Visible Light Absorption Ability Research Articles

Dual Regulation of Sensitizers and Cluster Catalysts in Metal-Organic Frameworks to Boost H2 Evolution.

Photocatalytic efficiency is closely correlated to visible-light absorption ability, electron transfer efficiency and catalytic center activity of photocatalysts, nevertheless, the concurrent management of these factors to improve photocatalytic efficiency remains underexplored. Herein, we proposed a sensitizer/catalyst dual regulation strategy on the polyoxometalate@Metal-Organic Framework (POM@MOF) molecular platform to construct highly efficient photocatalysts. Impressively, Ni-Sb9@UiO-Ir-C6, obtained by coupling strong sensitizing [Ir(coumarin 6)2(bpy)]+ with Ni-Sb9 POM with extremely exposed nickel site [NiO3(H2O)3], can drive H2 evolution with a turnover number of 326923, representing a record value among all the POM@MOF composite photocatalysts. This performance is over 34 times higher than that of the typical Ni4P2@UiO-Ir constructed from [Ir(ppy)2(bpy)]+ and Ni4P2 POM. systematical investigations revealed that dual regulation of sensitizing and catalytic centers endowed Ni-Sb9@UiO-Ir-C6 with strong visible-light absorption, efficient inter-component electron transfer and high catalytic activity to concurrently promote H2 evolution. This work opens up a new avenue to develop highly active POM@MOF photocatalysts by dual regulation of sensitizing/catalytic centers at the molecular level.

Synthesis of Photocatalyst Based on WO3 Applying for the Treatment of Tetracycline Antibiotics

In this paper, WO3/g-C3N4 photocatalysts were fabricated by ultrasonic-assisted hydrothermal method at different mole ratios of WO3/g-C3N4. Ultraviolet–visible absorption spectroscopy (UV-Vis DRS) and photoluminescence (PL) results indicated that WO3/g-C3N4 photocatalyst with the WO3/g-C3N4 mole ratio of 1/1 (WC-1) showed visible light absorption ability and prevented electron-hole recombination rate better than WO3, g-C3N4 and other composites. The photocatalytic activities of synthesized photocatalysts were investigated by the photocatalytic oxidation of tetracycline (TC) antibiotics under visible light. The degradation efficiency of TC in aqueous environment by the WC-1 was 79.35% after 180 minutes. This value was higher than those of other materials. The improvement in photocatalytic property of the WO3/g-C3N4 was due to the efficient generation of electrons and holes.

Visible Light Induced Photocatalytic Degradation of Diclofenac in Aqueous Solution Using Fabricated ZnO/g-C3N4 by Facile Calcination Technique.

The ability of the heterojunction between two distinct semiconductors with appropriately matched band gaps to improve the separation of photogenerated electron-hole pairs has been demonstrated to enhance photocatalytic activity. Hence, ZnO/g-C3N4 composites have been fabricated by the facile deposition and calcination of ZnO and g-C3N4. X-ray photoelectron spectroscopy, powder X-ray diffraction, and Fourier transform infrared spectroscopy confirm the formation of the composite. Scanning electron microscope, transmission electron microscope, and energy-dispersive X-ray spectroscopy morphological analysis reveal that ZnO was homogeneously spread over the g-C3N4 surface. UV-vis diffuse reflectance spectroscopy analysis shows the slightly enhanced visible light absorption ability of the composite. Photoluminescence (PL) spectroscopy and electrochemical impedance spectroscopy analysis prove the higher charge separation of the composite during the irradiation of light. The composite shows admirable photocatalytic efficiency in the visible light-driven photocatalytic degradation of an aqueous diclofenac (DFC) solution. The superoxide anion radical (•O2 -) and hydroxyl radical (•OH) act as reactive species during the degradation reaction. Probable reaction mechanisms have been proposed.

