Visible Light Photoactivity Research Articles

The Efficient Coupling between MgAlTi Layered Double Hydroxides and Graphitic Carbon Nitride Boosts Vis Light‐Assisted Photocatalytic NOx Removal

AbstractAtmospheric pollution has been recognized as a primary global emergency, especially in large cities and industrial areas. Among the most common harmful pollutants, nitrogen oxides (NOx) are responsible for a plethora of adverse effects, and their effective elimination from air has become an imperative task. In this regard, photocatalysis stands as an attractive technology for NOx degradation, provided that low‐cost and efficient visible ‐light photocatalysts are developed. In this regard, the construction of heterojunctions between energy band‐matched semiconductors is an effective strategy to boost the ultimate material photoactivity. In the present study, green heterocomposites based on MgAlTi layered double hydroxides (LDHs) and graphitic carbon nitride (gCN) are prepared using an amenable and cost‐effective route. A proper modulation of the system characteristics, as demonstrated by a comprehensive investigation, enabled to obtain very attractive DeNOx performances thanks to the efficient construction of MgAlTi/gCN heterojunctions with tailored features. The formation of the target heterocomposites significantly enhances the visible light photoactivity of the pristine LDH, boosting nitrogen monoxide transformation to nitrites/nitrates with a remarkable recycling stability. Overall, the presently reported results open the door to a profitable system exploitation for air purification under real‐world conditions, with considerable impact on both human wellbeing and environmental protection.

Substitutional Cu doping at the cation sites in Ba2YNbO6 toward improved visible-light photoactivity—A first-principles HSE06 study

Artificial photosynthesis holds immense promise for sustainable clean energy harvesting, with recent strides in material engineering with the earth abundant elements enabling efficient utilization of the visible solar spectrum for photoelectrochemical catalytic water splitting. Here, we have investigated the impact of substitutional Cu doping at all three cation sites in Ba2YNbO6 (BYN) using density functional theory calculations at the Heyd-Scuseria-Ernzerhof-06 level. One of the key findings is that the defect formation energy follows the hierarchy Nb > Ba > Y. The presence of an oxygen vacancy (OV) enhances the co-solubility of Cu substitution of Nb, particularly when placed outside the CuO6 unit, while it has a contrary effect for Y substitution. Cu replacement reduces the bandgap as Nb > Y ≫ Ba vis-à-vis pure BYN, while extending it into the visible part of the solar spectrum for Nb and Y replacement cases, albeit with OV causing a slight blue shift to them, without reducing the oxidation state of Cu due to strong charge-delocalization. Cu doping at Y and Nb sites retains the direct band transition character of BYN, a feature removed by OV. While all the bare Cu doped systems exhibit formation of a weak electron polaron, the placement of OV tends to annihilate this except for the system comprising first nearest neighbor placement of an OV relative to the Cu substitution at an Nb site. Notably, Cu doping at the Nb site significantly enhances optical activity, particularly ∼2.0–2.5 eV, resulting in promising candidates for photoelectrochemical catalysts.

Effect of Nitrogen Doping on the Photocatalytic Properties and Antibiofilm Efficacy of Reduced TiO2 Nanoparticles.

Nanomaterial-mediated antibacterial photodynamic therapy (aPDT) emerges as a promising treatment against antibiotic-resistant bacterial biofilms. Specifically, titanium dioxide nanoparticles (TiO2 NPs) are being investigated as photosensitizers in aPDT to address biofilm related diseases. To enhance their photocatalytic performance in the visible spectral range for biomedical applications, various strategies have been adopted, including reduction of TiO2 NPs. However, despite improvements in visible-light photoactivity, reduced TiO2 NPs have yet to reach their expected performance primarily due to the instability of oxygen vacancies and their tendency to reoxidize easily. To address this, we present a two-step approach to fabricate highly visible-light active and stable TiO2 NP photocatalysts, involving nitrogen doping followed by a magnesium-assisted reductive annealing process. X-ray photoelectron spectroscopy analysis of the synthesized reduced nitrogen-doped TiO2 NPs (H:Mg-N-TiO2 NPs) reveals that the presence of nitrogen stabilizes oxygen vacancies and reduced Ti species, leading to increased production of reactive oxygen species under visible-light excitation. The improved aPDT efficiency translates to a 3-fold enhancement in the antibiofilm activity of nitrogen-doped compared to undoped reduced TiO2 NPs against both Gram-positive (Streptococcus mutans) and Gram-negative (Porphyromonas gingivalis, Fusobacterium nucleatum) oral pathogens. These results underscore the potential of H:Mg-N-TiO2 NPs in aPDT for combating bacterial biofilms effectively.

