CdS Concentration Research Articles

Electromagnetic Interference Shielding Effectiveness of Room Temperature Fabricated Manganese Dioxide/Carbon Dots Nanocomposites.

The present work is focused on the fabrication of manganese dioxide/carbon dots (MnO₂/CDs) nanocomposites at room temperature in situ co-participation method in an aqueous medium and characterized. Our study showed that the concentration of CDs controls the morphology of MnO₂/CDs nanocomposite and also acted as a reducing agent to convert potassium permanganate (KMnO₄) to MnO₂. Subsequently, nanoflowers, quasi-spherical particles, broken, and interconnected chain type of morphology was observed by adding dispersion of 0.5, 1.0, 1.5, and 2.0 ml CDs in acetone to 1 mmol KMnO₄ aqueous solution in the corresponding MnO₂/CDs-0.5, MnO₂/CDs-1.0, MnO₂/CDs-1.5, and MnO₂/CDs-2.0 composites, respectively. A plausible mechanism on the transformation of morphology of MnO₂/CDs with CDs concentration is also provided. Further, the present work also focused for the first time on the application in the electromagnetic interference (EMI) shielding of MnO₂/CD nanocomposites due to the high dielectric and conductivity. Interestingly, MnO₂/CDs-2.0 (nanochains) exhibited the highest total EMI shielding efficiency (SET) of ~39.4 dB following reflection as dominant shielding mechanism due to the high aspect ratio, highest conductivity, high dielectric loss, and impendence mismatch.

Transfer, transportation, and accumulation of cerium-doped carbon quantum dots: Promoting growth and development in wheat

New cerium-doped carbon quantum dots (CDs:Ce) were developed in this study using hydrothermal synthesis method. The small and uniform sizes and nearly spherical lattice of CDs:Ce indicate its high stability, satisfactory water solubility, and biocompatibility. Wheat was treated with Ce, CDs, and different concentrations (0.01, 0.025, 0.05, 0.1, 0.2, and 0.4 mg/mL) of CDs:Ce. The results showed that, compared with the control group, Ce, CDs, and CDs:Ce could promote the growth and development of wheat in a certain concentration range. Wheat demonstrated the optimal morphological index (compared with the control, the root number, root length, leaf length, and plant height were increased by 45%, 57%, 28%, and 46%, respectively), maximum chlorophyll content (increased by 51%) and peroxidase activity (increased by 76%), and minimum malondialdehyde content (reduced by 68%) after treatment of 0.025 mg/mL of CDs:Ce. Hence, wheat plants can adsorb and transport CDs:Ce from roots to stems and leaves through fibrovascular tissues. The majority of CDs:Ce are concentrated in roots while some accumulate in leaves. A considerable amount of CDs:Ce gather in cell walls, fibrovascular tissues, leaf veins, and stomata. CDs:Ce can be applied to agricultural production activities as a new agricultural nanofertilizer and technology of plant in vivo imaging.

To study the photoluminescence properties of CdS/PVK Nanocomposites

In optoelectronic applications Cadmium Sulfide have very good substance. Which creates interest to describe its optical studies in nanoscale range? Presently photoluminescence of CdS/PVK nanocomposites have been reported. Chemical method is used to prepare the composites and characterized them XRD, UV-Visible absorption and study their photoluminescence. The study of XRD indicates CdS nanocrystals formation having cubic zinc blend crystal structure, with three peaks of planes are respectively 111, 220, and 311. Size of particle is calculated using DebyScherrer’s technique. It has obtained within 3 to 12 nm. Results from XRD shows that when CdS concentration is increases in PVK the particle size also increases. The optical absorption spectra of the nanocomposites show blue shifted absorption edge which show increased band gap because of quantum confinement effect. Absorption side is shifted on larger wave length shows reducing the band gap with increasing CdS concentration, which indicates increase in particle size. The wavelength of 400 nm is incident on PVK, photoluminescence (PL) exhibit single peak on 451 nanometer and covers spectral range from 400 to 600 nm. The CdS nanocrystals give single peak at 530 nm when excited separately by 400 nm. In CdS/PVK nanocomposites two PL peaks are obtained, first peak due to PVK near 450 nm and second peak due to CdS near 530 nm.PL intensity decreases with increasing concentration of CdS in PVK.

