Nitrogen-doped Titanium Research Articles

Electrospun PVDF/PVP Fibrous Membrane with Photocatalytic and Superhydrophilic Properties.

Membrane separation technology is used to treat environmental wastewater, but during the treatment process, the occurrence of membrane fouling greatly affects the treatment efficiency. To address this phenomenon, improve membrane antipollution capabilities, and treat organic wastewater, photocatalysis and membrane separation technology have been coupled, forming a suitable and promising treatment method. Here, we propose a simple strategy to prepare a polyvinylidene fluoride/polyvinyl pyrrolidone nitrogen-doped titanium dioxide fibrous membrane (PVDF/PVP N-doped TiO2 fibrous membrane). The experimental results showed that PVDF and PVP mixed spinning made the fibrous membrane have a unique microstructure, and the superhydrophobic PVDF fibrous membrane was changed into superhydrophilic. In addition, electrospraying technology was used to attach TiO2 nanoparticles (NPs) to the fiber, and nitrogen (N) was doped in this process to improve the photocatalytic activity of the fibrous membrane. Finally, methyl blue solution was used as the target organic pollutant. Under the irradiation of a xenon lamp, 90.05% of methyl blue was removed within 90 min, indicating that the membrane had good photocatalytic performance. In a water contact angle test, the PVDF/PVP N-doped TiO2 fibrous membrane showed superhydrophilicity. The design of a fibrous membrane with high photocatalytic activity and superhydrophilicity properties has great potential for practical application in the purification of industrial wastewater.

Photocatalytic degradation of phenol and polycyclic aromatic hydrocarbons in water by novel acid soluble collagen-polyvinylpyrrolidone polymer embedded in Nitrogen-TiO2

Herein, we have synthesized acid-soluble collagen (ASC), polyvinylpyrrolidone (PVP), and nitrogen-doped titanium dioxide to form a novel hybrid photocatalyst nanocomposite (N-TiO2/ASC-PVP). The results of XRD, SEM and TEM revealed that the as-synthesized photocatalyst was composed of spheroidal particles, which were smaller than undoped TiO2.XPS analysis revealed that N was effectively incorporated into the lattice of TiO2 through substituting oxygen atoms, and N might coexist in the form of substitutional N (O–Ti–N) and interstitial N (TiON). The N-TiO2/ASC-PVP composite calcined at 200 and 400 °C exhibited high photocatalytic degradation rates for phenol, naphthalene (Nap), fluoranthene (Flu), phenanthrene (Phe), pyrene (Pyr), benz[a]anthracene (BaA), and anthracene (Ana), achieving a 98.6 % removal rate within 120 min at a dosage of 10 mg/L. The enhanced visible light photocatalytic activity was mainly attributed to the smaller crystal size, more surface hydroxyl groups, stronger light absorption in visible region and narrower band gap energy. This innovative hybrid photocatalyst holds immense potential for applications in materials science and nanotechnology, promising to revolutionize various industries.

Synthesis, Performance Measurement of Dy2EuSbO7/ZnBiDyO4 Heterojunction Composite Catalyst and Photocatalytic Degradation of Chlorpyrifos within Pesticide Wastewater under Visible Light Irradiation

