Visible Light Photocatalytic Activity Research Articles

V2C MXene–modified g-C3N4 for enhanced visible-light photocatalytic activity

Increasing the efficiency of charge transfer and separation efficiency of photogenerated carriers are still the main challenges in the field of semiconductor-based photocatalysts. Herein, we synthesized g-C3N4@V2C MXene photocatalyst by modifying g-C3N4 using V2C MXene. The prepared photocatalyst exhibited outstanding photocatalytic performance under visible light. The degradation efficiency of methyl orange by g-C3N4@V2C MXene photocatalyst was as high as 94.5%, which is 1.56 times higher than that by g-C3N4. This was attributed to the V2C MXene inhibiting the rapid recombination of photogenerated carriers and facilitating rapid transfer of photogenerated electrons (e−) from g-C3N4 to MXene. Moreover, g-C3N4@V2C MXene photocatalyst showed good cycling stability. The photocatalytic performance was higher than 85% after three cycles. Experiments to capture free radicals revealed that superoxide radicals (·O2−) are the main contributors to the photocatalytic activity. Thus, the proposed g-C3N4@V2C MXene photocatalyst is a promising visible-light catalyst.

Well-designed glucose precursor carbon/g-C3N4 nanocomposite for enhanced visible light photocatalytic CO2 reduction activity

Fabrication of glucose precursor carbon-doped g-C3N4 nanocomposite (C/g-C3N4) for enhancing photocatalytic CO2 reduction into syngas (CO, CH4) has been investigated. The samples were successfully synthesized via a two-step thermal treatment and tested in a fixed bed reactor under visible light. The 0.2 % glucose precursor carbon-doped over g-C3N4 photocatalyst has demonstrated excellent activity in converting CO2 to CO and CH4 under visible light. The main product yield, CO of 898.9 μmol g-cat−1 was produced over 0.2 % C/g-C3N4, which is 4.6 folds the amount of CO obtained over the g-C3N4 (196.8 μmol g-cat−1). The XPS results confirmed the formation of a C-O-C bond between carbon and g-C3N4, resulting in a strong interaction between carbon and g-C3N4. Carbon-doped g-C3N4 possesses a narrow energy band and the ability to effectively absorb solar light, which enables efficient transportation of electrons generated by photon excitation. Possible reaction mechanisms for photoreduction of CO2 over carbon-doped g-C3N4 photocatalyst were proposed in order to understand the movement of electrons and holes. This work provides a simple method for designing highly efficient carbon-based photocatalysts for potential application in photocatalytic CO2 reduction using solar energy.

Nitrogen-doped porous carbon TiO2 produced by thermolysis of MIL-125-NH2 under an inert atmosphere for enhanced visible light photocatalytic activity

Metal-organic frameworks have gained significant attention as precursors for the synthesis of functional materials with tailored properties. In this study, we present the synthesis and characterization of nitrogen-doped porous carbon TiO2 (N-C/TiO2) by thermolysis of MIL-125-NH2. The effect of calcination temperature (ranging from 300 to 900°C) and atmospheric conditions on the phase transition, elemental composition and morphological structure is thoroughly investigated. Through X-ray diffraction (XRD) analysis, we identified the formation of the rutile phase in the N-C/TiO2 nanoporous structure, which leads to the creation of oxygen vacancies and metal defects. Interestingly, the orthorhombic shape of MIL-125-NH2 is retained in the final N-C/TiO2 product, indicating the robustness of the conversion process. The UV-Vis diffuse reflectance (UV-Vis) and photoluminescence (PL) analysis demonstrated that the phase transition results in a narrowed band gap energy and reduced recombination of photogenerated electron-hole pairs. The photocatalytic activity of the synthesized N-C/TiO2 is evaluated by the degradation of methylene blue (MB) dye under visible light irradiation. Our results revealed that superoxide radicals are the primary species responsible for the photocatalytic reaction. Furthermore, the N-C/TiO2 photocatalyst exhibits excellent stability and recyclability for five consecutive photocatalytic cycles. Overall, this study provides novel insights into the synthesis, characterization and photocatalytic activity of N-C/TiO2 material derived from MIL-125-NH2, emphasizing the significance of calcination temperature and atmospheric conditions. The developed N-C/TiO2 poses great potential for various environmental and energy applications where enhanced visible light photocatalytic activity is desired.

Fabricating BiOCl Nanoflake/FeOCl Nanospindle Heterostructures for Efficient Visible-Light Photocatalysis.