A novel 0D/3D Z-Scheme heterojunction ZnS/MIL-88(A) with significantly boosted photocatalytic activity toward tetracycline

Coupling two different photocatalytic materials to construct a heterojunction is a preferable strategy for obtaining the composite photocatalyst with high activity. Herein, a novel 0D/3D Z-scheme heterostructure ZnS/MIL-88(A) was constructed by anchoring 0D ZnS nanoparticles on the surface of the 3D MIL-88(A). The prepared ZnS/MIL-88(A) was characterized by using FT-IR, XRD, SEM, UV–vis and XPS. The photodegradation of tetracycline (TC) was conducted under the irradiation of visible light to evaluate the photocatalytic performance of ZnS/MIL-88(A). The creation of the Z-scheme heterostructure between ZnS and MIL-88(A) enables ZnS/MIL-88(A) to exhibit excellent visible-light absorption ability and dramatically boost separation and transfer of the photo-induced charge carriers. Compared with MIL-88(A), ZnS/MIL-88(A) shows prominently enhanced photocatalytic activity toward tetracycline, achieving a TC degradation rate of 94 %. The highest photodegradation rate constant (0.02083 min−1) of TC by ZnS/MIL-88(A) is 7.77 and 12.33 folds as large as those by MIL-88(A) and ZnS, respectively. After five cycles of reuse, ZnS/MIL-88(A) shows only a slightly decreased TC removal rate, presenting excellent photo-stability. Furthermore, the Z-scheme interfacial charge migration mode and the photocatalytic mechanism of ZnS/MIL-88(A) were discussed according to the band position as well as the identification result of the active species. The radicals ·O2− and ·OH generated in photocatalysis serve as major reactive species to decompose TC. This work provides a new way for designing efficient composite photocatalysts.

Wavelength-dependent photoelectrochemical sensor array based on Bi2WO6/TiO2 electrospun nanoheterojunction for multiple antioxidants identification and total antioxidant capacity analysis in natural tea

Evaluating total antioxidant capacity (TAC) have been playing a vital role in health guidelines, the analysis of nutritional composition in foods, and the diagnosis and treatment of oxidative stress-induced disease. However, numerous antioxidants with similar physicochemical properties make them very difficult to be discriminated because of the similarly analytical signal output. In this work, a novel wavelength-dependent and three-channel photoelectrochemical (PEC) sensor array based on Bi2WO6/Vo-TiO2 electrospun nanostructures was established for the identification of antioxidants in natural teas. The formation of heterojunction interfaces between Bi2WO6 nanosheet and Vo-TiO2 NFs, and the introduction of the oxygen vacancies in TiO2 NFs promoted the visible light absorption ability and electron transfer rate of Bi2WO6/Vo-TiO2 NFs, causing the differences of photocurrent response to different antioxidants under different wavelengths. Furthermore, excited wavelengths, antioxidant types, and photocurrent were regarded as three-factors of fingerprint to accurately discriminate five antioxidants via linear discriminant analysis (LDA). Finally, the PEC sensor array was able to estimate TAC in five actual tea samples (green, yellow, black, white, and dark teas). This development of LDA-assisted multiplex PEC fingerprinting sensor array showed a good promise for the identification and authentication of agricultural products, and the establishment of the database.

Self-grown non-noble metal Ni2P loaded on CdS effectively accelerates electron transfer to enhance efficient photocatalytic hydrogen evolution

The development of efficient catalysts has attracted widespread attention for the hydrogen evolution reaction of water splitting via MOF derivatives to remediate the current serious environmental and energy problems. Herein, the composite catalyst Ni-MOF/Ni2P/CdS was effectively created by calcination and hydrothermal methods using Ni-MOF and CdS as raw materials. The findings demonstrated that the composite catalyst NPS-15 with the highest photocatalytic hydrogen evolution rate (18.359 mmol/g/h) was successfully developed, which is nine times greater than the hydrogen evolution rate of pure CdS and 80 times higher than that of Ni-MOF. In addition, its catalytic stability can still be maintained at about 80 % after 25 h of experience. This can be attributed to the presence of Ni2P, which improves the visible light absorption ability of the composite and promotes more photogenerated electron production. The characterization results have demonstrated that Ni2P as an electron trapping center can significantly improve the separation efficiency and transfer ability of photogenerated carriers. Meanwhile, Ni2P contains a negatively charged P, which can attract more protons to bind electrons for the reduction reaction. This study provides a probable strategy for the development of high-performance photocatalytic MOF derivatives for applications involving sustainable energy conversion.