For the first time, a novel catalyst named Dy2EuSbO7 was successfully synthesized via the high-temperature solid-state sintering method (HTSSM). Dy2EuSbO7/ZnBiDyO4 heterojunction photocatalyst (DZHP) was fabricated through the HTSSM for degrading chlorpyrifos (CPS) in the pesticide wastewater under visible light irradiation (VSLID). Under VSLID, DZHP could effectively degrade CPS in pesticide wastewater. The experimental outcomes suggested that the kinetic curve with the Dy2EuSbO7/ZnBiDyO4 heterojunction (DZH) as a photocatalyst for the reduction of CPS under VSLID conformed to the first-order kinetics (FOKT). After VSLID of 156 min, the photocatalytic degradation (PTD) removal rate of CPS using DZH as photocatalyst was 1.12 times, 1.21 times, or 2.96 times that using Dy2EuSbO7 as a photocatalyst, ZnBiDyO4 as a photocatalyst, or nitrogen-doped titanium dioxide as a photocatalyst. After VSLID of 156 min for four cycle degradation tests (FCDTS) with DZH as a photocatalyst, the removal rate of CPS reached 98.78%, 97.66%, 96.59%, and 95.69%, respectively. Above results indicated that the DZHP possessed high stability. Experiments with the addition of trapping agents showed that hydroxyl radicals (•OH) owned the strongest oxidative removal ability for degrading CPS compared with superoxide anions (•O2−) or holes (h+). The oxidation capacity of three oxidation radicals for eliminating CPS was ranked in the ascending order as follows: h+ < •OH < •O2−. Lastly, the possible degradation pathway and degradation mechanism of CPS were discussed in detail. A visible light responsive heterojunction catalyst with high catalytic activity and a photocatalytic reaction system which were capable of efficiently removing toxic organic pollutants from pesticide wastewater were obtained.

A novel graphene-N/TiO2-nickel foam: Preparation and application in photoelectric synergistic degradation of methyl orange

Photoelectric synergistic degradation of dye wastewater has been developed. In this experiment, we prepared Nitrogen-doped titanium dioxide-graphene/nickel foam (N/TiO2-Gr/F–Ni) by electrophoresis and impregnation methods, to degrade methyl orange (MO) aqueous solution. Firstly, nitrogen-doped titanium dioxide particle (N/TiO2) was prepared by the sol-gel method, which showed a photocatalytic degradation catalytic kinetic constant of 1.8 × 10−2 min−1 under simulated sunlight. Meanwhile, graphene (Gr) was loaded on nickel foam (F–Ni) to prepare Gr/F–Ni electrode by electrophoresis method, which obtained a catalytic kinetic constant of 1.15 × 10−2 min−1 at 10 V. Finally, N/TiO2 was loaded on Gr/F–Ni to prepare N/TiO2-Gr/F–Ni photoelectrode by electrophoresis and impregnation methods, which had a catalytic kinetic constant of 3.96 × 10−2 min−1 at 10 V and under 1 sun. The results show that there is a synergistic effect between light degradation and electro-Fenton oxidation because the bonding electrons in N/TiO2 are activated to produce photogenerated electron-hole pairs. On the other hand, the separation efficiency of the photogenerated electron is enhanced by the Gr.

Photocatalytic Reduction of Perrhenate and Pertechnetate in a Strongly Acidic Aqueous Solution.

Pertechnetate (99TcO4-), a physiologically toxic radioactive anion, is of great concern due to its high mobility in environmental contamination remediation. Although the soluble oxyanion can be photoreduced to sparingly soluble TcO2·nH2O, its effective removal from a strongly acidic aqueous solution remains a challenge. Here, we found that low-crystalline nitrogen-doped titanium oxide (N-TiO2, 0.6 g L-1) could effectively uptake perrhenate (ReO4-, 10 mg L-1, a nonradioactive surrogate for TcO4-) with 50.8% during 360 min under simulated sunlight irradiation at pH 1.0, but P25 and anatase could not. The nitrogen active center formed by trace nitrogen doping in N-TiO2 can promote the separation and transfer of photogenerated carriers. The positive valence band value of N-TiO2 is slightly higher than those of P25 and anatase, which means that the photogenerated holes have a stronger oxidizability. These holes are involved in the formation of strong reducing •CO2- radicals from formic acid oxidation. The active radicals convert ReO4- to Re(VI), which is subsequently disproportionated to Re(IV) and Re(VII). Effective photocatalytic reduction/removal of Re(VII)/Tc(VII) is performed on the material, which may be considered a potential and convenient strategy for technetium decontamination and extraction in a strongly acidic aqueous solution.