Fabricating heterostructures with abundant interfaces and delicate nanoarchitectures is an attractive approach for optimizing photocatalysts. Herein, we report the facile synthesis of BiOCl nanoflake/FeOCl nanospindle heterostructures through a solution chemistry method at room temperature. Characterizations, including XRD, SEM, TEM, EDS, and XPS, were employed to investigate the synthesized materials. The results demonstrate that the in situ reaction between the Bi precursors and the surface Cl- of FeOCl enabled the bounded nucleation and growth of BiOCl on the surface of FeOCl nanospindles. Stable interfacial structures were established between BiOCl nanoflakes and FeOCl nanospindles using Cl- as the bridge. Regulating the Bi-to-Fe ratios allowed for the optimization of the BiOCl/FeOCl interface, thereby facilitating the separation of photogenerated carriers and accelerating the photocatalytic degradation of RhB. The BiOCl/FeOCl heterostructures with an optimal composition of 15% BiOCl exhibited ~90 times higher visible-light photocatalytic activity than FeOCl. Based on an analysis of the band structures and reactive oxygen species, we propose an S-scheme mechanism to elucidate the significantly enhanced photocatalytic performance observed in the BiOCl/FeOCl heterostructures.

Enhanced visible-light photocatalytic activity of FeVO4/Bi2WO6 heterojunction via Z-scheme charge-transfer mechanism

The design and construction of a Z-scheme heterojunction, aiming to strengthen its redox ability for photocatalytic applications, is challenging. In this study, a series of x mol%-FeVO4/Bi2WO6 heterostructures were fabricated. FeVO4 content was tuned for enhanced organic pollutants photodegradation. The 2.5 mol%-FeVO4/Bi2WO6 photocatalyst exhibited superior photodegradation efficiency with high recyclability and stability for bisphenol A and methylene blue, which was 3.3 and 2.6 times faster than that of Bi2WO6, respectively. Moreover, the fabricated photocatalyst showed remarkable selectivity toward methylene blue as compared to that toward brilliant green and methyl orange. The photo-efficacy was enhanced owing to the close interfacial contact between Bi2WO6 and FeVO4 nanoparticles, resulting in a Z-scheme FeVO4/Bi2WO6 heterojunction, which enabled efficient charge transfer imparting strong reducing ability to the electrons for the reduction of O2 to •O2−, and subsequent production of H2O2 and •OH. This work highlights a potential photocatalyst for photodegradation of environmental pollutants.

Improved charge transfer and enhanced visible light photocatalytic activity of Bi2O3@Fe-MOF for degradation of Rhodamine B and Triclopyr

ObjectivesMetal organic frameworks (MOFs) composites, integrated with metal oxides augment the inherent characteristics of the original frameworks. Present study aims to investigate and assess the potential of Bi2O3@Fe-MOF composites in efficient photocatalytic degradation of two distinct organic pollutants, namely Rhodamine B (RhB) dye and Triclopyr (TC) pesticide. MethodsA series of Bi2O3@Fe-MOF was synthesized by changing the Fe: Bi molar ratios and following the solvothermal method. Fabricated materials were analyzed primarily for crystalline arrangements, morphology features and chemical compositions, band gap energies, functional moieties, recombination of charge carriers, and surface charge. These assessments were carried out with the different advanced techniques including XRD, FTIR, FESEM and EDX, UV–Vis DRS, PL, and Zeta potential analysis. The synthesized composites were studied for their ability in photocatalytic breakdown of RhB and TC under visible light irradiation. The pseudo first order kinetic model is implemented to study the degradation kinetics of the pollutants. Trapping experiments were performed to determine the reactive species responsible for the degradation reaction. Results and conclusionsThe study showed that the crystalline nature, morphology, and optical absorbance of the prepared composites changed with Fe:Bi molar ratio. The degradation efficiency of Bi2O3@Fe-MOF-3 for RhB and TC was 91.79% and 88.42%, respectively, in 120 min, making it the most effective synthesized material. The pseudo-first-order kinetic model was in good agreement with the experimental data. The trapping experiments revealed that hydroxyl radicals (OH) were the main contributors to the degradation reaction.This study concluded that Bi2O3@Fe-MOF composites are promising photocatalysts for the degradation of organic pollutants. The highest photocatalytic performance of Bi2O3@Fe-MOF-3 is attributed to the connected interfaces between Bi2O3 and Fe-MOF phases, which facilitate effective charge injections and separation.