Facile construction of copper-doped metal organic framework as a novel visible light-responsive photocatalyst for contaminant degradation

ABSTRACT Metal–organic frameworks (MOFs) with photocatalytic activity have garnered significant attentions in environmental remediation. Herein, copper-doped zeolitic imidazolate framework-7 (Cu-doped ZIF-7) was synthesized rapidly and easily using a microwave-assisted technique. Various analytical and spectroscopic methods were employed to access the framework, morphology, light absorption, photo-electrochemical and photocatalytic performance of the synthesized materials. Compared to ZIF-7, Cu/ZIF-7 (molar ratio of Cu2+ to Zn2+ is 1:1) demonstrates superior visible light absorption ability, narrower band gap, enhanced charge separation capability, and reduced electron–hole recombination performance. Under visible light irradiation, Cu/ZIF-7 serves as a Fenton-like catalyst and demonstrates exceptional activity for contaminant degradation, while virgin ZIF-7 remains inactive. With the addition of 9.8 mmol H2O2 and exposure to visible light for 30 min, 10 mg of Cu/ZIF-7 can completely decompose RhB solution (10 mg/L, 50 mL). The synergistic effect of the Cu/ZIF-7/H2O2/visible light system is attributed to visible light photocatalysis and Fenton-like reactions. Cu/ZIF-7 demonstrates excellent catalytic performance stability, with only a slight decrease in degradation efficiency from an initial 97.0% to 95.4% over four cycles. Additionally, spin-trapping ESR measurements and active species trapping experiments revealed that h+ and ·OH occupied a significant position for Rhodamine B (RhB) degradation. Degradation intermediate products of Rhodamine B have been identified using UPLC-MS, and the degradation pathways have been proposed and discussed. This work offers a facile and efficient technique for developing MOF-based visible light photocatalysts for water purification.

Ultrasensitive monitoring of PCB77 in environmental samples using a visible-driven photoelectrochemical sensing platform coupling with exonuclease I assisted in target recycling

Due to the urgent need for detecting trace amounts of 3,3′,4,4′-tetrachlorobiphenyl (PCB77) in the environment, we have developed an efficient and visible-driven photoelectrochemical (PEC) sensing platform based on carbon quantum dots (CQDs) modified titanium dioxide nanorods (TiO2 NRs), coupling with exonuclease I (Exo I) assisted in target recycling for significant signal amplification. CQDs/TiO2 NRs with high visible-light absorption ability and electron-hole separation efficiency is used as photoactive substrate for anchoring anti-PCB77 aptamer and its complementary DNA (cDNA). With the addition of PCB77, the specific interaction between PCB77 and its aptamer forces aptamer to separate from the electrode surface, resulting in an increase in photocurrent density. Adding Exo I in the test system, a self-catalytic target cycle was motivated, which significantly increased the PEC signal by more than twice, achieving signal amplification. The relationship between the photocurrent density changes and the concentrations of PCB77 are utilized to achieve quantitative detection of PCB77. The designed PEC sensing platform has good analytical performance with a detection limit as low as 0.33 pg L−1, high selectivity and stability. Moreover, the PEC sensor is successfully used to evaluate the content of PBC77 in the environment samples. The established sensing platform provides a simple and efficient method for detecting trace amounts of PCB77 in the environment.