Evaluation of antifungal activity of visible light-activated doped TiO2 nanoparticles.

Titanium dioxide (TiO2) is a well-known material for its biomedical applications, among which its implementation as a photosensitizer in photodynamic therapy has attracted considerable interest due to its photocatalytic properties, biocompatibility, high chemical stability, and low toxicity. However, the photoactivation of TiO2 requires ultraviolet light, which may lead to cell mutation and consequently cancer. To address these challenges, recent research has focused on the incorporation of metal dopants into the TiO2 lattice to shift the band gap to lower energies by introducing allowed energy states within the band gap, thus ensuring the harnessing of visible light. This study presents the synthesis, characterization, and application of TiO2 nanoparticles (NPs) in their undoped, doped, and co-doped forms for antimicrobial photodynamic therapy (APDT) against Candida albicans. Blue light with a wavelength of 450nm was used, with doses ranging from 20 to 60J/cm2 and an NP concentration of 500µg/ml. It was observed that doping TiO2 with Cu, Fe, Ag ions, and co-doping Cu:Fe into the TiO2 nanostructure enhanced the visible light photoactivity of TiO2 NPs. Experimental studies were done to investigate the effects of different ions doped into the TiO2 crystal lattice on their structural, optical, morphological, and chemical composition for APDT applications. In particular, Ag-doped TiO2 emerged as the best candidate, achieving 90-100% eradication of C. albicans.

Bismuth sulfide-impregnated cobalt oxide nanocrystals: An enhanced photocatalyst for improved hydrogen production beneath visible light

Hydrogen (H2) is the lightest and greenest fuel compared to conventional energy resources. The production of H2 could be achieved via several techniques as renewable energy sources. Due to its simplicity, the visible-light H2 evolution over nanocomposite photocatalysts is an emerging method. Following this, the surfactant-aided sol–gel way has grown Cobalt oxide (Co3O4) nanoparticles. 3.0–12.0 wt% of bismuth sulfide (Bi2S3) nanocrystals were added to Co3O4 by impregnating technique to enhance the visible-light photoactivity. The produced nanostructures were utilized to generate H2 by photocatalytic reaction in a water/glycerol medium with platinum traces cocatalyst. The impregnation of Bi2S3 at 9.0 wt% has endorsed the photogenerated H2 by ∼ 8.7 folds (∼1547 µmol g−1 h−1) than only using bare Co3O4 (∼178 µmol g−1 h−1) owing to bandgap reduction down to 1.71 eV and suppression of charge recombination. The dose control of 2.5 gL−1 has augmented the H2 generation to 3.095 mmol g−1 h−1 with a significant regeneration to reach 96.5 % after the fifth run. The improved performance of the formed 9.0 % Bi2S3/Co3O4 heterojunction is accredited to the enhanced photocharge separation between Bi2S3 and Co3O4.

Highly active Pd nanoparticles decorated on benzene‐ring doped g‐C3N4 as catalyst in methylene Blue degradation and Cr (VI) ions reduction

The development of simply prepared, highly active and reusable nanocatalysts for methylene blue degradation (MB) or Cr (VI) ions reduction under sunlight conditions in wastewater remains a challenge in the field of green chemistry. Addressed herein is the catalyst of Pd(0) nanoparticles supported on benzene ring doped graphitic carbon nitride (Pd@BD‐g‐C3N4) for MB degradation or Cr (VI) ions reduction under visible light irradiation. Pd@BD‐g‐C3N4 nanocatalyst has been synthesized using the facile wet impregnation–chemical reduction method to boost the catalytic efficiency of BD‐g‐C3N4. The MB degradation or Cr (VI) ions reduction proceeded efficiently in the presence of Pd@BD‐g‐C3N4. Compared with pure BD‐g‐C3N4 in both studies, the hybrid photocatalyst Pd@BD‐g‐C3N4‐exhibited enhanced visible light photoactivity was higher than of pure BD‐g‐C3N4. In addition, in the reusability tests, it was observed that the Pd@BD‐g‐C3N4 photocatalyst has good stability and repeated cycle performance. The electronic and morphologic structure of support material and nanocatalyst were characterized by several techniques such as FT‐IR, DR/UV‐Vis, BET, SEM‐EDX, HR‐TEM, P‐XRD, and XPS analyses.