Efficient charge carrier separation over carbon-rich graphitic carbon nitride for remarkably improved photocatalytic performance in emerging organic micropollutant degradation and H2 production

Graphitic carbon nitride (g-C3N4) shows great potentials in visible-light-driven catalytic oxidation of organic micropollutants to harmless products and reduction of water to H2 but suffers from drawback of sluggish charge carrier separation and transfer dynamics. To overcome this drawback, here a novel point defect engineering strategy, by a nicotinic acid or barbituric acid-assisted supramolecule self-assembly of dicyandiamide followed by thermal polymerization, is designed to prepare pyridine unit-incorporated g-C3N4 (CPyr-CNx) and carbon atom self-doped g-C3N4 (C-CNx). The strategy leads to well-regulated chemical structures of CPyr-CNx and C-CNx and thus the precisely controlled electronic structures. The CPyr-CNx and C-CNx both exhibit remarkably improved visible-light photocatalytic activity in degradation of emerging organic micropollutants (methylparaben, acetaminophen and bisphenol A) and water-splitting to H2 production in comparison of bulk g-C3N4 and carbon-rich g-C3N4 prepared by a direct thermal copolymerization of nicotinic acid or barbituric acid with dicyandiamide, and their photocatalytic redox activity depends on carbon doping level. Experimental results combined with theoretical simulations reveal that the superior photocatalytic redox performance of CPyr-CNx and C-CNx is mainly dominated by the significantly boosted charge carrier separation and transfer dynamics driven by carbon doping induced-local electric field and -midgap states, which finally generates abundant reactive oxidation species including •O2− anion radicals, •OH radicals and 1O2 for the deep oxidation of target organic micropollutants to significantly reduce their ecotoxicity; additionally, such efficient charge carrier separation and transfer also favors high mobility for free electron-involved photocatalytic H2 evolution reaction.

Visible-LEDs-induced enhanced photocatalytic and antibacterial activity of BiVO4-based green photocatalysts decorated with silver and graphene

Bismuth vanadate (BiVO4) is an attractive compound because of its visible light photocatalytic activity with a narrow energy gap of less than 2.4 eV. In addition, it has favorable band edge positions and is stable in an aqueous environment. Its photocatalytic activity can be translated for potential use for degradation of organic matter. To assess this activity, BiVO4 combined with graphene (N-G/BiVO4), silver (Ag/BiVO4), or both of them (N-G/Ag/BiVO4) were synthesized. These nanostructures (NSs) were characterized using physicochemical analyses. The NSs were tested for their capabilities to photodegrade crystal violet and inactivate bacteria. Results showed that N-G/Ag/BV exhibited the highest activity for degrading crystal violet, reaching 100 % of photodegradation within 60 min of light exposure, while N-G/BiVO4, BiVO4 and Ag/BiVO4 achieved 81, 89 and 95 % within 180 min, respectively. In the case of bacterial inactivation, the Ag/BiVO4 NS completely photoinactivated E. coli within 60 min. The main oxidative species acting in the E. coli photoinactivation and CV photodegradation over the Ag/BiVO4 and N-G/AgBiVO4 NSs were identified as •O2– and h+. Also, the chemical stability and effective re-use of the photocatalysts were evaluated. In conclusion, the Ag/BV and N-G/Ag/BV catalysts possess high stability, making them potential candidates for wastewater treatment.

Visible-light activation of carbon-supported BiVO4 photocatalysts

Bismuth vanadate (BiVO4) has gained attention for several applications, including photocatalysis applied to water purification technologies. This applies to the most stable BiVO4 polymorph (monoclinic scheelite), exhibiting photocatalytic activity under visible-light irradiation. However, this semiconductor presents some limitations, namely the cost and low adsorption capacity for organic pollutants. Finding green chemical strategies aiming at a more sustainable use of this semiconductor is the subject of the present research. By the hydrothermal carbonization of κ-carrageenan, a biopolymer extracted from red seaweeds, we describe the preparation of monoclinic BiVO4 supported on carbon spheres. These hybrid materials show visible-light photocatalytic activity to remove tetracycline (TC) in water through a hydroxyl radical mechanism. The hybrid photocatalysts feature adequate wavelength range for photon harvesting, good adsorption capacity, durability, and the ability to reuse in subsequent catalytic steps, thus making them less costly and more sustainable.

Controllable Synthesis, Photocatalytic Property, and Mechanism of a Novel POM-Based Direct Z-Scheme Nano-Heterojunction α-Fe2O3/P2Mo18.