Ultrasonication-assisted host–guest inclusion complexes of β-cyclodextrins and 5-hydroxytryptophan: Enhancement of water solubility, thermal stability, and in vitro anticancer activity

The use of ultrasonic waves for the preparation of inclusion complexes in pharmaceutical industries has increased, owing to their versatility, promising nondestructive capability, and short reaction time. 5-Hydroxytryptophan (5-HTP), a precursor of serotonin, is used therapeutically, in the clinical setting, for psychiatric disorders such as anxiety and depression. In this study, 5-HTP is used as a guest molecule to prepare β-cyclodextrins (CDs; β-CD, HPβ-CD, and SBEβ-CD) inclusion complexes with the assistance of the ultrasonic method. The solubility of 5-HTP increases linearly as the concentration of CDs increased, confirming the 1:1 stoichiometry of the complex, obtained using UV–visible and fluorescence spectroscopy. The structural characteristics of the solid inclusion complexes are analyzed using various spectroscopic and microscopic techniques such as FTIR spectroscopy, PXRD, TGA, and FE-SEM. Molecular modeling elucidates the most stable inclusion model and phase solubility studies indicate that 5-HTP and SBEβ-CD form a 1:1 inclusion complex with an apparent stability constant of 1592.5 M−1. Furthermore, in vitro cytotoxicity studies show that the CDs:5-HTP complex has a better antitumor efficacy than pure 5-HTP. Thus, ultrasonication can be utilized as an advanced, time-saving, and cost-effective method for the generation of CDs:5-HTP inclusion complexes, resulting in the potential development of anticancer drugs.

Mechanism of action and cellular responses of HEK293 cells on challenge with zwitterionic carbon dots

Carbon, an extremely versatile element has great demand in the field of nanoscience. Carbon-based nanostructures are exponentially increased due to its wide range of applications in biotechnological and environmental approaches; hence, its safety assessment is of greater concern. In the present study, high quantum yielding zwitterionic carbon dots were synthesized, characterized and its safety assessment at different concentration ranges (50–1600 μgmL−1) on HEK 293 cells was carried out. Cellular, mitochondrial, lysosomal integrity and ROS generation were assessed using specific fluorochromes.The key cellular event apoptosis was assessed by annexinpropidium iodide staining using imaging flow cytometry. Moreover, the mRNA levels of the apoptotic genes were determined by real-time PCR. The results revealed that the cell viability assays (MTT, NR) and mitochondrial membrane potential were altered on exposure to a higher concentration of zwitterionic CDs for 24 h. Also, annexinpropidiumiodidestaining exhibited an increased percentage of apoptotic cells upon exposure to zwitterionic CDs at higher concentrations. Further, apoptosis was confirmed by significantlyincreased expression of pro-apoptotic gene (Bax) together with decreased expression of Bcl-2/Bax ratio. Collectively, this study suggests that zwitterionic CDs induce apoptosis in HEK 293 at higher concentration and the safe range for its intended application is found to be 50−200 μg/mL.

Effects of cadmium on the behavior and regeneration of Dugesia japonica

This study was undertaken to evaluate the toxic effect of cadmium sulfate (Cds) on planarians (Dugesia japonica), and the suitability of planarians as an alternative animal model for toxicity studies. Planarians were exposed to varying concentrations of experimental solutions containing 0.1–25 mg/L Cds, and incubated for 1, 3, and 5 hrs. Motility, seizure-like behaviors (c-like, head-bop, snake-like, and screw-like) and regeneration ability of the amputated fragment were subsequently evaluated. Results showed decreased motility with increasing concentrations of Cds (p<0.05), with the lowest motility being observed at the highest concentration of 25 mg/L Cds. Results also indicate that seizure-like behavior patterns were significantly affected by increments in the Cds concentrations, especially the c-like and head-bop behaviors were notably increased. Compared to the control, the regeneration ability of the planarians was decreased in the experimental solutions containing Cds. Planarians exposed to Cds showed either delayed eye formation or no eye regeneration during incubation. Moreover, increased concentrations of Cds resulted in failure to regenerate and death of the planarians. In conclusion, this study confirm that the heavy metal Cds exerts a toxic effect on planarians. Furthermore, the performances of the planarians in the experimental period exhibit their suitability as an alternative animal model for toxicity studies.