Cobalt Oxide on Boron-Doped Graphitic Carbon Nitride as Bifunctional Photocatalysts for CO2 Reduction and Hydrogen Evolution.

In this work, the prepared cobalt oxide decorated boron-doped g-C3N4 (CoOx/g-C3N4) heterojunction exhibits remarkable activity in CO2 reduction (CO2RR), resulting in high yields of CH3COOH (∼383 μmol·gcatalyst-1) and CH3OH (∼371 μmol·gcatalyst-1) with 58% selectivity to C2+ under visible light. However, the same system leads to high H2 evolution (HER) by increasing the cobalt oxide content, suggesting that the selectivity and preference for the CO2RR or HER depend on oxide decoration. By comparing HER and CO2RR evolution in the same system, this work provides critical insights into the catalytic mechanism, indicating that the CoOx/g-C3N4 heterojunction formation is necessary to foster high visible light photoactivity.

A mechanistic evaluation for total removal of toxic hexavalent and trivalent chromium from water by oxygen vacancy-engineered nanocomposite

Oxygen vacancy-engineered nanocomposites are emerging materials in adsorption and photocatalysis research. This study evaluated total toxic Chromium removal by a nanocomposite of core-shell zeolite A@oxygen-vacant ZnO1−X (ZA@ZnO1−X) from water using its coexisting dual characteristics. ZA@ZnO1−X has removed 98.3% of total Cr, achieving a discharge limit of 0.05 ppm of Cr(VI) after the photoreduction and adsorption simultaneously. The detailed structural and physicochemical properties of synthesized ZA@ZnO1−X nanocomposite show higher BET surface area, oxygen-vacant percentage, and visible light photoactivity than the sole ZnO1−X nanosheet. The photocatalytic reduction efficiency (PRE) effect is systematically studied on varying operational variables like pH, citric acid (CA), Cr(VI) concentration, catalyst load, presence of anions, and radical scavengers. ZA@ZnO1−X removed Cr(VI) and Cr(III) simultaneously by 98.5% PRE with a catalyst load of 4 g/l, CA= 5 mM, pH= 5.06 under halogen light irradiation (300 W, 240 V) for 50 mins. This experimental study evaluates the prominent role of oxygen vacancy of ZA@ZnO1−X for photocatalytic reduction of Cr(VI) and enhanced adsorption of Cr(III). The kinetic study reveals adsorption of both Cr(VI) and Cr(III) follows pseudo-second-order kinetics, whereas photoreduction of Cr(VI) follows pseudo-first-order kinetics. A possible mechanism of total Cr removal is sketched, supporting enhanced adsorption due to unsaturated Zn atoms and unpaired e- at the oxygen defect site, followed by photoreduction by photogenerated e- and CO2-• radical. The ZA@ZnO1−X performance is reduced by only 2.5% after five consecutive runs without deformation. The easy regeneration process makes it suitable for toxic total Cr removal, avoiding any secondary pollution.

Effect of annealing temperature on the formation of oxygen vacancies on the surface of flower-like SnSe/SnO2 heterostructure and visible light catalytic performance

The morphology, structure, and oxygen vacancies in principle determine the light absorption, charge transfer, and separation of photocatalysts, thereby determining their photocatalytic performance. In this study, flower-like SnSe obtained from hydrothermal reactions was oxidized to obtain heterojunctions with SnSe/SnO2. Flower-like SnSe/SnO2 heterojunctions with different concentrations of oxygen vacancies were prepared by annealing them in an argon atmosphere at different temperatures. The flower-like SnSe/SnO2 series with different oxygen vacancies were systematically characterized by TEM, XRD, XPS, PL, and EPR. The research results demonstrate the presence of oxygen vacancies in the flower-like SnSe/SnO2. As the annealing temperature increases, the surface oxygen vacancy concentration shows a trend of first increasing and then decreasing. When the annealing temperature reaches 600 °C, the oxygen vacancy concentration of flower-like SnSe/SnO2 is the highest. Meanwhile, research has shown that surface oxygen vacancies help expand the light absorption range, and the increased valence bandwidth leads to effective charge transfer and separation, thereby promoting visible light photoactivity. SnSe/SnO2-600 °C exhibited excellent visible light photocatalytic activity. The photodegradation of methylene blue (MB) at ≥ 400 nm can reach ∼70% within 120 min. This study verified the route for the introduction of oxygen vacancies via facile calcination and constructed SnSe/SnO2 with surface oxygen vacancies, providing a reference with deep insights for improving photocatalytic activity.