In order to improve photocatalytic activity and maximize solar energy use, a new composite material Fe2O3/P2Mo18 was prepared by combining polyoxometalates (P2Mo18) with Fe2O3 nanosheets. FT-IR, XRD, XPS, SEM, TEM, UV-vis, EIS, and PL were used to characterize the composite material, and nano-Fe2O3 of different sizes and morphologies with a controllable absorption range was prepared by adjusting the reaction time, and, when combined with P2Mo18, a composite photocatalyst with efficient visible light response and photocatalytic activity was constructed. The EIS, Bode, and PL spectra analysis results show that the Fe2O3/P2Mo18 composite material has outstanding interfacial charge transfer efficiency and potential photocatalytic application possibilities. Model reactions of methylene blue (MB) and Cr (VI) photodegradation were used to evaluate the redox activity of Fe2O3/P2Mo18 composites under simulated visible light. The photocatalytic degradation rate was as high as 98.98% for MB and 96.86% for Cr (VI) when the composite ratio was Fe2O3/P2Mo18-5%. This research opens up a new avenue for the development of high-performance photocatalysts.

Study on highly efficient p-n heterojunction Bi2MoO6/Cu2O: Synthesis, characterization and visible-light photocatalytic activity toward antibiotics degradation

Water pollution has reached alarming levels due to the overuse of antibiotics, and photocatalysis is considered to be a green and efficient degradation technology for the treatment of water pollution caused by antibiotics. In this paper, a series of p-n heterojunction Bi2MoO6/Cu2O composite photocatalysts were synthesized by hydrothermal method. The samples were characterized by XRD, SEM, XPS, UV–Vis-DRS, PL, and EIS. The photocatalytic activities of the photocatalysts were analyzed based on the degradation of two antibiotics under visible light illumination. Results showed a removal rate of 88% and 94% for chlortetracycline (CTC) and tetracycline (TC), respectively. The corresponding first-order kinetic curves indicated that the reaction rates were 4.2 and 7.9 times higher than those of the Bi2MoO6 and Cu2O monomers. The enhanced removal efficiency of antibiotics is ascribed to the improved light absorption and electron-hole pair transport channels, facilitated by the formation of p-n heterojunction within the catalyst. Further, a possible degradation mechanism was proposed. Finally, the intermediate products were analyzed using liquid chromatography-mass spectrometry (LC-MS), and a possible photocatalytic degradation pathway of CTC was proposed. Based on the present study and experimental observations, Bi2MoO6/Cu2O as a visible-light-driven photocatalyst is suggested to be a promising candidate for the removal of antibiotics.

In situ synthesis of core-shell like BiVO4/BiOCl heterojunction with excellent visible-light photocatalytic activity

A well-integrated core-shell like BiVO4/BiOCl heterojunction was synthesized by a two-step solvothermal method. BiVO4 nanosheets shell were in situ synthesized on the surface of BiOCl microsphere core. Compared with the pure BiOCl, it had a larger BET surface area, stronger visible-light absorption and faster transfer of photocarriers. It had a much better photocatalytic performance than the pure BiVO4, which was owing to the enlarged surface area, enhanced visible-light absorption and photocarriers’ separation and transfer. The photogenerated electrons and holes of the BiVO4/BiOCl heterojunction transferred through a Z-scheme route, which made it had a better photocatalytic performance than that of the II type one.

PREPARATION AND PHOTOCATALYTIC PERFORMANCE OF AG3PO4/MOS2 COMPOSITE PHOTOCATALYST

Ag3PO4 and MoS2 semiconductor materials were synthesized by hydrothermal method. The composite materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS), and UV–vis diffuse reflectance spectroscopy (UV–VIS DRS), and the photocatalytic degradation of organic dyes by rhodamine B was studied. The results showed that: Ag3PO4/MoS2 composite photocatalyst is formed by using MoS2 microspheres as the matrix and Ag3PO4 nanoparticles coated on its surface or embedded in its lamellar structure. When the molar fraction of Ag3PO4 in the composite product is 75%, the composite photocatalyst has better light absorption capacity and lower photogenerated carrier recombination rate (optical band gap is 1.24 eV), and shows better visible light photocatalytic degradation activity in the photocatalytic degradation of RhB experiment, the catalytic degradation rate is as high as 95.0%. At the same time, the degradation mechanism showed that H+ and O2− were the main active substances for RhB degradation. The photocatalyst has excellent performance and simple preparation method. It has broad application prospects in the field of photocatalysis.