Optimization of an ultra-bright real-time high-throughput renilla luciferase assay for antibacterial assessment of Streptococcus mutans biofilms

ObjectiveThe present work demonstrates the optimization of a renilla-based real-time, ultra-bright, non-disruptive, high-throughput bioluminescence assay (HTS) to assess the metabolism of intact Streptococcus mutans biofilms and its utility in screening the antibacterial efficacy of experimental nanofilled dental adhesive resins containing varying concentrations of nitrogen-doped titanium dioxide nanoparticles (N_TiO2). Methods. Optimization of the assay was achieved by screening real-time bioluminescence changes in intact Streptococcus mutans biofilms imposed by the various experimental biofilm growth parameters investigated (bacterial strain, growth media, sucrose concentration, dilution factor, and inoculum volume). The optimized assay was then used to characterize the antibacterial efficacy of experimental nanofilled dental adhesive resins. The assay’s ability to discriminate between bacteriostatic and bactericidal approaches was also investigated. Results. Relative Light Units (RLU) values from the HTS optimization were analyzed by multivariate ANOVA (α = 0.05) and coefficients of variation. An optimized HTS bioluminescence assay was developed displaying RLUs values (brightness) that are much more intense when comparing to other previously reported bioluminescence assays, thereby decreasing the error associated with bioluminescence assays and displaying better utility while investigating the functionalities of antimicrobial nanofilled experimental dental adhesive resins with proven long-term properties. Significance. The present study is anticipated to positively impact subsequent research on dental materials and oral microbiology because it serves as a valuable screening tool in metabolic-based assays with increased sensitivity and robustness. The assay reported is anticipated to be further optimized to be used as a co-reporter for other Luc based assays.

Solar-powered detection of organic dyes using nitrogen-doped N-TiO2/Ag2O nanorod arrays.

Organic pollutant detection has caused widespread concern regarding due to their potential environmental and human health risks. In this work, a nitrogen-doped titanium dioxide/silver oxide (N-TiO2/Ag2O) composite has been designed asa sensitive photoelectrochemical (PEC) monitoring platform of organic dyes. Sensitive determination relies on the outstanding PEC performance of N-TiO2/Ag2O. The improved PEC performance stems from the effective separation of photocarriers and the extended light response range provided by the narrowing bandgap and a p-n junction with N-TiO2/Ag2O. The N-TiO2/Ag2O electrode exhibits a photocurrent density of up to 2.2mA/cm2, demonstrating three times increase compared withthe photocurrent density observed with the pure TiO2 film. The linear detection range for rhodamine B (RhB), methylene blue (MB), and methyl orange (MO) is 0.2ng/mL to 10 μg/mL with an ultrasensitive detection limit of 0.2ng/mL without bias voltage. Due to the outstanding photocurrent density and sensitive response to organic pollutants, the N-TiO2/Ag2O PEC sensor provided a promising analytical method to detect environmental organic dyes.

Functionalization of niobium nitrogen-doped titanium dioxide (TiO2) nanoparticles with ethanolic extracts of Mentha arvensis.

