SERS sensor for 5-fluorouracil. [ABSTRACT FROM AUTHOR]