Synthesis and characterization of enhanced visible light-driven C-doped ZnO-2D GO/g-C3N4 heterojunction photocatalyst

Well-designed 2D graphene oxide-modified polymeric graphitic carbon nitride composite nanosheets (GO/g-C3N4) as desirable sensitizers and catalytic substrates for optimising the visible light-driven photocatalytic performance of ZnO-based photocatalysts have been investigated. Herein, 2D GO/g-C3N4 composite nanosheets are first developed by ultrasonic and hydrothermal methods, and then coupled with ZnO nanoparticles to prepare a series of ternary GO/g-C3N4-ZnO heterojunction composites with vary GO loading concentrations. Characterization of the photocatalysts was carried out by SEM, TEM, XPS, XRD, DRS, photoluminescence (PL) spectroscopy; evaluation of the visible light photocatalytic activity was performed by degrading an aqueous methylene blue (MB) solution. XPS studies showed that the formation of a ZnC bond in 15 % GO/g-C3N4-ZnO is due to the replacement of oxygen by carbon, indicating the construction of a hybrid heterojunction composed of C-doped ZnO and visible light sensitive GO/g-C3N4 composite nanosheets. The photodegradation performance of 15 % GO/g-C3N4-ZnO is 5.3, 2.9, and 2.2 times higher than that of pure ZnO, g-C3N4, and g-C3N4-ZnO, respectively. Due to the increase of GO loading in GO/g-C3N4 composite nanosheets, some characteristics of efficient visible light photocatalysis, such as a wider light absorption range, fluorescence quenching in the PL spectrum, excellent optical response in photocurrent measurement, and good stability，were confirmed and can be attributed to the electronic interaction between heterostructures and the effective transfer of photogenerated electrons in these ternary nanocomposites. This work may provide a new promising pathway for the construction of easily prepared 2D GO/g-C3N4 hybrid-modified nanocomposites, which is a hopeful material for wastewater control.

Using adatoms to tune the band structures of Cu2O surfaces for photocatalytic applications

Cuprous oxide (Cu2O) is a highly promising semiconductor with exceptional visible-light photocatalytic activity, and its nanoparticles have significant implications for promoting the Net Zero and Green Energy Economy due to low cost, ease of synthesis, and impressive performance. However, the photocatalytic effectiveness of Cu2O is heavily determined by the adsorbed species and crystal facets, both of which are crucial to the facet engineering of Cu2O. Here we applied first-principles calculations to investigate the geometric and electronic structures, as well as the thermodynamic stabilities, of Cu2O (100), (110), and (111) surfaces upon decoration with H, OH, Na, Cl, and Br units, respectively. We find that H, OH, and halogen atoms are efficient in stabilizing the Cu2O surface. The H atom is an excellent donor regardless of the surface orientation, whereas the roles of Br and Cl atoms as either donors or acceptors depend on specific surface conditions. Notably, the coverage conditions are essential in shaping the electronic properties of the (110) surface, on which the half-coverage OH-terminated surface manifests a suitable band structure facilitating the separation of the electron/hole pairs, thereby enhancing the photocatalytic efficiency. Accordingly, our calculations confirm that these species usually within the synthesis environment also have the ability to engage in the reaction and significantly alter the inherent facet-dependence of electronic structures in Cu2O crystals. These findings can help to elucidate various experimental results observed in Cu2O photocatalysis and can serve as an efficient strategy benefitting photocatalyst design.

Enhanced visible light photocatalytic activity of nanostructured SiO2-TiO2 thin films through optimizing thickness

Thin films of silicon dioxide-titanium dioxide (SiO2-TiO2) with different thicknesses were deposited by a simple dip-coating method in a repetition behavior followed by heating processes. Choosing the optimum thickness is accounted as an approach for improving photocatalytic and hydrophilicity properties of a thin film. The obtained results from FESEM and AFM characterizations showed that with increasing thickness, the surface roughness increases from 3.089 nm to 132.8 nm. The XRD patterns indicate the presence of anatase phase for the SiO2-TiO2 thin film. Optical measurements were used to calculate thickness, generation rate of photocarriers, band gap, and refractive index of the samples. Decrease of band gap with increasing thickness makes the layer more proper for photocatalytic activity under visible light. It is obtained that the generation rate of carriers has the highest value (17.16 × 1024 m−3s−1) for the thickness of 336 nm. PL spectra for the thickness of 336 nm confirmed the presence of defects which reduce the recombination rate and improve charge carrier separation. XPS was used to distinguish the chemical composition. Variation of defect concentrations, number of grain boundaries, and surface roughness with thickness were considered as the main parameters affecting the photocatalytic performance. The highest photodegradation was obtained for 336 nm thick film under illumination of visible light (100% degradation of 40 ml solution of 10 mg l−1 methylene blue (MB)). This research provides a systematic study on the structural and optical properties of the different thick SiO2-TiO2 films with goal of enhancing photocatalytic activity in the visible light region.