Titanium dioxide (TiO2) nanoparticles have gained significant attention due to their wide-ranging applications. This research explores an approach to functionalize Niobium Nitrogen Titanium Dioxide nanoparticles (Nb-N-TiO2 NPs) with Mentha arvensis ethanolic leaf extracts. This functionalization allows doped NPs to interact with the bioactive compounds in extracts, synergizing their antioxidant activity. While previous studies have investigated the antioxidant properties of TiO2 NPs synthesized using ethanolic extracts of Mentha arvensis, limited research has focused on evaluating the antioxidant potential of doped nanoparticles functionalized with plant extracts. The characterization analyses are employed by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Ultraviolet-visible (UV-Vis) spectroscopy to evaluate these functionalized doped nanoparticles thoroughly. Subsequently, the antioxidant capabilities through the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP) assays have been assessed. Within functionalized Nb-N-TiO2, the FTIR has a distinctive peak at 2350, 2010, 1312, 1212, and 1010cm-1 with decreased transmittance associated with vibrations linked to the Nb-N bond. SEM revealed a triangular aggregation pattern, 500nm to 2µm of functionalized Nb-N-TiO2 NPs. Functionalized doped Nb-N-TiO2 NPs at 500µgmL-1 exhibited particularly robust antioxidant activity, achieving an impressive 79% efficacy at DPPH assessment; meanwhile, ferric reduction efficiency of functionalized doped Nb-N-TiO2 showed maximum 72.16%. In conclusion, doped Nb-N-TiO2 NPs exhibit significantly enhanced antioxidant properties when functionalized with Mentha arvensis ethanolic extract compared to pure Nb-N-TiO2 manifested that doped Nb-N-TiO2 have broad promising endeavors for various biomedicine applications.

Characterization of novel solar based nitrogen doped titanium dioxide photocatalytic membrane for wastewater treatment

The increasing presence of microbial and emerging organic contaminants pose detrimental effects on the environment and ecosystem such as diseases, pandemics and toxicity. Most of these synthetic pollutants are biorecalcitrant and therefore persist in the environment. Conventional water treatment methods are not effective thereby necessitating the development of advanced techniques such as photocatalysis and membrane processes. In this study, visible light-driven photocatalytic membrane was synthesized through the immobilization of nitrogen-doped nanoparticles onto the polyvinylidene fluoride (PVDF) membrane and performance evaluated with E.coli microbial contaminant removal. Characterization was done using Fourier transform infrared spectra, X-ray diffraction (XRD), water contact angle, Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX). The Nitrogen-doping of titanium dioxide red-shifted the light absorption to a visible range of 440 nm from 400 nm. Nitrogen dopant was detected at 1420 cm−1and 1170 cm−1 for nitrogen doped nanoparticles and 1346-1417 cm−1 for nitrogen doped titanium dioxide PVDF membrane. SEM-EDX confirmed presences of nitrogen in nitrogen doped titanium dioxide nanoparticles on membrane surface with nitrogen elemental composition of 0.01 % wt. The water contact angle reduced by 81.39o from 120.14o to 38.75o because of PVA immobilization of nitrogen-doped titanium dioxide and glutaraldehyde crosslinking. Nitrogen doping resulted in visible light active photocatalytic membranes with better hydrophilicity and fouling resistance. 8.42 E.coli log removal and a relative flux of 0.35 was obtained within 75 min. The developed photocatalytic membrane enables the use of sunlight hence a less costly method for decontamination of wastewater.

Functionalization of niobium nitrogen-doped titanium dioxide (TiO2) nanoparticles by using Mucuna pruriens methanolic extracts

Functionalization of niobium nitrogen-doped titanium dioxide (TiO2) nanoparticles by using Mucuna pruriens methanolic extracts

Enhanced Aluminum-Ion Storage Properties of N-Doped Titanium Dioxide Electrode in Aqueous Aluminum-Ion Batteries.

Aqueous aluminum-ion batteries (AIBs) have great potential as devices for future large-scale energy storage systems due to the cost efficiency, environmentally friendly nature, and impressive theoretical energy density of Al. However, currently, available materials used as anodes for aqueous AIBs are scarce. In this study, a novel sol-gel method was used to synthesize nitrogen-doped titanium dioxide (N-TiO2) as a potential anode material for AIBs in water. The annealed N-TiO2 showed a high discharge capacity of 43.2 mAh g-1 at a current density of 3 A g-1. Analysis of the electrode kinetics revealed that the N-TiO2 anodes exhibited rapid diffusion of aluminum ions, low resistance to charge transfer, and high electronic conductivity, enabling good rate performance. The successful implementation of a nitrogen-doping strategy provides a promising approach to enhance the electrochemical characteristics of electrode materials for aqueous AIBs.