Fe-doped BiVO4 photocatalyst assisting SnO2 nanorod arrays for efficient visible-light-driven degradation of Basic Red 46

BackgroundDesigning and constructing heterogeneous structures is an effective approach employed to improve photocatalytic performance. This study aimed to use Fe-doped BiVO4/SnO2 nanocomposites for photocatalytic degradation of Basic Red 46 (BR46) dye under visible-light irradiation. MethodsBiVO4 nanoparticles doped with varying amounts of Fe were synthesized using the sol-gel method and interspersed on SnO2 nanorods with an average diameter of about 100 nm fabricated using the liquid phase deposition (LPD) process. FE-SEM, EDX, XRD, FT-IR, XPS, BET, DRS, and PL analysis were used to characterize the morphology and structure of the samples. Significant findingsThe 1.5 wt% Fe-doped BiVO4/SnO2 nanocomposite exhibited the highest visible-light photoactivity with excellent stability, resulting in complete degradation of BR46 within 90 min of irradiation. The boost photocatalytic activity of Fe-doped BiVO4/SnO2 nanocomposite can be attributed to the enhanced separation of photo-generated carriers derived from synergistic effects by the BiVO4/SnO2 heterostructure, Fe doping in BiVO4 lattice, and partly the extended light absorption ability. These findings show that designing a heterogeneous BiVO4/SnO2 structure with Fe-doping can be a promising strategy for the application in constructing efficient and stable photocatalysts for the degradation of dyes from industrial wastewater pollutions.

Synthesis, structural and microstructural properties of Bismuth Vanadate BiVO4

Metal vanadates MVO4 demonstrate exceptional visible-light photo-activity due to their desirable properties, including high responsiveness to visible light, a narrow bandgap, affordability, non-toxicity, chemical stability, resistance to corrosion, low environmental impact, and the ability to control their morphology. In this study, BiVO4 phase was synthesized without the use of surfactants through a coprecipitation process followed by calcination at 500 °C. The synthesized oxides were initially analyzed using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The structural and morphological characterization indicated that BiVO4 exhibited a monoclinic crystalline phase. The crystal cell of BiVO4 was found to be monoclinic, with parameters a, b, c, and β, and belonging to the I2/b space group. SEM images revealed the presence of spherical-like crystallites with a consistent local nominal composition of BiV.

Visible light photoactivity of the Cu doped TiO2/Yb2O3 nanocomposite for degradation of acid red 88 solution

Visible light photoactivity of the Cu doped TiO2/Yb2O3 nanocomposite for degradation of acid red 88 solution

Role of BaTiO3 crystal surfaces on the electronic properties, charge separation and visible light–response of the most active (001) surface of LaAlO3: A hybrid density functional study

Surface engineering has been proved as an efficient technique to boost charge separation and visible light absorption of semiconductor photocatalyst materials. Herein, we offer a first insight into the photocatalytic properties and electronic structure of cubic LaAlO3(001) modified with cubic BaTiO3 (001), (011) and (111) surfaces. Compared to the bulk LaAlO3, the BaTiO3/LaAlO3(001) heterostructures showed superior redshift of absorption, work functions and a suitable staggered type–II band alignment to separate the photoinduced carriers. The BaTiO3(001) surface coupled with LaAlO3(001) surface show improved visible light photoactivity owing to the more surface complex and terminal barium atoms forming the main active adsorption sites on its surface. These findings offer new insight into the understanding of preferential exposure of photocatalytic active surfaces, which will aid in designing active heterostructures for photocatalytic reactions, as well as understanding the mechanism of photocatalysis.

Easy three steps gC3N4 exfoliation for excellent photocatalytic activity – An in-depth comparison with conventional approaches

Producing an ultrathin nanostructure through exfoliation of carbon nitride (gC3N4) significantly enhances the photoactivity of the material. However, the influence of the exfoliation method on the properties and photocatalytic activity of gC3N4 nanosheets is still poorly understood. In this study, conventional methods such as thermal, chemical and ultrasonic exfoliation of gC3N4 nanosheets have been compared with a three-step exfoliation method. The three-step exfoliation strategy allows the control of the microstructure, light absorption property, morphology and visible light photoactivity of gC3N4 nanosheets. Products show a superior photocatalytic efficiency under simulated sunlight compared to gC3N4 nanosheets obtained with conventional exfoliation methods. Degradation kinetics of this material are also superior. gC3N4 nanosheets prepared by three-step exfoliation exhibit a high specific surface area, optimal band gap energy structure, higher electron density and more efficient charge separation than products of conventional exfoliation methods. This new three-step exfoliation strategy is an easy way for obtaining high performance gC3N4 nanosheets for water purification.

