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As a persistent antibiotic, tetracycline is widely used in medical and livestock farming fields. However, the long-term accumulation effect of tetracycline has a significant impact on the ecosystem. In this research, we integrated the processes of adsorption-photocatalytic degradation for organic pollutants by combining Sichuan Pepper shell biochar adsorption, TiO 2 Nanorods photocatalytic oxidation, and Au nanoparticles Localized Surface Plasmon Resonance. The findings demonstrated that the specific surface area of Au nanoparticles/TiO 2 nanorods/biochar has increased by 1287.6 m2/g compared to TiO 2. Furthermore, when TiO 2 is compounded with biochar, its particle size reduces by approximately half and forms C-Ti and N-Ti bonds. The composite catalyst exhibited the highest removal rate for tetracycline, nearly four times that of commercial TiO 2 (P25), showing excellent application prospects. The enhanced composite structure improved its ability to capture sunlight, leading to more effective photocatalysis. This research explains the composite and synergistic mechanism of biochar, TiO 2 nanorods, and Au nanoparticles, which could guide the removal of organic pollutants. [Display omitted] • Au/TiO 2 /BCP can achieve cooperative control over the adsorption and photocatalysis of organic pollutants. • Revealing the technical value and potential of Sichuan pepper shell as an adsorbent. • Exploring the coupling mechanism after functionalization with TiO 2 nanorods and Au-NPs. • A systematic study of photocatalytic mechanism is proposed. [ABSTRACT FROM AUTHOR]

As a wastewater treatment technology, the activity of advanced oxidation process (AOPs) is strongly dependent on pH value. Herein, considering the low activity of AOPs under alkaline conditions, the acid organic ligand (nitrilotriacetic acid, NTA) was chosen to design Co-NTA metal-organic catalyst for efficient photo-Fenton reaction at full pH range. The experimental results indicate the acid ligands in Co-NTA offers more·OH that can achieve high activity under alkaline conditions. To further enhance the electron injection ability and redox cycles of Co(II)/Co(III), Ferrocene (Fc) nanoparticles was introduced to form bimetallic organic catalyst Fc-Co-NTA. The mechanism study indicates that the synergistic effect between Co-NTA and Fc promotes the activation of potassium persulfate and improves the stability of the catalyst under extreme pH conditions, while the π-π interaction between TC and Fc-Co-NTA can improve the electron injection capability and accelerate the production of·OH/SO 4 •-, so as to accelerate the redox cycles of Fe(II)/Fe(III) and Co(II)/Co(III), bringing about prolonged carrier lifetime and better photocatalytic activity. The possible degradation pathway of TC was investigated by Fukui function and LC-MS. A machine learning model is used to optimize the synthesis and photocatalytic parameters of Fc-Co-NTA. This study provides a new design idea to prepare highly efficient and stable photo-Fenton advanced oxidation technology at full pH range. ● Fc-Co-NTA with nitrilotriacetic acid ligands and aromatic rings was designed. ● The nitrilotriacetic acid ligands offers more·OH under alkaline conditions. ● Machine learning is used to optimize the experiment parameters of Fc-Co-NTA. ● An efficient photo-Fenton degradation of tetracycline at full pH range is achieved. ● A systematic study of photocatalytic mechanism is proposed. [ABSTRACT FROM AUTHOR]