Preparation and Property Characterization of Eu2SmSbO7/ZnBiEuO4 Heterojunction Photocatalysts and Photocatalytic Degradation of Chlorpyrifos under Visible Light Irradiation

Eu2SmSbO7 and ZnBiEuO4 were synthesized for the first time using the hydrothermal method. Eu2SmSbO7/ZnBiEuO4 heterojunction photocatalyst (EZHP) was synthesized for the first time using the solvothermal method. The crystal cell parameter of Eu2SmSbO7 was 10.5547 Å. The band gap width of Eu2SmSbO7 was measured and found to be 2.881 eV. The band gap width of ZnBiEuO4 was measured and found to be 2.571 eV. EZHP efficiently degraded the pesticide chlorpyrifos under visible light irradiation (VLID). After VLID of 160 min, the conversion rate of the chlorpyrifos concentration reached 100%, while the conversion rate of the total organic carbon (TOC) concentration was 98.02% using EZHP. After VLID of 160 min, the photocatalytic degradation conversion rates of chlorpyrifos using EZHP were 1.13 times, 1.19 times, and 2.84 times those using Eu2SmSbO7, ZnBiEuO4, and nitrogen-doped titanium dioxide (N-doped TiO2), respectively. The photocatalytic activity could be ranked as follows: EZHP > Eu2SmSbO7 > ZnBiEuO4 > N-doped TiO2. The conversion rates of chlorpyrifos were 98.16%, 97.03%, 96.03%, and 95.06% for four cycles of experiments after VLID of 160 min using EZHP. This indicated that EZHP was stable and could be reused. In addition, the experiments with the addition of capture agents demonstrated that the oxidation removal ability of three oxidation free radicals for degrading chlorpyrifos obeyed the following order: hydroxyl radical > superoxide anion > holes. This study examined the intermediates of chlorpyrifos during the photocatalytic degradation of chlorpyrifos, and a degradation path was proposed, at the same time, the degradation mechanism of chlorpyrifos was revealed. This study provides a scientific basis for the development of efficient heterojunction photocatalysts.

TiO2/PDA Multilayer Nanocomposites with Exceptionally Sharp Large-Scale Interfaces and Nitrogen Doping Gradient.

The evolving field of photocatalysis requires the development of new functional materials, particularly those suitable for large-scale commercial systems. One particularly promising approach is the creation of hybrid organic/inorganic materials. Despite being extensively studied, materials such as polydopamine (PDA) and titanium oxide continue to show significant promise for use in such applications. Nitrogen-doped titanium oxide and free-standing PDA films obtained at the air/water interface are particularly interesting. This study introduces a straightforward and reproducible approach for synthesizing a novel class of large-scale multilayer nanocomposites. The method involves the alternate layering of high-quality materials at the air/water interface combined with precise atomic layer deposition techniques, resulting in a gradient nitrogen doping of titanium oxide layers with exceptionally sharp oxide/polymer interfaces. The analysis confirmed the presence of nitrogen in the interstitial and substitutional sites of the TiO2 lattice while maintaining the 2D-like structure of the PDA films. These chemical and structural characteristics translate into a reduction of the band gap by over 0.63 eV and an increase in the photogenerated current by over 60% compared with pure amorphous TiO2. Furthermore, the nanocomposites demonstrate excellent stability during the 1 h continuous photocurrent generation test.

Nitrogen-Doped Titanium Dioxide for Selective Photocatalytic Oxidation of Methane to Oxygenates.