Efficient visible light activities of Ag modified ZnO/g-C3N4 composite for CO2 conversion

• Designing unique system based on Ag/ZnO/g-C 3 N 4 . • Charge separation and transfer mechanism discussion. • Photocatalytic CO 2 conversion to CO/CH4. Methane and CO have superior economic value and application panorama compared with other products, and these are the ideal products of CO 2 photo-reduction. However, low CO 2 conversion efficiency and poor selectivity are huge obstacles to its practical application. Herein, we develop a three-component photocatalyst hetero-junction of Ag-ZnO/g-C 3 N 4 for superior CO 2 reduction. It is demonstrated that the amount-optimized nanocomposite exhibited exceptional visible-light photoactivities for CO 2 conversion to CO, with ≈ 9-time (36 µmol g −1 h −1 ) enhancement compared to the widely accepted g-C 3 N 4 prepared from melamine as the raw material. Similarly, the silver-modified samples exhibit a considerable increase in methane production, with 14 µmol g −1 h −1 , which is significantly more than the CH 4 production of 2 µmol g −1 h −1 by pure g-C 3 N 4 . Based on the photo-physical data, it is concluded that the coupled ZnO, which accepts electrons and improves reactant adsorption, and the modified Ag, which further promotes the photocatalytic reaction, are much more responsible for the high photoactivities. Moreover, it is suggested based on the photocatalytic experiments with isotopic 13 CO 2 that the produced • CO 2 as active radicals dominated the conversion of CO 2 to CO/CH 4 . This work provides a feasible strategy to design high-performance, low-cost, and sustainable g-C 3 N 4 -based nanocomposite photo-catalysts with a wide range of visible light activity for CO 2 reduction.

Synthesis and characterization of porous TiO2 film decorated with bilayer hematite thin film for effective photocatalytic activity

• Fe 2 O 3 was successfully deposited onto porous TiO 2 by simple and developed electrochemicaltechnique. • TiO 2 /bilayer hematite film has good stability and the high specific surface area. • The as-prepared porous photocatalysts Fe 2 O 3 /TiO 2 show high visible light photoactivities for the degradation of the methylene blue dye. In this work, porous TiO 2 film decorated with bilayer hematite (nanoparticles/nanorods) were synthesized via the electrodeposition technique followed by hydrothermal treatment. Structural and morphological properties of the TiO 2 /bilayer hematite films were determined by X-ray diffraction (XRD), Also with energy dispersive X-ray spectral (EDS), and scanning electron microscopy (SEM). Due to its good stability and the high specific surface area, TiO 2 /bilayer hematite film, as a potential absorber film, can be applied to enhance organic dye degradation. The photodegradation of the porous, thin film trijunction was remarkable under visible light and normal pH.

Efficient Oxygen Vacancy Defect Engineering for Enhancing Visible-Light Photocatalytic Performance over SnO2-x Ultrafine Nanocrystals.

Regardless of its good electron-transfer ability and chemical stability, pure Zn2SnO4 (ZSO) still has intrinsic deficiencies of a narrow spectral response region, poor absorption ability, and high photo-activated carrier recombination rate. Aiming to overcome the deficiencies above-mentioned, we designed a facile hydrothermal route for etching ZSO nanoparticles in a dilute acetic acid solution, through which efficient oxygen vacancy defect engineering was accomplished and SnO2−x nanocrystals were obtained with an ultrafine particle size. In comparison with the untreated ZSO nanoparticles, the specific surface area of SnO2−x nanocrystals was substantially enlarged, subsequently leading to the notable augmentation of active sites for the photo-degradation reaction. Aside from the above, it is worth noting that SnO2−x nanocrystals were endowed with a broad spectral response, enhancing light absorption capacity and the photo-activated carrier transfer rate with the aid of oxygen vacancy defect engineering. Accordingly, SnO2−x nanocrystals exhibited significantly enhanced photoactivity toward the degradation of the organic dye rhodamine B (RhB), which could be imputed to the synergistic effect of increasing active sites, intensified visible-light harvesting, and the separation rate of the photo-activated charge carrier caused by the oxygen vacancy defect engineering. In addition, these findings will inspire us to open up a novel pathway to design and prepare oxide compound photocatalysts modified by oxygen vacancy defects in pursuing excellent visible-light photoactivity.