Recent years, many scholars have been greatly intrigued by the large amounts of emerging antibiotics pollutants (such as tetracycline, penicillin, etc.) in natural water environments. Photo-Fenton oxidation, a highly advanced oxidation technique, has been seen as a promising way to effectively break down these pollutants by generating a great deal of reactive oxygen species (ROS). Herein, iron phthalocyanine nanodots (FePc)/ultra-thin porous carbon nitride (UPCN) nanocomposites were successfully prepared by thermal polymerization and calcination processes. In the system with a small amount (10 μL) of hydrogen peroxide (H 2 O 2) and natural pH conditions, the 1%-FePc/UPCN nanocatalcatalyst had the best degradation effect, and the TC removal rate reached 89% within 20 min and 99% within 60 min. The excellent performance of the nano-composites is ascribed to the large surface area, multiple active sites, small pore size, easy excitation and fast transfers of photogenerated carriers induced by π - π bond. In addition, the improvement of the degradation of TC is also due to the synergistic effect of the photocatalytic reaction center dominated by UPCN and Fenton reaction center dominated by FePc in the system, simultaneously. In this study, a synergistic dual-reaction center catalytic system was constructed to provide new insights and strategies for the degradation of organic pollutants in natural water environments. [Display omitted] • FePc/UPCN nanocomposite was successfully prepared by loading FePc nanodots on UPCN. • A small amount of H 2 O 2 (10 μL) was required for optimal performance. • At natural pH, 1%-FePc/UPCN photocatalyst showed the highest Photo-Fenton performance. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) ZnS-SnS 2 porous nanosheets are designed as clean and low cost photocatalysts for water splitting. The composites successfully combine high photoelectron reduction potential of ZnS with the sufficient sunlight harvesting ability of SnS 2 . Moreover, SnS 2 acts as an effective electron transfer medium from ZnS to SnS 2 due to the construction of quasi-type II structure. This greatly promotes the transfer of electron-hole pairs and effectively inhibits their recombination. Especially, the unique porous nanosheets structure maintains them high specific surface area and countless reactive sites, which increases the reactants' contact area and facilitates the migration of carriers upon photocatalysis. This further suppresses the charge recombination and improves the photocatalysts' stability. As a result, an optimized specific surface area of 246.7 m 2  g −1 and photocatalytic H 2 generation rate of 536 μmol h −1 g −1 are achieved in the absence of a surfactant and co-catalyst, which is 10 times higher than ZnS and 17 times higher than SnS 2 . In addition, the porous nanosheets have fairly good photocatalytic stability and can be reused at least five cycles without obvious changes in activity and structure. This work successfully presents the potential of ZnS and SnS 2 -based photocatalyst for clean and low cost hydrogen production from water splitting. [ABSTRACT FROM AUTHOR]

A Zn-P bond oriented black phosphorus/CuInZnS S-scheme heterojunction was successfully constructed for tetracycline (TC) degradation and synergistic H 2 generation. An enhanced photocatalytic H 2 revolution rate of 2056.0 μmol/h/g was achieved with triethanolamine (TEOA) as the hole sacrifice agent, which was nearly two times higher than that of CuInZnS (CIZS) and 170 times that of black phosphorus (BP). To further improve the hole utilization rate and reduce the energy consumption, an appropriate amount of TC was added instead of TEOA, and an improved photocatalytic H 2 generation rate of 1921.2 μmol/g was obtained with the synergistic degradation of TC by 82%. The types of heterojunctions and the transfer process of carriers were investigated by the combination of Mott-Schottky curves, Ultraviolet photoelectron spectroscopy, UV–vis diffuser reflectance spectra, and density functional theory. The results showed that a S-scheme heterojunction is built in BP/CIZS, which maintained the high redox ability of electron-hole pairs based on the successful separation of carriers. In addition, the novel Zn-P bond provided a charge transport channel and catalytic reaction active center upon photocatalysis. The design and application of photocatalysts proposed in this work offered a new idea for the coordinated resolution of environmental purification and energy conversion problems. • Zn-P bond induced BP/CIZS heterojunction was designed for waste to hydrogen conversion. • The hybrid has richer reactive sites, enhanced charge transfer and sunlight response ability. • Enhanced water splitting activity is achieved by the assistance of tetracycline. • A systematic study of photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen production from wastewater is an effective strategy to alleviate the increasingly energy crisis. In this work, ultrathin Ti 3 C 2 T x decorated AgInZnS (AIZS-TiC) polysulfide was designed as an efficient photocatalyst for hydrogen production from tetracycline (TC) wastewater. Compared with pure AIZS, the AIZS-TiC exhibited an improved photocatalytic hydrogen production rate of 226 μmol/g/h with synergistic TC degradation. In addition, the hydrogen evaluation rate can achieve 1287 μmol/g/h under 300 W Xe light irradiation with triethanolamine as the hole sacrifice agent, which is more than three times that of pure AIZS. The systematic mechanism study indicated that the introduction of novel metalloid TiC effectively optimizes the morphology and energy band structure of AIZS. Furthermore, the matched work functions of two materials ensure the establishment of Schottky junction between AIZS and metalloid TiC, thereby enhancing the surface-active site and inter-facial charge transfer of the photocatalyst. These findings provide a valuable reference for the design and application of polysulfide and metalloid TiC in the field of photocatalytic waste to energy conversion. [Display omitted] • Ti 3 C 2 T x decorated AgInZnS was designed for waste to hydrogen conversion. • The hybrid has richer reactive sites, enhanced charge transfer and sunlight response ability. • Enhanced water splitting activity is achieved by the assistance of tetracycline. • A systematic study of photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ag-ZnO core-shell structure was obtained via a simple one-step solvothermal process. [•] The approach was simple, mild, low cost, reproducible and easy-to-handle. [•] The obvious enhancement of UV luminescent has been observed. [•] Effects of the calcining temperature to luminescence were investigated in detail. [Copyright &y& Elsevier]