Effect of Laser Energy Density on Photophysical and Photocatalytic Properties of BiVO4 Single‐Crystal Thin Film

Effect of Laser Energy Density on Photophysical and Photocatalytic Properties of BiVO₄ Single‐Crystal Thin Film

“Edge in-situ heterogeneous” BiOI based on defect engineering and non-noble metal deposition: Boosting visible-light photocatalytic sterilization

The inherent narrow band gap of bismuth oxyiodide (BiOI) consistently leads to the rapid recombination of photogenerated carriers, significantly constraining its practical utility. To combat this shortcoming, we devise a Bi/BiOI1−x (BB) nanosheet with edge heterostructure. It is modified by the introduction of both iodine defects and in-situ bismuth deposition through high-temperature calcination and solvothermal strategy. Notably, the in-situ deposition of bismuth enhances the visible-light absorption ability of BiOI. And the incorporation of iodine defects initiates a modification in the band position of BiOI, ultimately diminishing the electron-hole recombination rate effectively. More importantly, facilitated by the major work function of bismuth, a Schottky barrier is formed at the BB heterojunction interface, which effectively promotes the separation of photogenerated charges within BB. And the photocurrent intensity of BB is 4 times higher than that of pure BiOI. These ingenious designs result in a significant boost in the generation of reactive oxygen species (ROS) through the accumulation of electrons and holes on the surfaces of both Bi and BiOI1−x. And BB photocatalyst shows an outstanding broad-spectrum bactericidal performance. The antibacterial rates against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) are 88.01% and 90.01%, respectively, which are increased by 80.6% and 83.8% compared with BiOI. Moreover, in vivo experiments provide compelling evidence for the BB photocatalyst’s potential in promoting wound healing. The healing rate after BB treatment has already reached more than 95% on the fifth day. This work offers valuable insights on enhancing the sterilization performance of photocatalysts based on the synergistic effects of defect engineering and non-noble metal deposition.

Experimental and theoretical studies on the photoelectrocatalytic property of titanium dioxide nanoarrays improved by S,N co-doped graphene quantum dots

In this paper, sulfur and nitrogen co-doped graphene quantum dots (S,N-GQDs) were compounded with titanium dioxide (TiO2) nanorods by chemical surface modification. S,N-GQDs in diameter of 5 nm are uniformly distributed on the surface of TiO2 nanorod arrays. The presence of CS bonds in S,N-GQDs not only broaden the absorption of visible light by GQDs, but also enhanced the visible light absorption of S,N-GQDs/TiO2 composites. The photocurrent densities of S,N-GQDs/TiO2 were 3.66 times that of unmodified TiO2. The calculation results of density functional theory (DFT) showed that the band gap of S,N-GQDs is significantly reduced compared to GQDs, indicating that electrons are more likely to transit to higher energy levels and form more activation sites. Moreover, compared with TiO2, the DFT calculation results of band gap, density of states and charge density difference of S,N-GQDs/TiO2 showed that S,N-GQDs/TiO2 had a wide wavelength of visible light absorption and better electron-hole separation ability, resulting in the superior photoelectrocatalytic property. This research provides favorable analytical value for the development of photocatalysts based on heterostructures.

Enhanced charge separation via ZnIn2S4@S-doped-C3N4 S-scheme heterojunction for efficient photocatalytic water splitting under visible light

Heterojunction photocatalysts possess high efficiency in photogenerated electron-hole separation, which give significant advantages in the field of solar hydrogen production. Herein, a novel ZnIn2S4@S doped g-C3N4 (ZIS@SCN) heterojunction with mesoporous structure was prepared for photocatalytic water splitting under visible light. Characterization showed that the element of S was successfully introduced into g-C3N4 (CN) by replacing N to form C–S–C bonds and significantly enhanced the visible light absorption ability. The constructed heterojunction exhibited excellent photocatalytic hydrogen evolution under visible light. The best performance belonged to the sample of ZIS@100SCN. The corresponding H2 production rate reached 9.3 mmol h−1 g−1, which was 1.87-fold higher than that of the undoped one. More importantly, the heterojunction realized overall water splitting of H2 and O2 evolution simultaneously with good stability. The mechanism analysis indicted that introducing the element of S could regulate the band structure of CN and induce the charge transfer switching of a ZnIn2S4@g-C3N4 (ZIS@CN) photocatalyst from Ⅰ-type to S-scheme, which promoted the efficient spatial charge separation and maintained the high redox ability of the ZIS and SCN. This work provides an insight in construction high performance S-scheme heterojunction for water splitting with a doping method.