Effects of cadmium on the behavior and regeneration of Dugesia japonica

This study was undertaken to evaluate the toxic effect of cadmium sulfate (Cds) on planarians (Dugesia japonica), and the suitability of planarians as an alternative animal model for toxicity studies. Planarians were exposed to varying concentrations of experimental solutions containing 0.1–25 mg/L Cds, and incubated for 1, 3, and 5 hrs. Motility, seizure-like behaviors (c-like, head-bop, snake-like, and screw-like) and regeneration ability of the amputated fragment were subsequently evaluated. Results showed decreased motility with increasing concentrations of Cds (p<0.05), with the lowest motility being observed at the highest concentration of 25 mg/L Cds. Results also indicate that seizure-like behavior patterns were significantly affected by increments in the Cds concentrations, especially the c-like and head-bop behaviors were notably increased. Compared to the control, the regeneration ability of the planarians was decreased in the experimental solutions containing Cds. Planarians exposed to Cds showed either delayed eye formation or no eye regeneration during incubation. Moreover, increased concentrations of Cds resulted in failure to regenerate and death of the planarians. In conclusion, this study confirm that the heavy metal Cds exerts a toxic effect on planarians. Furthermore, the performances of the planarians in the experimental period exhibit their suitability as an alternative animal model for toxicity studies.

Antibacterial carbon dots derived from polyethylene glycol/polyethyleneimine with potent anti‐friction performance as water‐based lubrication additives

AbstractCarbon dots (CDs) are obtained from polyethylene glycol and polyethyleneimine by a simple hydrothermal method at 200°C. The water dispersion of CDs (0.2 wt%) remains transparent even after standing for a month. Next, the tribological properties of CDs as water lubricating additives are evaluated by multifunctional micro‐friction tester. Specifically, after adding 0.2 wt% of CDs, the mean friction coefficient and wear volume of water‐based lubrication are reduced by 59.77 and 57.97%, respectively. Meanwhile, the antibacterial properties of CDs are evaluated by minimum inhibitory concentrations test, long‐lasting antibacterial stability, and biological scanning electron microscopy experiment. The minimum inhibitory concentrations of CDs against Escherichia coli and Staphylococcus aureus are 62.5 and 15.56 μg ml−1, respectively. And the result show that, after co‐cultivation with CDs, the integrity of the bacteria is seriously destroyed, which accelerates the leakage of the cell contents and eventually leads to the death of bacteria. More importantly, the antibacterial performance can be maintained stably at least for 1 month even if the continuously adding of bacterial suspensions. Therefore, as an advanced lubricating additive with antibacterial and anti‐friction functions, the prepared CDs have a bright future in the field of water lubrication.

Carbon dots decorated NiCo hydroxycarbonate hierarchical nanoarrays on carbon cloth with high areal capacitance as pseudocapacitor electrode

The electrode materials with low specific capacitance seriously restricts the development of supercapacitors. Herein, CDs modified NiCo hydroxycarbonate (NiCoHC/CDs) hierarchical nanoarrays were grown on carbon cloth (CC) through a simple step by step hydrothermal method. The morphology, crystalline structure and electrochemical performance of the as-prepared NiCoHC nanoarrays on CC can be readily manipulated by varying the concentration of CDs in reaction solution. The optimized NiCoHC/CDs-2 nanoarrays on CC showed a high areal specific capacitance of 14.83 F cm‐2 (1964.64 F g‐1) at a current density of 5 mA cm‐2, excellent rate performance with a high capacitance retention of 46.8% at 50 mA cm‐2 and a good cycle stability with capacitance retention of 76.1% after 3000 cycles at 20 mA cm‐2. Furthermore, an asymmetric aqueous supercapacitor, which assembled using NiCoHC/CDs-2 as cathode and oxidized carbon cloth as anode in 6 M KOH, delivered a specific capacitance of 2.23 F cm‐2 (18.58 F cm‐3) in a potential window of 0‐1.5 V. An energy density of 5.82 mWh cm‐3 can be obtained at the power density of 33.58 mW cm‐3 and maintained 1.90 mWh cm‐3 at 98.99 mW cm‐3. Moreover, after 2000 cycles at 20 mA cm‐2, the device still retained 69.8% capacitance retention.