• Fe-doped g-C 3 N 4 photo-Fenton catalyst was prepared by one-step thermal polymerization method of melamine and pig blood. • Fe-doped g-C 3 N 4 shows efficient photocatalytic degradation efficiencies in acidic and alkaline environment, respectively. • Fe-N bonds in Fe-doped g-C 3 N 4 not only expedited the reduction cycles of Fe2+/Fe3+, but also acted as active sites. [Display omitted] Inspired by animal blood as a biowaste rich in biological enzymes with molecular Fe–N centers, Fe doped g-C 3 N 4 (FCN) photocatalyst was successfully prepared by one-step thermal polymerization with pig blood and melamine to produce an efficient photocatalyst with Fe–N active sites for photo-Fenton degradation of tetracycline (TC) under visible light irradiation. The photocatalytic TC degradation results exhibited that FCN-1 sample possesses optimal photocatalytic degradation activity for TC (50 mg/L) in the presence of H 2 O 2 system and a broad range over pH adaptation. The optimum photo-Fenton degradation activities of TC (50 mg/L) under visible-light irradiation for FCN-1/H 2 O 2 system reach to 84.9% and 0.034 min−1 within 120 min under acidic conditions (pH = 3.1) and to 85% and 0.093 min−1 (first 20 min) in alkaline environment. Enhanced photocatalytic activity is mainly attributed to the positive roles of Fe-N bonds in FCN during the photo-Fenton process as follows: (i) improving the absorbance and separation efficiency in electron-hole pairs; (ii) accelerating the catalytic cycles between Fe2+/Fe3+ to produce more •OH in acidic condition; (iii) serving as active sites to boost the production of more photon-generated carriers in alkaline environment. Our work overcame the defect of low photocatalytic activity in photo-Fenton process under alkaline conditions, and provided a simple design idea for the low-cost synthesis of visible-light-driven photocatalyst with high efficiency applied to photo-Fenton reaction. [ABSTRACT FROM AUTHOR]