Enhanced photocatalytic H2 evolution over conjugated polymer/Au@TiO2 ternary heterojunction under visible light: Enriched photons input from polymers

Exploring efficient and stable TiO2-based photocatalysts for visible-light H2 evolution remains a great challenge. Here, a novel ternary heterojunction (THSO/Au@TiO2) was successfully synthesized by a facile in-situ polymerization strategy, which showed highly enhanced photocatalytic activity towards H2 evolution under visible light. The optimized THSO/Au@TiO2-26 exhibited an excellent photocatalytic performance to H2 evolution (7504 μmol/g/h), which was 16.31, 416.89 and 1.81 times higher than that of THSO, TiO2 and THSO/TiO2 photocatalysts, respectively. This excellent performance should be attributed to the excellent visible light absorption ability of the polymer THSO, and the local surface plasmonic resonance effect of Au nanoparticles (Au NPs), promoting separation and transfer of photo-generated charge carriers. This work presents new insights for the design of efficient and rational TiO2-based photocatalytic systems to enhance photocatalytic performance towards H2 evolution under visible light.

Synthesis of NiFe2O4 Photocatalyst to Apply for Treatment of Residual Tetracycline in Aqueous Environment with Addition of H2O2

In the study, NiFe2O4 was successfully synthesized by hydrothermal method for treatment of residual tetracycline (TC) in aqueous environment. The study also investigated effects of H2O2 as electron an acceptor to enhance TC photocatalytic degradation of the synthesized NiFe2O4. The properties of synthesized materials were determined by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-Vis absoprtion spectroscopy (UV-VIS) and vibrating sample magnetometer (VSM) systems. The obtained results indicated that the synthesized NiFe2O4 were nano-particles with average size of approximately 50 nm. The synthesized NiFe2O4 also exhibited high visible light absorption and magnetic ability. The TC removal results indicated that the NiFe2O4 adsorbed certain amount of tetracycline under dark condition. Under visible light, the NiFe2O4 further degraded significant tetracycline amount. Finally, the study investigated that H2O2 effectively acted as electron acceptor for hydroxyl radical production to degrade tetracycline.

Construction of an all-organic S-scheme heterostructure based on PEDOT immobilized g-C3N4 nanosheets by electrostatic self-assembly with enhanced visible-light photocatalytic hydrogen production

Inspired by photosynthesis in nature, exploring all-organic S-scheme heterojunction photocatalysts for efficient H2 production is of great significance in addressing energy shortage issues. In this paper, poly(3,4-ethylenedioxythiophene) (PEDOT) immobilized g-C3N4(CN) nanosheets were constructed by an electrostatic self-assembly strategy to obtain an all-organic S-scheme heterojunction, significantly enhancing the visible-light photocatalytic H2 production performance of g-C3N4. The optimized 5PEDOT/CN exhibits the highest H2 production rate of 3.15 mmol g−1h−1, a 31.5-fold enhancement over pristine CN. According to the staggered energy band positions of two components and the results of electron spin resonance tests, the S-scheme heterojunction electron-transfer mechanism is confirmed, which greatly facilitates the spatial charge separation and retains the strong reducing ability of high-energy potential electrons for efficient photocatalytic H2 production. Based on the results of FT-IR spectra, XPS spectra, fluorescence spectra, hydroxyl radical tests and time-resolved photoluminescence spectra, it is confirmed that the significantly improved photocatalytic activity is mainly attributed to the enhanced charge separation by the S-scheme heterojunction and the tightly contacted interface dependent on N···S interactions in PEDOT immobilized CN nanosheet heterojunctions, along with the enhanced visible-light absorption ability. This work presents a novel approach to the design and fabrication of all-organic S-scheme heterojunction photocatalysts for solar-light-driven energy production.

