Sunlight-driven photocatalysis is at the forefront of sustainable technologies for the remediation of organic pollutants in industrial wastewater. In this study, we present the innovative synthesis of porous microspheres based on an S-scheme CuO/ZnO composite photocatalyst, inspired by the unique morphology of dried resurrection plants. X-ray diffraction confirmed the formation of highly crystalline CuO and ZnO phases, while UV-vis-NIR spectroscopy revealed exceptional sunlight harvesting capabilities, with optical absorption spanning the solar spectrum and a narrow bandgap of 1.4 eV. Under optimal conditions, the photocatalyst achieved a remarkable 97% degradation of Rhodamine B dye within just 60 min of solar irradiation. Systematic evaluation across varying compositions, pH values, and catalyst loadings highlighted robust photocatalytic performance. Moreover, the composite demonstrated outstanding stability and reusability, retaining high activity over more than five consecutive cycles. This full-solar-spectrum-active, biomimetic photocatalyst offers a promising platform for the efficient, sunlight-driven purification of hazardous organic effluents, with significant implications for environmental sustainability and public health.
To ensure sustainable management and the availability of water and sanitation for all, a UN sustainable development goal (SDG) focused on promising methods to eliminate aqueous pollutants is urgently required. In this regard, solar photocatalysis, driven by freely available sunlight using low-cost, reusable photocatalysts, is a promising approach. In this context, we present a novel full-solar-spectrum photocatalyst with promising efficiency attributed to its laddered heterojunction and Ag-based plasmon enhanced activity. Specifically, it comprised Co2+-doped zinc-ferrite nanoparticles embedded on zinc oxide sheets that were later conformally coated with a small weight fraction (2.5%) of Ag under sunlight. The photocatalyst was optimized for different synthesis methods, post-synthesis temperatures, and different compositions with orange G as a model pollutant. Unlike previous reports, without any scavengers, the photocatalyst was effective for highly polluted water with a chemical oxygen demand (COD) of ∼740 ppm, eliminating 66% of it within an hour. We have coined a new term, solar photo-oxidation efficiency (SPOE), to describe the photocatalyst's performance. SPOE was directly dependent on the pollutant concentration and was found to be 72% for 400 ppm ciprofloxacin, with an apparent quantum yield of 36%. The promising activity of our photocatalyst continued even after several reuses. The generation of hydroxyl and superoxide radicals was confirmed by respective confirmatory tests. Scavenging tests indicated the highest contribution of superoxide radicals and holes in photodegradation. Our photocatalyst is promising and holds enormous potential for use in the treatment of diverse pollutants.
This paper presents an in-depth investigation into the synthesis and characterization of Ti3C2Tx MXene and its noble metal-decorated variants (Ti3C2Tx-Ag and Ti3C2Tx-Au), underscoring their viability for the fabrication of high-performance SO2 sensors. A self-reduction approach was employed to decorate Ti3C2Tx MXene with noble metals, and comprehensive characterization techniques enabled a detailed analysis of their properties. The formation of multilayered, and delaminated Ti3C2Tx and its successful decoration with Ag and Au nanoparticles (NPs) was confirmed using X-ray diffraction (XRD) analysis. The accordion-like morphology of multilayered Ti3C2Tx and transparent sheet-like structure were observed via field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). SO2 sensing measurements revealed that Ti3C2Tx, along with its Ag- and Au-decorated Ti3C2Tx, demonstrated room-temperature SO2 sensing with rapid response and recovery times. The loading of noble metals significantly improved sensitivity, with Ag-Ti3C2Tx showing the highest response. Density functional theory (DFT) calculations were performed to elucidate the mechanism underlying the enhanced sensitivity following noble metal decoration. The study results forecast a significant contribution to the development of Ti3C2Tx MXene for gas sensing applications.
Heterojunctions comprising wide and narrow gap materials with distinct band edge potentials always remain an ideal choice to operate under wide spectrum of solar light for the photocatalytic reactions. In this context, integrating ZnO and g-C3N4 gains prominent interest from the prospect of easy preparation and suitable band edge positions to form the heterojunctions. In the current work, the ZnO/g-C3N4 is obtained by annealing the pre-crystallized materials (550 °C) and characterized by using various analytical techniques. The X-ray diffraction results confirmed the composite formation, while the optical response measurements revealed the light absorption ability in the visible region. The ZnO/g-C3N4 enabled the faster degradation of indigo carmine dye compared to individual phase counterparts under the light illuminated conditions. This was attributed to the formation of S-scheme heterojunction which allowed energetic charge carriers to participate in the reactions and was later supported with radical scavenging experiments. Furthermore, the density functional theory calculations indicated the formation of interfacial bonds such as Zn–N and Zn–C which played a vital role in boosting the charge carrier separation process.
Treating infections remains a significant challenge, driving the ongoing pursuit of novel drug candidates. Heterocyclic compounds, such as those containing imidazole and thiazole rings, are well-known for their diverse therapeutic and pharmaceutical applications. In this study, we designed, synthesized, and characterized a series of six novel compounds incorporating these two five-membered rings. The synthesis involved the reaction of different phenacyl bromides with imidazole-hydrazinecarbothioamide to produce imidazole-thiazole hybrid derivatives, which were confirmed through IR, 1H NMR, 13C NMR, and mass spectrometry analyses. The antimicrobial activities of the derivatives were evaluated against three bacterial strains and one fungal strain using the serial dilution method, with their minimum inhibitory concentrations (MICs) determined. Notably, all the derivatives exhibited moderate antimicrobial activity. Cytotoxicity assessment revealed that derivative 5a was particularly excellent, displaying significant inhibition with an IC50 value of 33.52 μM. Furthermore, molecular docking, ADME, and molecular dynamics simulations were conducted, focusing on the interaction between derivative 5a and the protein (PDB ID: 6LUD) to elucidate the stability of the interaction.
