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As a new type of non-metallic polymer semiconductor, graphite phase carbon nitride (g-C3N4) has the properties of easy synthesis, non-toxic and harmless, acid and alkali corrosion resistance, and good environmental affinity. The unique layered structure gives it a high specific surface area, and the moderate band gap width gives it better photocatalytic performance. However, pure phase g-C3N4 has the disadvantages of small specific surface area, insufficient active site, rapid carrier recombination and weak redox ability, which restrict its effective application in the field of photocatalysis. Studies have shown that the structural regulation of g-C3N4 using a template induction process can effectively solve the above problems. In this paper, the template methods commonly used for the preparation of graphite phase carbon nitride (hard template method, soft template method and biological template method) are reviewed, the progress of multiphase composite process is discussed, and the application of g-C3N4 based materials in photocatalytic degradation, CO2 conversion and hydrogen produc- tion are summarized. [ABSTRACT FROM AUTHOR]

Tn this paper, N-CT)s and N-CT)s-X@Nb9 ()5-AMMC nano mate rials modified with different contents of N-CT)s have been successfully prepared by a simple hydrothermal method. N-CT)s-X@ Nb ()5-AMMC was characterized by XRT), SEM, TEM, FT-TR, XPS, UV-vis DRS and so on, and the results indicate that the band gap of Nb()5-AMMC is narrowed after N-CT)s modification, and the absorption band edge of the sample shows redshift and wider light absorption range, which is conducive to improving the photocatalytic performance. Tn addition, N-CT)s reduces the resistance of electron transport, which is conducive to the transfer of photogenerated electrons to the N-CT)s structure. At the same time, the migration and separation efficiency of photogenerated carriers are improved, which is conducive to the photocatalytic reaction. Compared with pure Nb ()5-AMMC. N-CT)s-X@ Nb O-AMMC has improved photocatalytic degradation performance of TC-HC1 under visible light, in which N-CT)s-l ©NbO-AMMC has the highest degradation efficiency. The degradation rate of N-CT)s-1 @ Nb ()5-AMMC for TC-HC1 reaches 63.2% within 1 h, which is 1.59 times of pure Nb ()5-AMMC. [ABSTRACT FROM AUTHOR]

Semi conduct or-based photocataiytic technology was selected as a "green" sustain able solution for environmental remediation and energy storage with solar energy. Tn this paper, the advantages and limitations of g-C-3 N-i, as well as the advantages and disadvantages of S-type semiconductors are first introduced, then the electronic structure and photocataiytic properties of g-C3 Ni-based S-type heterojunction photocataiytic materials are introduced. Then the strategies with which to improve the photocataiytic performance of S-type heterojunction photocataiytic materials based on different types of g-C3 N.-i are reviewed, and some of their applications are reviewed. Finally, this review gives the challenges and future development trends of S-heterojunction based on g-C3 N-i, which is expected to provide important references for the development and practical application of g-C3 Ni-based S-heterojunction photocataiytic materials. [ABSTRACT FROM AUTHOR]

Pollution of water resources is seriously endangering human health. Bismuth-based photocatalytic materials also show great potential in controlling organic pollution, with the advantages of green, efficient, clean and low cost. This paper briefly introduces the research progress of various bismuth-based photocatalytic materials in the degradation of organic wastewater, summarizes the modification methods of various bismuth-based photocatalysts and the degradation effects of various organic pollutants, and analyzes the factors affecting the efficiency of bismuth-based photocatalytic materials in the degradation of organic compounds in water. The future development of photocatalysis in the degradation of organic wastewater was also explored, and several proposals for the development of bismuth-based photocatalysis materials were presented. [ABSTRACT FROM AUTHOR]

Photocatalytic reaction has important applications in the fields of degradation of harmful pollutants, conversion of greenhouse gases, production of hydrogen, elimination of harmful bacteria and so on. Tn recent years, ferroelectric materials with spontaneous polarization have been considered as a new candidate. Their spontaneous polarization can produce a built-in electric field and provide a driving force for the transmission of photogenerated carriers. This characteristic is expected to solve the thorny problem encountered in the field of photo catalysis, the recombination of electron hole pairs. Because of this characteristic, the research on the photocatalytic properties of ferroelectric materials mainly focuses on reducing the recombination of holes and electrons. But in fact, to improve the photocatalytic efficiency, we need to consider the whole catalytic process, including three key stages, photon absorption, separation and migration of photogenerated electron holes and terminal reaction. Focusing on the above three stages of photocatalytic process, this paper sorts out the typical a-chi eve merits in recent years, and combs the effective means to improve the catalytic performance of ferroelectric materials in different stages of photocatalysis. Tt is hoped that our summary can provide a useful reference for the follow-up research work. [ABSTRACT FROM AUTHOR]