Construction of Ag/CdZnS QDs nanocomposite for enhanced visible light photoinactivation of Staphylococcus aureus

With increasing use of antibiotics, the development of antibiotic-resistant pathogens poses a serious threat to human health and the environment. Photocatalytic inactivation of these harmful pathogens is one of the novel and non-antibiotic treatments. The study fabricated Ag NPs decorated CdZnS QDs via a facile and biological co-precipitation method using L. camara plant extract as a green alternative to treat the toxic chemicals. The fabricated Ag/CdZnS QDs (NCs) were prepared for the efficient treatment of antibiotic-resistant pathogens as they raise a major global concern. The fabricated NCs were characterized with various characterization techniques to verify its physicochemical properties. The fabricated NCs have shown excellent photo-sterilization performance of 97 % against S. aureus. The excellent activity was attributed to the decoration of Ag NPs on CdZnS QDs as it helped in shortening band gap, improved visible light absorption ability, increased active sites, and boosted photogenerated electron/hole pairs stability. Radical trapping experiment and ESR analysis indicated the involvement of •OH and h+ in the photoinactivation of bacteria. The photo sterilization reaction of NCs was carried out under different environmental conditions, including light and dark conditions and different pH conditions. The experiment was carried out in sewage-treated water in order to test the real-time application, and the fabricated NCs achieved excellent 95.9 % photo-inactivation of S. aureus cells in sewage treated water and the Chemical Oxygen Demand (COD) of the system was increased after photo inactivation treatment. The fabricated NCs have also shown excellent reusable efficiency of 95% after six runs and the photostability and anti-corrosive nature of NCs were confirmed. The study provides an insight for the employment of photocatalysis for the sterilization of pathogens in real time aquatic environment across the globe.

Rational design of covalent organic frameworks/NaTaO3 S-scheme heterostructure for enhanced photocatalytic hydrogen evolution

As a typical perovskite material, NaTaO3 has been regarded as a potential catalyst for photocatalytic hydrogen evolution (PHE) process, due to its excellent photoelectric property and superior chemical stability. However, the photocatalytic activity of pure NaTaO3 was largely restricted by its poor visible-light absorption ability and rapid recombination of photogenerated charge carriers. Therefore, a covalently bonded TpBpy covalent organic framework (COF)/NaTaO3 (TpBpy/NaTaO3) heterostructure was designed and synthesized by the post modification strategy with (3-aminopropyl) triethoxysilane (APTES) and the in situ solvothermal process. Benefiting from the enhanced built-in electric field by the interfacial covalent bonds and the formation of S-scheme heterostructure between TpBpy and NaTaO3, which were proved by the Ar+-cluster depth profile and X-ray photoelectron spectroscopy (XPS), as well as density functional theory (DFT) calculation results, both the charge transfer efficiency and the PHE performance of the TpBpy/NaTaO3 composites were significantly improved. Additionally, the composites exhibited an excellent absorption performance in the visible region, which was also beneficial for the photocatalytic process. As expected, the optimal TpBpy/20%NaTaO3 composite achieved a remarkable hydrogen evolution rate of 17.3 mmol·g−1·h−1 (10 mg of catalyst) under simulated sunlight irradiation, which was about 173 and 2.4 times higher than that of pure NaTaO3 and TpBpy, respectively. This work provided a novel strategy for constructing highly effective and stable semiconductor/COFs heterostructures with strong interfacial interaction for photocatalytic hydrogen evolution.

