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The widespread use of antibiotics poses significant risks to both human health and the environment. Among various approaches, photocatalysis has emerged as a promising method for addressing the issue of antibiotic residues. BiOCl, a semiconductor photocatalyst, has attracted attention due to its distinctive structure. However, the limited light utilization efficiency of its ultraviolet light responsiveness remains a challenge. In this study, we developed a heterojunction by decorating BiOCl with metal-organic frameworks (MOFs) MIL-100(Cr), referred to MIL-100(Cr)/BiOCl (MB), to efficiently treat the antibiotic oxytetracycline (OTC) under visible light irradiation. Various analytical techniques, including X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and scanning electron microscopy, were used to verify the formation of the MB heterojunction. The interaction between MIL-100(Cr) and BiOCl in the MB heterojunction substantially enhances the responsiveness to visible light, increases the specific surface area, facilitates the separation and transfer of charged carriers, and ultimately results in a significant enhancement in visible light-driven photocatalytic performance for OTC degradation. This study explores the application of narrow/wide band gap nanomaterials-based nanocomposites in environmental remediation by constructing heterojunctions. [Display omitted] • A chrome-based metal organic frameworks fabricated BiOCl heterojunction was facilely constructed. • This heterojunction demonstrates efficacy in the photocatalytic degradation of oxytetracycline. • This heterojunction greatly enhances the responsibility to visible light. • This heterojunction effectively promotes the charged carriers separation and transfer. • A reasonable mechanism for the enhanced photocatalytic activity is proposed. [ABSTRACT FROM AUTHOR]

The design and construction of appropriate photocatalysts in heterojunction mode is an effective way to improve photocatalytic performance. Herein, a metal-organic frameworks (MOFs) fabricated heterojunction constructed by MOF-902(Ti) and BiOCl (noted as TB) was developed to treat efficiently antibiotic tetracycline (TC) under visible light irradiation. TB exhibits a higher photodegradation ability than MOF-902(Ti) and BiOCl. Various characterization including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), and scanning electron microscope (SEM), etc. verify the formation of TB heterojunction, which improves significantly the visible light response, increases the specific surface area/pore volume, promotes effectively charged carriers separation and transfer, and ultimately enhances greatly the photocatalytic performance. Reactive species trapping demonstrates that·O 2 -, e-, and h+ participate cooperatively in the photodegradation of TC. A possible mechanism for the enhanced photocatalytic activity of TB heterojunction is proposed. [Display omitted] • A metal organic frameworks fabricated BiOCl heterojunction is facilely constructed. • This heterojunction is suitable for photocatalytic degradation of tetracycline. • This heterojunction improves significantly the visible light response. • This heterojunction promotes effectively charged carriers separation and transfer. • A possible mechanism for enhanced photocatalytic activity is proposed. [ABSTRACT FROM AUTHOR]

Few-layered MoSe 2 nanosheets were grown vertically on TiO 2 nanorods (TNr) to synthesis a direct Z-scheme heterojunction, exhibiting efficient piezocatalytic and piezo-photocatalytic performance. Moreover, a piezo-photoelectric synergistic effect of nanocomposites was also observed by current outputs. Our results highlight significance in the design of heterojunction for capturing fluid mechanical energy and improving piezo-photocatalytic synergistic effect. [Display omitted] Nano-semiconductor materials coupled with piezoelectric effect have received extensive attention due to their wide application in catalysis. In this work, few-layered MoSe 2 nanosheets were grown vertically on TiO 2 nanorods (TNr) to synthesize a direct Z-scheme heterojunction, exhibiting efficient piezocatalytic and piezo-photocatalytic performance. The MoSe 2 /TNr heterostructure exhibited superior piezoelectric degradation efficiency, successfully removing over 98% of RhB within 360 s under continuous magnetic stirring in dark. Compared with piezocatalysis, the piezo-photocatalytic system possessed higher degradation efficiency and cycle stability. Furthermore, a piezo-photoelectric synergistic effect of nanocomposites was observed by current outputs. Under stirring conditions, the current density of depleted MoSe 2 /TNr and MoSe 2 nanosheets were respectively 6.3 μA/cm2 and 5.5 μA/cm2. When light and stirring were applied, the MoSe 2 /TNr current density increased twice to 13.2 μA/cm2, while the MoSe 2 nanosheets didn't exhibit improvement. Through the direct Z-scheme heterojunction of MoSe 2 /TNr, photoexcitation and piezoelectric polarization work together to effectively replenish carriers under light irradiation, and then rapidly separate free charges through piezopotential. This work broadens the application prospects of piezocatalysis and piezo-photocatalysis in renewable energy harvesting and water purification. [ABSTRACT FROM AUTHOR]