Designing photocatalysts with a broad reaction to sunlight is crucial for efficient clean energy conversion. However, most catalysts reported so far can only respond to UV and visible light for photocatalysis, neglecting the utilization of near-infrared light, which accounts for almost 50 % of sunlight. In this study, we obtained Au nanoparticles (NPs) decorated porous hollow SrTiO 3 material rich in oxygen defects using an acid etching-assisted hydrothermal method. The formation of a Schottky heterojunction between Au and SrTiO 3−x with matched Fermi levels enhances the electron transfer ability of SrTiO 3−x. Additionally, Au NPs exhibit two types of surface plasma resonance (SPR) effects at 480 nm (transverse SPR) and 800 nm (longitudinal SPR in the near-infrared region) by absorbing specific photons emitted by SrTiO 3−x. The "hot" electrons of the photoexcited SPR state can be further injected into the CB of SrTiO 3−x. Furthermore, the local electromagnetic field around the SPR-enhanced Au NPs effectively promotes the excitation and transfer kinetics of photoelectrons, allowing more "hot" electrons to participate in the photocatalytic reaction. Besides, the unique hollow porous structure of the catalyst ensures multiple reflections of sunlight within SrTiO 3−x. As a result, the hydrogen production efficiency of Au-SrTiO 3−x under near-infrared (NIR) and UV–vis-NIR light irradiation reaches 850 and 3206 μmol h−1g−1, with apparent quantum efficiency of 6.4 % and 7.2 % at 820 nm and 420 nm, respectively. The possible photocatalytic mechanism was proposed based on thorough systematic experimental analysis and theoretical calculations. [Display omitted] • Au NPs decorated porous hollow SrTiO 3 rich in oxygen defects was prepared. • A Schottky heterojunction was formed between Au and SrTiO 3−x. • Transverse SPR and longitudinal SPR in near infrared region have been created. • The hydrogen production efficiency of 850 μmol h−1g−1 with the AQE of 7.2 % was achieved under near infrared irradiation. • The possible photocatalytic mechanism was proposed by systematic experiments analysis and theoretical calculations. [ABSTRACT FROM AUTHOR]

The development of bifunctional reaction by combining CO 2 reduction with antibiotics degradation is of great significance. Designing bifunctional catalysts with excellent performance is the focus of scholars' research. In this paper, Co-doped BiOBr ultra-thin nanosheets exposing rich (102) active crystal faces were prepared by one-step hydrothermal method. Since Co2+ has a smaller radius than Bi3+, Co was successfully incorporated into the lattice of BiOBr, which changed the crystal structure of BiOBr and obtained thinner nanosheets with rich lattice defects. The Gibbs free energy of CO 2 reduction reaction was synergistically optimized by the combination of exposing (102) active crystal faces and introducing lattice defects. In addition, the addition of Co changed the band structure of BiOBr and improved the carrier separation ability, making Co-BiOBr be an excellent bi-functional photocatalyst for CO 2 reduction and co-degradation of tetracycline, realizing the synergistic process of environmental purification and energy conversion. This work provides theoretical and experimental reference for the rational design of bifunctional photocatalysts. • Co-doped BiOBr ultra-thin nanosheets with rich (102) active face was prepared. • Co atoms occupy part of Bi positions and form abundant lattice defects. • The band structure and Gibbs free energy of BiOBr are optimized. • A systematic study of photocatalytic mechanism is proposed. [ABSTRACT FROM AUTHOR]

Abstract: The crystal structure and microwave dielectric properties of (Zn1− x Co x )TiNb2O8 ceramics have been investigated. The results showed that the (Zn1− x Co x )TiNb2O8 ceramics contained two main phases: (Zn,Co)TiNb2O8 phase and (Zn,Co)0.17Nb0.33Ti0.5O2 phase. The microwave dielectric properties of the (Zn1− x Co x )TiNb2O8 ceramics were strongly affected by the change of crystal structure of each phase. The (Zn1− x Co x )TiNb2O8 (x =0.1, 0.2, 0.3, 0.4) ceramics were sintered at temperatures ranging from 1025 to 1125°C for 4h. With the increase of Co content, the amount of (Zn,Co)0.17Nb0.33Ti0.5O2 phase increased, resulting in the increase of the dielectric constant (εr ), decrease of the Q × f value and the temperature coefficient of resonant frequency (τf ) moving to the positive direction. The excellent microwave dielectric properties of εr =35.93, Q × f =35,125GHz, τf =0ppm/°C were obtained for the (Zn1− x Co x )TiNb2O8 ceramics (x =0.3) sintered at 1075°C for 4h. The relatively low sintering temperature (<1080°C) and high dielectric properties in microwave range make these ceramics promising for application in electronics. [Copyright &y& Elsevier]