In Situ Photodeposition of Cobalt Phosphate (CoHxPOy) on CdIn2S4 Photocatalyst for Accelerated Hole Extraction and Improved Hydrogen Evolution

Surface modification of heterostructured Bi8W4O24/ZrO2@GO composite via low-pressure cold plasma for boosting photocatalytic potential against Basic fuchsin and Bismarck brown Y dyes

The widely used dyes, Basic fuchsin (BF) and Bismarck brown Y (BBY), pose significant risks to water resources and human health, necessitating efficient removal methods. Semiconductor-based heterogeneous photocatalysis offers an eco-friendly solution. However, improving the photocatalyst's efficiency remains a challenge. This study aims to fabricate a promising Bi8W4O24/ZrO2@GO (BWOZG) heterojunction via hydrothermal approach, followed by low-pressure cold plasma (LPCP) treatment to improve its properties for environmental remediation of BF and BBY dyes along with industrial wastewater. The prepared composites were analyzed via DLS, UV-visible spectroscopy, SEM-EDX, FTIR, XRD, and EPR. The findings indicated that the LPCP-treated BWOZG has z-average of 225 ± 5 nm, zeta potential of - 38.74 ± 2 mV, band gap of 2.20 eV, a porous morphology, and mixed orthorhombic Bi8W4O24 and tetragonal ZrO2 phases. LPCP-treated BWOZG composite exhibited 5% increase in degradation efficiency of BF (99.7%) at pH = 6, catalyst dose = 20 mg L-1, dye dose and irradiation time = 10 mg L-1/30 min, and 6% for BBY (98%) at pH = 5, catalyst dose = 30 mg L-1, dye dose and irradiation time = 10 mg L-1/30 min, and 80.41% reduction in COD of industrial wastewater. The successful degradation of dyes to nontoxic species was confirmed by FTIR. The formation of •OH and O2-• radical species during photocatalytic process was confirmed by EPR analysis. Kinetics study showed the best fitness of the pseudo-first-order model on experimental data. LPCPT-BWOZG retained 91 and 89% recyclability after five cycles of BF and BBY degradation, respectively, and good broad-spectrum bactericidal activity for E. coli and S. aureus, demonstrating its potential as antibacterial photocatalytic materials for oxidation of organic pollutants in aqueous media to enhance the environmental safety.

Iron hydroxyphosphate electro-Fenton catalyst for efficient removal of sulfamethoxazole and resource recycling into slow-release fertiliser ammonium ferrous phosphate

Although the electro-Fenton (EF) process is effective for wastewater treatment, recycling spent catalysts remain a major challenge. Therefore, we introduce a reuse strategy for spent catalysts where an iron hydroxyphosphate [Fe5(PO4)4(OH)3·2H2O] catalyst is utilized. Fe5(PO4)4(OH)3·2H2O obtained •OH and •O2- by activating in-situ produced H2O2, and the degradation rate of sulfamethoxazole reached 94.5% after 120 min and showed excellent stability (maintained above 90%) for 10 cycles. Finally, the used catalyst was converted into slow-release ammonium ferrous phosphate (NH4FePO4·H2O) fertiliser at a conversion rate of 85.6%. NH4FePO4·H2O significantly promoted plant and seed growth within 6 days, highlighting the contribution of the resource recycling of the spent catalyst. This study serves as a valuable reference for the efficient utilization of spent catalysts. This study successfully applied EF catalysts and explored the recycling of spent catalysts.

Rational Photodeposition of Cobalt Phosphate on Flower-like ZnIn2S4 for Efficient Photocatalytic Hydrogen Evolution

The high electrons and holes recombination rate of ZnIn2S4 significantly limits its photocatalytic performance. Herein, a simple in situ photodeposition strategy is adopted to introduce the cocatalyst cobalt phosphate (Co-Pi) on ZnIn2S4, aiming at facilitating the separation of electron-hole by promoting the transfer of photogenerated holes of ZnIn2S4. The study reveals that the composite catalyst has superior photocatalytic performance than blank ZnIn2S4. In particular, ZnIn2S4 loaded with 5% Co-Pi (ZnIn2S4/5%Co-Pi) has the best photocatalytic activity, and the H2 production rate reaches 3593 μmol·g-1·h-1, approximately double that of ZnIn2S4 alone. Subsequent characterization data demonstrate that the introduction of the cocatalyst Co-Pi facilitates the transfer of ZnIn2S4 holes, thus improving the efficiency of photogenerated carrier separation. This investigation focuses on the rational utilization of high-content and rich cocatalysts on earth to design low-cost and efficient composite catalysts to achieve sustainable photocatalytic hydrogen evolution.

Fabrication of Bi2O3/Bismuth Titanates Modified with Metal-Organic Framework-In2S3/CdIn2S4 Materials for Electrocatalytic H2 Production and Its Photoactivity

Compositional and structural elucidation of the materials is important to know their properties, chemical stability, and electro-photoactivity. The heterojunction electrocatalyst and photocatalyst activity could open a new window for solving the most urgent environmental and energy problems. Here, for the first time, we have designed and fabricated Bi2O3/bismuth titanates modified with MOF-In2S3/CdIn2S4 materials by a stepwise process. The detailed structural elucidation and formation of mixed composite phases were studied in detail. It has been found that the formed composite was efficiently utilized for the electrocatalytic H2 production reaction and the photocatalytic degradation of tetracycline. XRD patterns for the metal-organic framework-In2S3 showed a main compound of MOF, and it was assigned to a MIL-53 MOF phase, with a monoclinic structure. The addition of CdCl2 onto the MOF-In2S3 phase effectively produced a CdIn2S4 flower platform on the MOF rods. The uniform dispersion of the bismuth titanates in MOF-In2S3/CdIn2S4 materials is detected by mapping of elements obtained by dark-field HAADF-STEM. Finally, the predictions of how to integrate experiments and obtain structural results more effectively and their common development in new heterojunctions for electro-/photocatalytic applications are presented.

Advanced Photocatalytic Nanomaterials for Energy Conversion and Environmental Remediation

With the rapid development of the economy and society, the problem of energy shortage and environmental pollution is receiving more and more attention [...].