In this paper, four perovskite type composite metal oxide lanthanum co bait ate catalysts with different ratios are prepared by hydrothermal synthesis. The ratios of La(NO3)2, Co(NO3)2 and citric acid are 1 :1 :3, 1 :1 : 4, 1 : 1 : 5 and 1 : 1 : 6, respectively. The structure and properties of the catalyst are characterized by XRD, SEM and TEM. Acid red B is used as the research object. Xenon lamp is used to simulate the degradation of acid red B dye wastewater under sunlight. The results show that the degradation rates of acid red B by the four catalysts are more than 80%, while the LaCoOs catalyst with the ratio of 1 :1 : 6 has the best degradation effect on acid red B, and the degradation rate reaches 88.52% after visible light irradiation at 20 °C for 1 h. Tt is found that lanthanum cobaltate catalyst with large specific surface area has the best photocatalytic degradation effect on acid red B, on the contrary, the degradation effect of lanthanum cobalt ate catalyst with small specific surface area is poor. The degradation of acid red B by four ratios of lanthanum cobaltate catalysts accords with the first-order reaction kinetic equation. [ABSTRACT FROM AUTHOR]

Due to its wide band gap, the semiconductor ZnO has poor visible light photocatalytic activity. In this paper, N-doping, carbon coating, noble metal modification and semiconductor coupling are used to improve the visible light phorncatalytic activity of ZnO. The efficiency of photocatalytic degradation of organic pollutants is compared by different materials with Rhodamine R as degradation pollutant mode l. The results show that the visible light absorption of N-ZnO photocatalyst prepared by hydrothermal method is enhanced in contrast to that of pure ZnO. The C@ N-ZnO sample prepared by hydrothermal carbonation of glucose exhibits strong adsorption capacity for organic pollutants. The Au/C@N-ZnO sample obtained by precious metal de position an d CdS/ Au/C@N-ZnO prepared by semiconductor coupling show the further enhanced absorption capacity in the visible light region. Photoluminescence and transient fluorescence spectra demonstrate that oxygen defects, precious metal deposition, and semiconductor coupling can effectively improve the separation efficiency of photogene rated carriers, thereby improving the photodegradation efficiency of the photocatalysts. The photocatalytic mechanism is also discussed. The reaction rate for Rhodamine R degradation over CdS/Au/C@ N-ZnO is 6.7 times of pure ZnO. [ABSTRACT FROM AUTHOR]

TiO2/Bu2WO6 heterojunction is one of the most potential visible light responsive semiconductor photocatalysts. Tn this paper, TiO2/Bi2WO6 composites with heterogeneous structure are synthesized by hydrothermal method with TiO2 nanobelts rich in defects as the matrix. The effects of matrix surface defects and Biv W()b loading on the microstructure and properties of TiO2/Bi2WO6 composites are analyzed by XRT)，SEM and UV-Vis techniques. The results show that the degradation rate of organic pollutant Rh B in TiO2/Bi2WO6 composites can be increased about 50% by introducing defects on the surface of the matrix. When the loading of Bi,W(X is 0J2? the degradation rates of Rh R? MB and TC-HC1 are 99.3%, 99.7% and 87.7% respectively after irradiation for 6 min，3() min and 1 5 min. [ABSTRACT FROM AUTHOR]

Solar photocatalysis technology is widely applied to control environmental pollution. In the field of photocatalysis, silver phosphate (Ag3PO4) has gradually become a research hotspot for its high quantum efficiency, non-toxicity, and small band gap. However, in the photocatalytic process, pure Ag3PO4 is prone to photo-corrosion with poor stability, which severely limits its practical application. In this present paper, based on type II and 2-scheme, the type, preparation method, structural characteristics and photocatalytic mechanism of Ag3PO4-based heterojunction photocatalytic materials are mainly introduced. The latest progress in the degradation of organic pollutants by Ag3PO4-based heterojunction photocatalytic materials in recent years is also reviewed. Finally, the further researches on Ag3PO4-based heterojunction photocatalytic materials are prospected. [ABSTRACT FROM AUTHOR]