Photocatalytic conversion of methane (CH4) to value-added chemicals using H2O as the oxidant under mild conditions is a desired sustainable pathway for synthesizing commodity chemicals. However, controlling product selectivity while maintaining high product yields is greatly challenging. Herein, we develop a highly efficient strategy, based on the precise control of the types of nitrogen dopants, and the design of photocatalysts, to achieve high selectivity and productivity of oxygenates via CH4 photocatalytic conversion. The primary product (methanol) is obtained in a high yield of 159.8 μmol·g-1·h-1 and 47.7% selectivity, and the selectivity of oxygenate compounds reached 92.5%. The unique hollow porous structure and substituted nitrogen sites of nitrogen-doped TiO2 synergistically promote its photo-oxidation performance. Furthermore, in situ attenuated total reflectance Fourier transform infrared spectroscopy provides direct evidence of the key intermediates and their evolution for producing methanol and multicarbon oxygenates. This study provides insights into the mechanism of photocatalytic CH4 conversion.

Photocatalytic Self-cleaning Eco-Friendly Paint: A Unique Approach for Efficient Indoor Air Pollutant Removal and Surface Disinfection

Improving of air quality, particularly the removal of indoor-air pollutants with direct environmental and health implications, remains a significant challenge in modern society. We, herein, present a novel approach using photocatalytic eco-friendly paint to effectively eliminate indoor air pollutants and disinfect surfaces. Ultra Small Porous Nitrogen-doped Titanium dioxide (USPNT), which has been successfully incorporated into the paint by different coating techniques. The UPSNT photocatalyst was synthesized via probe sonication coupled sol-gel technique, resulting in anatase phase with a high surface area of 83m²/g. The efficiency of the UPSNT-coated paint in removing air pollutant like p-xylene under simulated indoor illumination is considered. In additional, it showed the capability to disinfect pathogens like E. coli, remove surface dirt, such as organic dyes, confirming its self-cleaning properties. This will lead to develop a direct eco-friendly paint by formulating USPNT directly with suitable binders promotes the durability of indoor and outdoor air quality as well as reducing “sick building syndrome’’.

Nitrogen-doped titanium dioxide as a novel eco-friendly hole transport layer in lead-free CsSnI3 based perovskite solar cells

After an abrupt rise in the efficiency of perovskite solar cells (PSCs), hole transport layer (HTL) as an essential factor for fabricating efficient PSC devices attract attentions. The pristine spiro-OMeTADspiro-OMeTAD, as most widely used HTL, still suffers from poor electrical conductivity, low hole mobility, and low oxidation rate. In this research, the spiro-OMeTAD is replaced by nitrogen doped TiO2 (N-TiO2) HTL. Then, the variation in the device design key parameters such as the thickness and bulk defect density of perovskite layer, simultaneous modifications of defect density and defect energy level, and acceptor doping concentration in absorber layer, and operating temperature are examined with their impact on the photovoltaic characteristic parameters. The standard lead-free CsSnI3–based PSCs with spiro-OMeTAD HTL is simulated using SCAPS-1D software. The CsSnI3-based solar cell with N-TiO2 as HTL showed higher efficiency of 27.03 % than the standard device with PCE of 23.63 % for conventional spiro-OMeTAD HTL.

Photocatalytic effect of N–TiO2 conjugated with folic acid against biofilm-forming resistant bacteria

Antibiotic resistance challenges the treatment of bacterial biofilm-related infections, but the use of nanoparticles as a treatment is a promising strategy to overcome bacterial infections. This study applied nitrogen-doped titanium dioxide (N–TiO2) conjugated with folic acid (FA) on biofilm-forming resistant bacteria. The photocatalytic effect of TiO2 nanoparticles (NPs) was studied under ultraviolet (UV), visible light, and dark conditions at 60, 120, and 180 min against planktonic cells and biofilms of Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa. TiO2 NPs were in the anatase phase, spherical shaped with sizes of 10-13 nm, and effectively doped and conjugated with N and FA. The FA-conjugated nanoparticles (N–TiO2-FA and FA-TiO2) were shown to have a bactericidal effect on all bacteria between 60 and 180 min under UV and visible light conditions. Concerning biofilms, N–TiO2-FA was shown to have a highly disruptive effect on all bacterial biofilms under UV irradiation at 180 min. Meanwhile, the nanoparticles did not show DNA damaging potential and they had no cytostatic effect, indicating that these NPs are biocompatible. In sum, nanoparticle conjugation with FA promoted photocatalytic effectiveness, revealing the promise this nanomaterial holds as a biocompatible antimicrobial agent.

