Unique hierarchical SiO2@ZnIn2S4 marigold flower like nanoheterostructure for solar hydrogen production

Turning trash to treasure: Innovative use of exhausted desiccant waste supported zinc indium sulphide for sustainable photocatalytic abatement of tetracycline

Employing an affordable and sustainable visible-light-driven system is crucial for organic pollutant abatement, in the field of photocatalysis. In the present investigation, a pioneering photocatalyst zinc indium sulphide, ZnIn2S4 (ZIS) supported on a silica gel matrix, SiO2 (SG) which is the leftover material after multiple rounds of dehumidification processes, was synthesized. The fabrication of the heterojunction facilitated enhancement in light absorption and charge separation efficiency. The photocatalytic performance was evaluated through the degradation of tetracycline (TC) under light irradiation. The nano-photocatalyst experienced detailed analysis using spectroscopic and microscopic methods. The ZIS/SG catalyst exhibited remarkable efficiency in degrading TC under visible light conditions, achieving a nearly 98-99% degradation. This performance surpassed the degradation rates of the original ZIS and SG catalysts by 3.6 and 4.45 times, respectively. Additionally, the catalyst was effectively used to control TC levels in real-time within pharmaceutical plant effluent, resulting in a degradation efficiency of 78.2%. With affordability, enhanced TC mineralization, and recyclability for up to six runs (efficiency ∼ 85%), the ZIS/SG photocatalyst exhibits desirable qualities of an ideal one. This innovative nano-photocatalyst introduces new possibilities for improving the process of photocatalytic decontamination of tenacious emerging pollutants by providing satisfactory reusability and stability.

Fabrication and Characterization of Nanostructured Rock Wool as a Novel Material for Efficient Water-Splitting Application

Rock wool (RW) nanostructures of various sizes and morphologies were prepared using a combination of ball-mill and hydrothermal techniques, followed by an annealing process. Different tools were used to explore the morphologies, structures, chemical compositions and optical characteristics of the samples. The effect of initial particle size on the characteristics and photoelectrochemical performance of RW samples generated hydrothermally was investigated. As the starting particle size of ball-milled natural RW rises, the crystallite size of hydrothermally formed samples drops from 70.1 to 31.7 nm. Starting with larger ball-milled particle sizes, the nanoparticles consolidate and seamlessly combine to form a continuous surface with scattered spherical nanopores. Water splitting was used to generate photoelectrochemical hydrogen using the samples as photocatalysts. The number of hydrogen moles and conversion efficiencies were determined using amperometry and voltammetry experiments. When the monochromatic wavelength of light was increased from 307 to 460 nm for the manufactured RW>0.3 photocatalyst, the photocurrent density values decreased from 0.25 to 0.20 mA/mg. At 307 nm and +1 V, the value of the incoming photon-to-current efficiency was ~9.77%. Due to the stimulation of the H+ ion rate under the temperature impact, the Jph value increased by a factor of 5 when the temperature rose from 40 to 75 °C. As a result of this research, for the first time, a low-cost photoelectrochemical catalytic material is highlighted for effective hydrogen production from water splitting.

Amino-functionalized NH2-MIL-125(Ti)-decorated hierarchical flowerlike Znln2S4 for boosted visible-light photocatalytic degradation

Developing novel heterojunction photocatalysts with visible-light response and remarkable photocatalytic activity have been verified to applying for the photodegradation of antibiotics in water environment. Herein, NH₂-MIL-125(Ti) was integrated with flowerlike ZnIn₂S₄ to construct NH₂-MIL-125(Ti)@ZnIn₂S₄ heterostructure using a one-pot solvothermal method. The photocatalytic performance was evaluated by the degradation of tetracycline (TC) under visible light illumination. The optimized NM(2%)@ZIS possesses a photodegradation rate (92.8%) and TOC removal efficiency (58.5%) superior to pristine components, which can be principally attributed to the positive cooperative effects of well-matched energy level positions, strong visible-light-harvesting capacity, and abundant coupling interfaces between the two. Moreover, the probable TC degradation mechanism was also clarified using the active species trapping experiments. This study inspires further design and construction of NH₂-MIL-125(Ti) and ZnIn₂S₄ based photocatalysts for effective removal of antibiotics in water environment.