Is a new type of environmental treatment technology, TiO2 photowtalysis technology can be applied to sewage treatment, air purification and other fields. Ti01 has the advantages of non-toxic, harmless, economical, high photocatalytic efficiency and no secondary pollution, but the catalytic efficiency is not high. The efficiency of the photocatalyst can be effectively improved by loading and doping. In this paper, using TROT as the titanium source, wrbonized glucose as the carbon source, and refined diatomite as the carrier, TiO2, -C@.diatom ite composite phot0catalyst was prepared by the sol-gel method and the in-situcarbonizat ion method. The ex perimental results show that the best preparation process was Cloading of 20%, loading method was first load ing C and then loading TiO2, and calcination method was calcination in isolation of air. The degradation rate of the composite photocatalyst obtained was 96.4%. after recovered and continued to degrade 5 times, the degradation rate of the composite phot0catalyst obtained was 86.:3 % . [ABSTRACT FROM AUTHOR]

In this paper, graphene oxide(G0)was firstly prepared from graphite by a modified Hummers method, GO/TiO2 carrier were prepared by sol-gel method using TBOT as the Ti，and then magnetic photocatalyst GO/TiO2/Fe3O3 composites were synthesized by hydrothermal method. The composition, morphology and structure of the catalysts were analyzed by FTTR，XRT), SEM and DR S. The catalysts were applied to pho to catalytic degradation of methyl orange (MO) solution，and investigated the effect of different catalysts and the dosage of composite catalysis. The experimental results showed that GO/TiO2/Fe3O3，had high photo catalytic activity and good recycling and regeneration ability，the degradation rate of 0.06 g magnetic composite degrading 50 mL 10 mg/L MO solution reached 95.4% within 120 min，and degradation process obeys the first order kinetic model. [ABSTRACT FROM AUTHOR]

In this paper, a photocatalytic material of N-doped Cu2O was prepared by reducing Cu2+ with hydrazine hydrate. And it was characterized by UV-vis DRS, PL, XRD, XPS and FT-IR. The results indicate that the absorption spectrum of N-doped Cu2O was blue-shifted, which had slightly wider band gap than pure Cu2O. The photoluminescence peak produced by light excitation was weaker, which indicated that the photogenerated electron-hole pair produced in the photocatalysis reaction was easier to separate, so that the photocatalytic reaction could be carried out more efficiently. The doping of N inhibited the growth of Cu2O crystallites, which affected the photocatalytic performance to some extent by changing its structural characteristics. Furthermore, the N-doped Cu2O samples had excellent visible light photocatalytic activity in the photodegradation experiments of methyl orange simulated wastewate [ABSTRACT FROM AUTHOR]

In recent years, perovskite-type compounds have become a hot research topic in the field of photocatalysis due to their unique structures. Barium titanate (SrTiO3) is a typical perovskite-type composite oxide with high stability, non-toxicity, high carrier mobility and high photocatalytic activity. It has low-resistance electron transport structure for semiconductors and the high-efficiency redox capability of small molecules is a photocatalytic material with great development potential and application prospects. In this paper, the structure, preparation method and photocatalytic mechanism of SrTiO3 materials we re introduced, and the modification of SrTiO3 in the field of photocatalysis was reviewed. Finally, based on the existing research results, a brief analysis of the future development trend of SrTiO3 photocatalytic materials would help researchers to make further breakthroughs. [ABSTRACT FROM AUTHOR]

In this paper, zinc chloride, sodium hydroxide, aluminum nitrate nonahydrate and yttrium nitrate hexahydrate were used as raw materials. Al-Y co-doped ZnO nanosheets were prepared by low temperature water bath method. At the same time, the prepared samples were characterized by scanning electron microscopy, X-ray diffraction, ultraviolet-visible diffuse reflection, etc. The effects of different doping contents of Al and Y elements on the photocatalytic performance were studied by degradation of methylene blue, which was used as colored pollutant. Results show that when the doping contents of Al and Y element were 3%, the surface state of ZnO was obviously improved and more hydroxyl radicals were formed. At the same time, the concentration of photogenerated hole pairs was increased and the photocatalytic performance of ZnO was improved obviously. After 1 h of UV lamp irradiation, the degradation rate of the lamp was 94.63%. And after 5 cycles, the degradation rate could still reach more than 85%, showing that Al-Y co-doped ZnO nanosheets had good photocatalytic performance and cycle stability. [ABSTRACT FROM AUTHOR]