Highlighting the importance of optimal defect density through band structure and photocatalytic studies

Interface energetics plays a substantial role in the efficient charge transfer between semiconductor materials. The concentration of donors or acceptors at the junction determines the direction of charge flow. In this work, CdS was doped to TiO2 progressively to explore the electronic structure modification and its associated effect on charge dynamics. Results suggest that loss of dipole moment with increasing CdS concentration; causing the work function (WF) values of the composites to increase. The dipole-dipole repulsion occurs as a consequence of a decrease in Cd-Cd distance at higher doping concentrations. When present in optimal concentration, the surface dipoles besides aiding in efficient charge transfer, accelerate the chemisorption process at corrugated surfaces. Apart from the optoelectronics, efforts have been made to understand the hindering role of higher defect concentration in triggering the thermodynamically favored undesired photocatalytic reactions, which drastically reduce the quantum yield of the process. This work may provide some insights to tune the work function (WF) values in applications that involve optoelectronic and photocatalytic studies.

Comparative analysis of solubilization and complexation characteristics for new antifungal compound with cyclodextrins. Impact of cyclodextrins on distribution process

From a pharmaceutical standpoint, cyclodextrin-based products have deservedly gained substantial market share due to their ability to improve undesirable physicochemical properties of drugs. In this study the solubility of a potenial antifungal compound (L-173) has been improved essentially by addition of β-cyclodextrin (β-CD), 2-hydroxypropyl-β-cyclodextrin (HP-β-CD), and heptakis(2,6-di-O-methyl)-β-cyclodextrin (DM-β-CD) in aqueous solutions (pH 2.0 and pH 7.4) at 298.15–313.15 K. The phase solubility diagrams were constructed. The stoichiometric ratio of the complexes was determined as 1:1. The stability constants of L-173 with all three CDs in acidic medium belong to the range optimal for the improvement of the bioavailability of hydrophobic drugs. DM-β-CD was assigned as the best solubilizer for L-173. The driving forces of the solubilization and complexation process were revealed by evaluating the thermodynamic parameters. The distribution behavior of L-173 in the 1-octanol/buffer and 1-hexane buffer systems at pH 2.0 and pH 7.4 in the presence of different CDs concentrations was studied. The reduction of the distribution coefficients with the increasing of CD concentration was detected due to complex formation. Based on the analysis of the solubility-distribution relationship, the L-173 partitioning between the biological tissues and penetration through the biological membranes in case when cyclodextrins are used as solubilizers was evaluated, and the optimal CD concentrations were proposed.

Mn-doped CdS quantum dots as sensitizers in solar cells

CdS and different concentrations of Mn+2 doped CdS quantum dots are synthesized via simple chemical method on poly-vinyl alcohol matrix. The doped and undoped CdS quantum dots are characterized by using UV–Vis absorption spectroscopy, X-ray diffraction, and energy dispersive X-ray spectroscopy to revel the changes in optical and structural properties due to Mn doping. The synthesized quantum dots were used as sensitizing layer on a ZnO thin film solar cell and tested under artificial illumination condition to obtain the current density-voltage characteristics. A significantly higher efficiency of about 2.09% was obtained for Mn doped CdS quantum dots compared to that of 1% efficiency in pure CdS quantum dot sensitized solar cell.

Effect of photodeposition conditions on Ni–CdS photocatalysts and its role in the photoactivity for H2 production from ethanolic solutions

The incorporation of Ni-based cocatalysts on CdS by photodeposition has been investigated as a way of improving the photocatalytic efficiency of CdS for the production of hydrogen from ethanolic solutions under solar light. Specifically, this work investigates the effect of the concentration of CdS in the suspensions used in the photodeposition of Ni over the structure, chemical state, and dispersion of the Ni species deposited on CdS. The change in the concentration of CdS during photodeposition leads to changes in the light absorption capacity of CdS by insertion of Ni2+ ions in its structure, and also in the concentration of heterojunctions formed by the close interaction between the Ni species (Ni(OH)2) and CdS. The Ni–CdS photocatalyst prepared with the lower CdS concentration in the suspension during the photodeposition of Ni showed the highest photoactivity for the production of hydrogen from ethanolic solutions. This outcome is related to the combination of an improvement in the light absorption ability, i.e. narrow band gap associated with a higher insertion of Ni2+ ions in the structure, and an increase in the heterojunctions of Ni(OH)2 on CdS which improves the photo carrier generation, separation and availability on the photocatalyst surface, thus resulting in a more efficient photoproduction of hydrogen.