Effect of indium (III) doping on Ag3PO4 catalyst stabilization and its visible light photocatalytic activity toward toxic dyes in water.

Indium(III)-doped Ag3PO4 (In-AgP) catalysts at different weight percentages were elaborated by co-precipitation and subjected to XRD, SEM, UV-vis DRS, and FTIR characterization. The prepared catalysts were of spherical morphology and their diameters depends on doping dosage. The whole materials crystallize in a centered cubic system with a slight dissimilation in the positions of the characteristic peaks as a function of indium dosage. The photocatalytic performance of the catalysts under visible light was investigated in the photocatalytic degradation of anionic dye (methyl orange (MO)) and cationic dye (auramine O (AO)) in moderate acid, neutral, and basic pH conditions. Results showed more selectivity to MO than AO. Furthermore, indium-doped samples are more active in the acidic medium than the pure Ag3PO4 (AgP), and 10%In-AgP catalyst presents the highest activity. The degradation efficiency reached 99 % in 60 min for MO and in 180 min for AO. In addition, a high recycling stability was achieved and the catalyst retains its degradation capacity above 99 % after five cycles.

A novel CoMoO4 enwrapped ZIF-8 nanocomposite with enhanced visible light photocatalytic activity

A hybrid nano catalyst, CoMoO4 anchored zeolitic imidazolate framework-8 (ZIF-8) has been synthesized by simplest in-situ chemical method. The characterization results showed that the CoMoO4@ZIF-8 composites had a crystalline structure with a uniform distribution of the Cobalt molybdate particles on the ZIF-8 surface. The FTIR spectra revealed the presence of characteristic peaks for both ZIF-8 and CoMoO4, indicating the successful incorporation of the metal molybdate into the ZIF-8 framework. The SEM-EDS analysis showed that the CoMoO4 nanoparticles (NPs) have been evenly distributed on the ZIF-8 surface. In HRTEM, some rod-like CoMoO4 is observed on the surface of the ZIF-8 material, which is stacked in a disorderly manner and a porous channel structure is formed. The photocatalytic activity of the CoMoO4@ZIF-8 has been evaluated using the degradation of methylene blue (MB) and antibiotic Ciprofloxacin (CIP) under visible light. The optimal photocatalytic activity was achieved with the CoMoO4@ZIF-8 composite, which showed a degradation efficiency of 100% under visible light after 40 min of irradiation. In conclusion, the CoMoO4@ZIF-8 composites showed enhanced photocatalytic activity under visible light, and it exhibited the best performance compared with pure CoMoO4 and ZIF-8.

Preparation of Y3+-doped Bi2MoO6 nanosheets for improved visible-light photocatalytic activity: Increased specific surface area, oxygen vacancy formation and efficient carrier separation

Preparation of Y3+-doped Bi2MoO6 nanosheets for improved visible-light photocatalytic activity: Increased specific surface area, oxygen vacancy formation and efficient carrier separation

Enhanced Visible Light Photocatalytic Activity of g-C3N4/SiO2@TiO2 Heterojunction Fabricated by Hydrothermal Synthesis

Photocatalysts that can utilize sunlight energy have attracted attention. In this study, g-C3N4 and mesoporous SiO2@TiO2 particles were mixed by hydrothermal synthesis. g-C3N4 was made by a simple method of directly heating melamine. Mesoporous SiO2@TiO2 was prepared using the stover method. These two types of particles were then mixed by hydrothermal synthesis. Hydrothermal synthesis reduced the size of the g-C3N4 particles, and they bound more closely with the TiO2 particles. The degradation of methylene blue dye by visible light was performed to evaluate the organic degradation of the mixed particles. In addition, the mixed particles were formed into a thin film by the spin-coating method. The film's methylene blue degradation performance and the film's power generation performance in a battery were evaluated. The film showed high convenience in the practical application of photocatalytic degradation of organic pollutants because it can be easily separated from the treated liquid after organic matter degradation.