Synthesis of N-doped TiO2 nanoparticles with enhanced photocatalytic activity for 2,4-dichlorophenol degradation and H2 production

Nitrogen-doped titanium dioxide (N-TiO2) nanoparticles were prepared using a modified sol-gel method. The as-prepared nanoparticles were characterized by state-of-the-art techniques for their optical, structural and morphological properties. The crystallite size, surface area and bandgap energy of reference TiO2 and N-TiO2 nanoparticles were found to be 16.1 and 10.9 nm, 83.6 and 131.8 m2 g−1 and 3.23 and 2.89 eV, respectively. The photocatalytic activities, in terms of 2,4-dichlorophenol (2,4-DCP) degradation, of reference TiO2 and N-TiO2 were found to be 46.9% and 65.4% at 120 min of treatments under UV light irradiation and 21.5% and 77.6% at 240 min of treatment under visible light irradiation, employing 153.4 µM 2,4-DCP, 1 g/L photocatalyst dosage, and pH 5.6. Interestingly, considerable H2 production rate (i.e., 386 μmol h−1 g−1) was observed for visible/N-TiO2 system in presence of 0.2 wt% Pt. The study revealed that visible/N-TiO2 photocatalytic system can be used as an economically viable technology for environmental sustainability.

Photocatalytic performance of nitrogen-doped titanium dioxide nanostructures prepared by sol-gel method

A sol-gel method was used to prepare nitrogen-doped titanium dioxide nanoparticle using tetrabutyl titanate as the titanium source and urea as the nitrogen source. The structure and properties of the samples were characterized by modern testing methods. The photocatalytic performance of N-doped titanium dioxide nanoparticle was evaluated by taking Polyacrylic amide (PAM) in the wastewater from petroleum extraction as the target degradation product. The results show that, after N-nano TiO2 is calcined at 650 °C, the TiO2 is mainly of anatase type, with a large amount of rutile titanium dioxide nanoparticle between the crystals, and the average grain size decreases from 25.9 nm to 16.8 nm. Under visible light, the removal rate of N-TiO2 on PAM simulated wastewater for 3 h was determined to have been 59% and this is increased to 79.8%. After the photocatalyst was regenerated by ultraviolet irradiation, the removal rate of pollutants still reached 74.2%.

Visible light-assisted efficient degradation of Rhodamine B by N-TiO2/Mn-HPMo/Ag ternary composites

In this paper, Ag nanoparticles were deposited on the surface of nitrogen-doped titanium dioxide coupled with manganese-substituted phosphomolybdic acid composites (N-TiO2/Mn-HPMo) using photoreduction method to construct ternary photocatalysis-Fenton composite catalyst (N-TiO2/Mn-HPMo/Ag), and the degradation performance of the catalyst was evaluated with Rhodamine B (RhB) as the target pollutant. The results showed that the N-TiO2/Mn-HPMo/Ag ternary composite catalyst had remarkable visible light activity, and the degradation efficiency of RhB could reach 96.3% in 20 min under visible light. Meanwhile, UV–vis diffuse reflectance spectroscopy illustrated the promotion effect of Ag deposition on the visible light response of N-TiO2/Mn-HPMo. The behavior of photogenerated charges was also characterized by Surface Photovoltage Technique, which further demonstrated that Ag deposition not only extended the light absorption range but also enhanced the separation efficiency of photogenerated charges. This work provides favorable information for the construction of efficient catalysts with high activity under visible light.