• A hollow dodecahedron-shaped N-doped C (NC)/CoSe 2 is fabricated via self-sacrificing strategy. • The higher HER rate of CdS/N-doped C/CoSe 2 (CCE50) achieved in alkaline media may be attributed to the accumulation of O 2. • CCE50 converts CO 2 to C 2 H 2 at a rate of 2.8 μmol h−1 g cat −1. • The introduction of an Ohmic contact has resulted in a 15.7-fold increase in the HER for type I CdS/NC. • Extra valence electrons of NC raise the Fermi level to regulate electronic structures. A hollow dodecahedron-shaped N-doped carbon (N-C) coated with CoSe 2 nanoparticles are fabricated via MOF-derived self-sacrificing strategy based on Kirkendall Effect. By coupling with CdS nanodots, the optimal Ohmic-type functionalized type I heterojunction CdS/N-C/CoSe 2 (CCE50) exhibits a significant photocatalytic hydrogen evolution reaction (PHER) rate of 19317.3 μmol h−1 g cat −1 that is 15.7 and 33.7 folds higher than type I CdS/N-C heterojunction (1230.3 μmol h−1 g cat −1) and pure CdS respectively, and successfully transfers the source of photo-corrosion to obtain stable PHER for 5 cycles. Moreover, the CCE50 in alkaline media (pH = 12) achieves a 1.6-fold PHER rate higher than that in the original triethanolamine (TEOA) aqueous solution (pH≈8), where electron paramagnetic resonance (EPR) result shows that it is attributed to the accumulation of O 2 –. The effective PHER rate can be attributed to the synergistic effect of higher light absorption in hollow CCE50 with multiple scattering and the introduction of Ohmic contact. Besides, the successful conversion from CO 2 to C 2 H 2 under 80 kPa CO 2 pressure is detected firstly on CdS-based photocatalyst (the conversion rate is 2.8 μmol h−1 g cat −1) without other C1 or C2 gas products. EPR, in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) tests, Kelvin Probe Force Microscopy (KPFM) and density functional theory calculations, etc. have illustrated and verified the photocatalytic mechanism for Ohmic contact-enhancing type I heterojunction, which promotes hydrogen production in alkaline media and C 2 H 2 generation from CO 2. [ABSTRACT FROM AUTHOR]

• The possibility of functioning as a co-catalyst of Cu 2 Se was primarily evaluated by virtue of DFT calculations. • Cu 2 Se/CdS 0.95 Se 0.05 Ohmic-type heterojunction photocatalysts were fabricated via facile in situ solvothermal method. • The highest HER rate over Cu 2 Se/CdS 0.95 Se 0.05 is 27.4 times greater than that of pure CdS nanowires. The development of efficient co-catalysts for promoting solar-driven water splitting to hydrogen (H 2) energy conversion is of increasing importance but still a challenging scheme. In the present work, a noble-metal-free copper selenide (Cu 2 Se) is primarily evaluated the possibility of functioning as a co-catalyst for enhancing photocatalytic H 2 evolution activity by virtue of density functional theory (DFT) calculations. Then, the photocatalysts CdS 0.95 Se 0.05 nanowires (NWs) decorated with Cu 2 Se nanoparticles (NPs) as co-catalyst are designed and successfully fabricated via a hydrothermal method. Under visible light (λ ≥ 400 nm) illumination, the as-prepared Cu 2 Se/CdS 0.95 Se 0.05 nanocomposites loading with 20 mol% of Cu 2 Se NPs exhibits the highest photocatalytic activity with an H 2 generation rate of 570.7 μmol·h−1 and a corresponding apparent quantum efficiency (AQE) of 31.26%, which is about 7.1 and 27.4 times greater than that of pristine CdS 0.95 Se 0.05 and CdS NWs, respectively. Theoretical calculations and experimental measurements demonstrate that the excellent activity of the hybrid catalysts is ascribed to the formation of Ohmic-type heterojunctions between CdS 0.95 Se 0.05 semiconductor and semi-metallic Cu 2 Se, which can not only facilitate the charge carriers separation and transportation but also improve the surface H 2 -evolution kinetics. [ABSTRACT FROM AUTHOR]

• CoSe 2 /CdS 0.95 Se 0.05 Schottky heterojunction were fabricated via simple method. • Se-doping can lower the work function of CdS NWs, availing the electrons escaping. • The highest HER rate of CoSe 2 /CdS 0.95 Se 0.05 is ~66 times higher than that of CdS NWs. • CoSe 2 can efficiently boost the separation and migration of charge carriers. Novel CoSe 2 nanobelts/Se-decorated CdS nanowires heterojunctions were successfully constructed via combining strategies of Se-doping and in situ loading of CoSe 2 nanobelts. Under visible-light (λ ≥ 400 nm) irradiation, the CoSe 2 /CdS 0.95 Se 0.05 nanocomposites exhibit significantly enhanced photocatalytic H 2 -evolution activities. The peak value of the H 2 -generation rate of 13894.8 μmol·h−1·g−1 is achieved with an apparent quantum efficiency (AQE) of 76.1%, which is approximate 66.7 times higher than that of pure CdS nanowires. Experimental investigations and theoretical calculations demonstrate that the enhanced photocatalytic H 2 -evolution performance originates from the synergetic effects of 1) the Se-doping to form CdS 0.95 Se 0.05 nanowires, which can reduce the electrostatic potential energy of CdS catalyst to promote electrons migration for reducing the recombination efficiency of electron/hole pairs; and 2) the in situ loading of CoSe 2 co-catalyst to construct the Schottky heterojunction between CoSe 2 and CdS 0.95 Se 0.05 nanowires, which can not only efficiently boost the separation of charge carriers, but also provide sufficient active sites for reducing H+ to H 2 subsequently. [ABSTRACT FROM AUTHOR]