Synthesis of Au‐decorated WO3 nanoplates for simultaneous oxidation of RhB and reduction of Cr(VI) under visible light irradiation

AbstractTungsten oxide (WO3) nanoplates were synthesized by a simple chemical precipitation technique. These nanoplates were decorated by Au nanoparticles via photoreduction route. The obtained samples were characterized by field emission scanning electron microscopy, X‐ray diffractometry and UV–vis diffuse reflectance spectroscopy to investigate their morphological, structural and optical properties. The SEM images show the plate morphology with the size in the range of 50–150 nm, their thickness ≈10 nm; spherical‐like Au nanoparticles ≈20 nm were attached to the surface of the WO3 plates. These materials were applied for the simultaneous photocatalytic degradation of Rhodamine B (RhB) and Cr(VI) under visible light. Due to the efficient separation of photoinduced charge carriers and the enhanced visible light absorption ability, the photocatalytic performance of Au‐decorated WO3 nanoplates was higher. The main active species responsible for the photodegradation reactions were identified by different scavengers and a photocatalytic mechanism was proposed. This work represents that WO3 nanoplates are a promising candidate for the degradation of organic and inorganic pollutants from the industrial wastewater under sun light exposure.

Remediation of phenanthrene-contaminated soil by iron oxide/carboxylate-rich porous carbon composites from vinegar residue

Conversion of solid wastes into useful remediation materials is an encouraging strategy in resource recovery. Iron oxide/carboxylate-rich porous carbon composites (IOCRPC) can be synthesized by using vinegar residue (VR) and ferrous sulfate heptahydrate (FeSO4∙7 H2O) recovered from a waste acid of a titanium dioxide factory. Characterization of FeSO4-impregnated VR exhibited a high proportion of ferricarboxylate complexes [i.e. FeII(R-COO)n2-n]. Pyrolysis temperature was the most important reaction parameter to define IOCRPC phase composition. Thermal decomposition of FeII(R-COO)n2-n produced Fe3O4 nanoparticles partly at a relatively lower pyrolysis temperature (350 ºC), while successful carbonization of VR formed the porous structures of carbon. Both Fe3O4 and ferricarboxylate complexes were the components of IOCRPC responsible for its excellent visible light absorption ability. Under visible light, phenanthrene in contaminated soil was efficiently degraded (90.1%) by IOCRPC at circumneutral pH. Phytotoxicity bioassays demonstrated significant removal of toxicity after treatment with IOCRPC, highlighting its application potential in revegetation strategies.

Au/Ti3C2/g-C3N4 Ternary Composites Boost H2 Evolution Efficiently with Remarkable Long-Term Stability by Synergistic Strategies.

The use of novel two-dimensional MXene materials and conventional g-C3N4 photocatalysts to fabricate the composites for hydrogen evolution reaction (HER) has attracted much attention, for which there is plenty of room for the enhancement of hydrogen evolution rates particularly under visible light and photostability. Herein, g-C3N4 was modified by copolymerization of malonamide and melamine and used to fabricate the ternary composites of Au particles and Ti3C2 MXene, and based on the synergistic effect, the composites enhanced the hydrogen evolution rates by 2.1, 99.8, and ∞ times compared with the unmodified g-C3N4 under UV, simulated sunlight, and visible light illumination, respectively. Moreover, the composite exhibited a sustained hydrogen evolution capacity in the cycle test for up to 120 h. Theoretical calculations and experimental results indicated that the hot electrons of Au are injected into the modified g-C3N4 and transferred to Ti3C2 simultaneously along with the photogenerated electrons of the modified g-C3N4 and then further transferred to Au, forming a photogenerated electron transfer channel of Au and modified g-C3N4 → Ti3C2 → Au within the composite. Ti3C2 acts as a bridge for fast separation of photogenerated electrons and holes on Au and modified g-C3N4, playing a key role in the enhanced photocatalytic performance. In addition, the visible light absorption ability of Au also positively contributed to the enhancement of visible light photocatalytic performance by providing hot electrons. Therefore, the selection of suitable cocatalysts for the design of composites is a crucial research direction to improve the photocatalytic performance and photostability of photocatalysts.