In this paper, in order to effectively improve the efficiency of the light absorption of catalysts and catalytic efficiency, carbon quantum dots (CQI)s) were introduced into titanium-based metal organic framework material MIL-125, aiming to organically combine the advantages of high specific surface area and more catalytic sites of MOFs with the excellent optical properties of CQDs, and achieve synergistic effect. The morphology, structure and photoelectric properties of the composite photocatalyst were characterized. Its catalytic properties in the visible light catalytic degradation of organic dyes were systematically studied and the way of the introduction of CQDs effects on structure and performance of composite catalyst was explored. [ABSTRACT FROM AUTHOR]

Recently there have been frequent water pollution incidents all over the world. Water pollution control has been grim, and people's health has been seriously threatened. Tt's hard to degrade sewage of complex comporients and low biodegradability by conventional water treatment process, which seriously affects the safety of water's usage. Titanium dioxide (TiO2) photocatalysis is an environment-friendly and energy-saving technology? and has been widely studied in wastewater treatment. However the utilization of TiO2 powder in suspension has the disadvantages of easy 1 eachirig? difficult recovery and easy agglomeration. The aim of this paper is to provide a thorough review of the types of supported TiO2 system ? including its supporting skeleton and loading methods? arid the application of the supported TiO2 photocatalysis in wastewater treatment has also been described. The prospect the development of supported TiOv was also proposed. [ABSTRACT FROM AUTHOR]

In this paper, ZnO nanorods, NiO nanosheets and NiO@ZnO nanocomposite with uniform size and good reproducibility were prepared on carbon cloth by electrochemical method. The morphology and crystal structure were characterized by scanning electron microscopy and X-ray diffraction. The photocatalytic performance of ZnO@NiO nano-heterostructure is evaluated by the photodegradation of rhodamine B under the ultraviolet light, and the result indicates that the NiO@ZnO nano-heterostructure exhibits more excellent photocatalytic property. And the photocurrent response of NiO@ZnO structure is superior to pure ZnO nanorods and NiO nanosheets. These good optoelectronic properties are attributed to the formation of a p-n junction between ZnO and NiO to facilitate the separation of photo-generated carriers. [ABSTRACT FROM AUTHOR]

In this paper, melamine was selected as the precursor to prepare g-C3N4 through calcination method. The g-C3N4/CuPc composites were synthesized by ultrasonic method，then the prepared materials were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction spectra (XRD) and UV-visible absorption spectrum analysis (DRS). In this photocatalytic degradation experiments, 2,3-dichlorophenol was chosen as the target contaminant to investigate the photocatalytic active of the prepared materials under the 500 W xenon lamp irradiation. Various experimental parameters including the mass ratio of CuPc and g-C3N4 in g-C3N4/CuPc composites, the dosage, and the initial concentration of 2,3-dichlorophenol were optimized. In addition, the kinetics of the photocatalytic reaction was also discussed. The experimental results show that the degradation efficiency of 2,3-dichlorophenol can reach 92% after 240 min irradiation. The reaction was conformed to follow the first-order reaction kinetics model. ?OH plays the main role in the photocatalytic process of 2,3-dichlorophenol. [ABSTRACT FROM AUTHOR]

Two kind of WO3 nanoparticles with different crystalline phase were synthesized by the hydrothermal method. The microstructures and surface topography of the samples were investigated by XRD and SEM, respectively. Meanwhile,its photo catalytic performance to methyl orange(MO) and methylene blue(MB) was researched by using spectrophotometer. The research focused on the different photocatalytic performance showed by different crystalline phases WO3 with the same morphology. Also, the different photocatalytic properties of WO3 nanoparticles to MO and MB were studied. The results revealed that the different phase WO3 showed different photocatalytic properties to the same wastewater clearly and the same phase WO3 showed the different degradation rate to the different wastewater. The reason and mechanism for the differences have been analyzed in this paper. [ABSTRACT FROM AUTHOR]