Visible‐Light Photocatalytic and Photo‐bactericidal Activity of Ni‐CuWO4/OTiO2 Composite†

Comprehensive SummaryA series of nickel‐doped copper tungstate/oxygen‐rich TiO2 heterojunction‐constructed composites of xNi‐CuWO4/OTiO2 were successfully prepared to demonstrate the enhancement of the visible‐light photoactivity through promoting the photogenerated charge carrier separation efficiency. Of all these composites, 0.2Ni‐CuWO4/OTiO2 exhibits excellent and stable visible light photoactivity for the photooxidative coupling of benzylamine to the corresponding N‐benzyl‐1‐phenymethanimine (BPMI) in air atmosphere. The conversion of benzylamine and the selectivity to BPMI reach 97% and 99%, respectively. The catalyst shows good cyclability with the conversion of benzylamine decreasing just by 22% after being repeated six times with the well‐maintained selectivity of BPMI. The composite also exhibits excellent photo‐bactericidal ability, which greatly inhibits the reproducing of both the Gram‐positive bacteria (e.g., S. epidermidis) and Gram‐negative bacteria (e.g., E. coli).

Photocatalytic abatement of formaldehyde under visible light irradiation via bamboo carbon/TiO2 modified by plasma at low temperature

A new catalyst modified by plasma was investigated to substantively improve the photoactivity of TiO2 for formaldehyde abatement. Pure anatase TiO2 mechanically mixed with biochar was fabricated by H2 plasma (denoted as C/TiO2) under low temperatures (<397 K). C/TiO2 exhibited a high and long-lasting activity and remove approximately 73.7% of formaldehyde within 3 h under a simulated visible light irradiation; this is much higher the corresponding values using untreated TiO2 and untreated mixtures (denoted as un-C/TiO2). It is concluded that, following H2 plasma treatment, the addition of 5% biochar to the catalyst had the best removal efficiency due to increased meso/microporous structures, a decreasing bandgap and diminishing recombination rate of electron–hole pairs. During the process, the surface active-oxygen groups including –OH increased from 19% to 24%. These results also reveal that the catalyst could be etched by high-energy electrons in order to gain better surface properties for formaldehyde degradation. This new plasma-assisted catalyst has enhanced visible light photoactivity and a boosted capture ability and could thus have promising applications to volatile organic compounds.

Enhancement of visible-light photo-activity of TiO2 arrays for environmental water purification

PurposeOver the past decades, intense efforts have been devoted to design and synthesize efficient photocatalysts which are active under sunlight for environmental and energy applications. Titanium dioxide (TiO2) has attracted much attention over many years for organic contaminant degradation in air or water due to its strong optical absorptivity, chemical stability and low cost. However, TiO2 has a very low photo quantum yield which prompts the easy recombination of photogeneration electron/hole pairs. In addition, bandgap of 3.2 eV restrains application of this photocatalyst mainly to the UV range.Design/methodology/approachVertically oriented one-dimensional TiO2 nanostructures remarkably improve electron transport by creating a direct conduction pathway, decreasing intercrystalline contacts and stretching grown structure with the specified directionality. In this research, to enhance the visible light absorbance of TiO2, prearranged hydrogenated titanium dioxide nanorods (H-TNRs) in the presence of H2/N2 gas flow are hydrothermally synthesized.FindingsThe X-ray diffraction patterns illustrated the characteristic peaks of tetragonal rutile TiO2 and confirmed that there is no phase change after hydrogenation. Trivalent titanium ions surface defects and oxygen vacancies were considered as major reasons for redshift of absorption edge toward visible region and subsequently narrowing the bandgap to 2.27 eV. The optimized photocatalysts exhibited high visible-light-driven photocatalytic activity for degradation of methylene blue in water within 210. The synthesized H-TNRs established themselves as promising photocatalysts for organic compounds degradation in the aqueous solution.Originality/valueTo the best of the authors’ knowledge, this work is original and has not been published elsewhere nor is it currently under consideration for publication elsewhere.