Photoluminescence emission from nanostructured porous preparations of CdS-ZnTiO3 assembled nanoparticles.

This study reports the structural and optical properties of CdS/ZnTiO3 nanocomposites prepared using a chemical bath and different titanate concentrations. Commercial ZnTiO3 nanoparticles were introduced into a chemical bath that had been used to produce CdS semiconductor nanoparticles (NPs). Here, the growing CdS crystallites precipitated onto the suspended zinc titanate NPs. X-ray diffraction patterns revealed that samples of CdS/ZnTiO3 nanopowders were made of cubic ZnTiO3 and hexagonal CdS wurtzite. The morphology of the particles was studied using transmission electron microscopy and scanning electron microscopy images. These images demonstrated the different characteristics of the CdS/ZnTiO3 nanocomposites and their dependence on titanate concentration when placed into the CdS-growing solution. Photoluminescence spectra showed three main emission bands for the electron transitions in the CdS/ZnTiO3 composite. This composite produced three photoluminescence bands, the intensities of which depended on composite shape, which in turn depended on the relative concentrations of CdS and ZnTiO3 .

Cytotoxicity, Antioxidant, Antibacterial, and Photocatalytic Activities of ZnO-CdS Powders.

In this work, ZnO–CdS composite powders synthesized by a simple chemical precipitation method were thoroughly characterized. The morphological, structural, compositional, photocatalytical, and biological properties of the prepared composites were investigated in comparison with those of the pristine components and correlated with the CdS concentration. ZnO–CdS composites contain flower-like structures, their size being tuned by the CdS amount added during the chemical synthesis. The photocatalytic activity of the composites was analyzed under UV irradiation using powders impregnated with methylene blue; the tests confirming that the presence of CdS along the ZnO in composites can improve the dye discoloration. The biological properties such as antioxidant capacity, antibacterial activity, and cytotoxicity of the ZnO, CdS, and ZnO–CdS composites were evaluated. Thus, the obtained composites presented medium antioxidant effect, biocidal activity against Escherichia coli, and no toxicity (at concentrations less than 0.05 mg/mL for composites with a low CdS amount) for human fibroblast cells. Based on these results, such composites can be used as photocatalytic and/or biocidal additives for photoactive coatings, paints, or epoxy floors, which in their turn can provide a cleaner and healthier environment.

Camphor Sulfonic acid Protonated Poly (2, 5-dimethoxyaniline) - Cadmium sulfide blend thin film for Ammonia gas Sensing Application

Poly (2, 5-dimethoxyaniline) and Cadmium sulfide nanocomposite blend have been prepared by low cost, feasible oxidative polymerization method. Poly (2, 5-dimethoxyaniline) has been protonated with Camphor sulfonic acid. nanocomposite blend thin films were obtained by blending with CdS into Poly (2, 5-dimethoxyaniline) for different weight percentage by dip coating. The structural, morphological, optical characterizations of pristine Poly (2, 5-dimethoxyaniline) and nanocomposite blend thin films were analyzed. The XRD pattern shows that the crystallinity of the blend film increases with increasing CdS concentration. FESEM images shows porous blend film. The UV-Vis and Photoluminence spectra analysis shows the extension of conjugation length with decreasing band gap with increasing CdS concentration. The presence of functional groups were studied from FTIR spectra. The CSA protonated Poly (2, 5-dimethoxyaniline) – Cadmium sulfide blend films have been investigated as ammonia gas.

Efficient Charge Transfer in Heterostructures of CdS/NaTaO3 with Improved Visible-Light-Driven Photocatalytic Activity.

Photocatalyst NaTaO3 with a cube-shaped morphology and an average particle size of 100 nm was synthesized using an effortless hydrothermal method. The composite heterostructures of CdS/NaTaO3 with variable concentrations of CdS were fabricated after the surface functionalization of bare NaTaO3 using 3-mercaptopropionic acid. As-synthesized photocatalysts were characterized using powder X-ray diffraction analysis, Raman spectroscopy, field-emission scanning and transmission electron microscopies with energy-dispersive X-ray spectroscopy furnished with elemental mapping, multipoint Brunauer–Emmett–Teller (BET), and UV–vis diffuse reflectance spectroscopy. Average lifetime (τavg) of photoexcitons in heterostructures was studied using photoluminescence (PL) empowered with the time-correlated single-photon counting technique. The diminishing PL peak intensity and reduced average lifetime (τavg) of photoexcitons in heterostructures indicate the inhibition of photoexciton recombination along with efficient photoexciton exchange between heterostructures. As-synthesized heterostructures demonstrate enhanced visible-light harvesting and appreciably increased the photocatalytic performance toward the degradation of dye rhodamine B. This work highlights the importance of heterostructures with new archetypes which may provide a lead to develop highly capable and reusable photocatalysts to organic dye degradation.

Stability of microencapsulated strawberry flavour by spray drying, freeze drying and fluid bed

The protection and stability of flavours is the great importance in the food industry in order to produce high-quality products. For this reason, the main goal of this paper was.to study the stability of a microencapsulated strawberry flavour using different encapsulating agents and drying techniques: spray drying, freeze drying and fluid bed. According to the quantification of volatile compounds, the blend MDs/Hi-Cap (9/1) at a fixed concentration of CDs (1.7%) was the most appropriate for microencapsulating the strawberry flavour. The best drying yield was observed in the case of freeze drying. In the case of the moisture content, spray drying samples presented the lowest values, followed by freeze drying and fluid bed. The study of stability at different temperatures and times revealed that the presence of CDs in the blend enabled a higher presence of volatile compounds in the powder than in its absence. Microphotographs showed smooth spherical particles in the case of spray drying, whereas the structure of the powder was amorphous, like glass, with freeze drying and irregular in the case of fluid bed.

Carbon dots modified WO2-NaxWO3 composite as UV-Vis-NIR broad spectrum-driven photocatalyst for overall water splitting

Abstract The utilization of solar energy and valid photocatalyst is one of the most effective strategies to achieve water splitting into hydrogen (H2) and oxygen (O2). Although enormous effort has been devoted to photocatalysts, the sunlight still cannot be fully utilized by the developed photocatalysts. It is important but remains challenging to develop a broad spectrum-driven photocatalyst for overall water splitting. Here, we design a UV-Vis-NIR broad spectrum-driven carbon dots modified WO2-NaxWO3 (WO2-NaxWO3-CDs) composite as photocatalyst for overall water splitting without requirement of any sacrificial agents or cocatalysts. When the concentration of CDs in the sample is 0.008 gCDs/gcatalyst, the WO2-NaxWO3-CDs shows the highest photocatalytic activity with stoichiometric ratio of H2/O2 evolutions and their rates are 0.05/0.02, 2.58/1.24, 4.74/2.28 μmol/h under UV (λ 760 nm) light irradiation, respectively. It is also impressive that the photocatalyst shows excellent stability for about 6 cycles of repetitive experiments. The WO2-NaxWO3-CDs composites functioned as broad spectrum-driven photocatalyst for overall water splitting should attribute to the synergistic effect of WO2-NaxWO3 and CDs, in which the WO2-NaxWO3 provides the suitable bandgap, while the CDs can enhance light absorption and accelerate separation efficiencies of photo-generated charge carriers.

All-solid-state Z-scheme system of NiO/CDs/BiVO4 for visible light-driven efficient overall water splitting

Solar light driven photocatalytic water splitting to produce hydrogen (H2) and oxygen (O2) on large scale is a promising solution to acquire the clean and sustainable energy sources. Enlightened by mimicking natural Z-scheme photosynthesis, the artificial visible light-driven water splitting photocatalyst of NiO/carbon dots/BiVO4 (NiO/CDs/BiVO4) composite was constructed. The designed NiO/CDs/BiVO4 as all-solid-state Z-scheme photocatalyst exhibits efficient photocatalyatic activity for overall water splitting without any cocatalysts or scavengers. In the Z-scheme system, the NiO and BiVO4 can respectively act as H2 evolution and O2 evolution photocatalysts, while the CDs can serve as solid electron mediator. The optimal NiO/CDs/BiVO4 photocatalyst shows the H2 and O2 production rates of 1.21 and 0.60 μmol·h−1, respectively, with the CDs concentration in the composite of 5 wt% and the mass ratio of NiO to BiVO4 of 3. The incorporation of CDs employed as the solid-state electron mediator boosts the effective electron transfer and charges separation, resulting in the improved photocatalytic activity of the designed Z-scheme system.