Anatase Phase Stability Research Articles

Synthesis and characterization of TiO2/ZnO/SiO2 nanocomposite using pyrrolidinium-based ionic liquids via sol–gel-hydrothermal method for photocatalytic removal of Pb (II) ions

This study aims to synthesize TiO2 with precise particle morphology, a large surface area, a stable anatase phase at high temperatures, and enhanced catalytic activity in the visible light spectrum. TiO2 was combined with ZnO and SiO2 to form a TiO2/ZnO/SiO2 composite (TZS). A TiO2/ZnO/SiO2 composite (TZS) was synthesized via sol–gel-hydrothermal method at 180 °C for 24 h employing a water-pyrrolidinium-based ionic liquid mixture. XRD analysis confirmed anatase, zincite, and amorphous silica phases post-calcination at 450 °C. Compared to water alone, TZS synthesized with the water-ILs media exhibited higher surface area and narrower band gap energy. TG-DTA analysis confirmed anatase phase stability up to 1000 °C. SEM and TEM images showed TZS particles synthesized using water as spherical, while the water-ILs mixture produced nanocoral, nanorod, and nanocubic morphologies. In photocatalysis, TZS synthesized with water-ILs removed Pb(II) ions by 99.98 %, surpassing water-synthesized TZS at 95.49 % indicating superior photocatalytic of TZS synthesized with water-ILs.

Synthesis of TiO2-SiO2-Ag/Fiberglass with Antibacterial Properties and Its Application for Air Cleaning.

The TiO2-SiO2-Ag/fiberglass with antibacterial properties under UV light irradiation was synthesized. The effects of compositions of TiO2-SiO2-Ag/fiberglass, optical, and textural characteristics on the antibacterial activity were studied. The TiO2-SiO2-Ag film was coated on the surface of fiberglass carrier filaments. The temperature effect on the formation of the TiO2-SiO2-Ag film was established by thermal analysis, and the temperature treatment mode was selected as 300 °C for 30 min, 400 °C for 30 min, 500 °C for 30 min, and 600 °C for 30 min. The influence of silicon oxide and silver additives on the antibacterial properties of TiO2-SiO2-Ag films was established. Increasing the treatment temperature of the materials up to 600 °C increased the thermal stability of the titanium dioxide anatase phase, while the values of optical characteristics decreased: the film thickness decreased to 23.92 ± 1.24 nm, the refractive index decreased to 2.154 ± 0.002, the energy of the band gap width decreased to 2.8 ± 0.5, and the light absorption shifted to the visible-light regime, which is important for photocatalytic reactions. The results showed that the use of TiO2-SiO2-Ag/fiberglass allows significant decrease in the value of CFU microbial cells to 125 CFU m-3.

Synthesis and evaluation of photocatalytic properties of Na–TiO2/Sr4All4O25:Eu,Dy phosphor composites

Sub-micron Sr4Al14O25:Eu,Dy phosphor particles were coated by a TiO2-sol precipitation procedure at 80 °C for 3 h. The effects of Na/H2O2 additives on TiO2 precipitation and stability of the composites over heat treatment conditions were evaluated. The distribution of TiO2 nanoclusters on the sub-micron phosphor support changed from sparse to dense clusters with increasing Na additive. X-ray diffraction and Raman spectroscopy analyses revealed that the anatase and rutile phases dominated in the Na–TiO2/phosphor nanocomposites at 300 °C. Heat treatment at 450 °C was detrimental to the stability of TiO2 anatase phase. Ultraviolet and visible light were utilized for photocatalytic decomposition of methylene blue and toluene volatile organic components in the vicinity of the Na–TiO2/phosphor composites. Optimum photocatalytic performances were obtained in TiO2/phosphor composites with low concentration precipitation additives (1% Na and 0.23 vol% H2O2) heat-treated at 300 °C. Anatase phases and Na+ existence in TiO2/Sr4Al14O25:Eu,Dy phosphor composites improved the light sensitization and overall photocatalytic efficiencies.

Block Copolymer and Cellulose Templated Mesoporous TiO2-SiO2 Nanocomposite as Superior Photocatalyst

A dual soft-templating method was developed to produce highly crystalline and mesoporous TiO2-SiO2 nanocomposites. Pluronic F127 as the structure-directing agent and pure cellulose as the surface area modifier were used as the templating media. While Pluronic F127 served as the sacrificing media for generating a mesoporous structure in an acidic pH, cellulose templating helped to increase the specific surface area without affecting the mesoporosity of the TiO2-SiO2 nanostructures. Calcination at elevated temperature removed all the organics and formed pure inorganic TiO2-SiO2 composites as revealed by TGA and FTIR analyses. An optimum amount of SiO2 insertion in the TiO2 matrix increased the thermal stability of the crystalline anatase phase. BET surface area measurement along with low angle XRD revealed the formation of a mesoporous structure in the composites. The photocatalytic activity was evaluated by the degradation of Rhodamine B, Methylene Blue, and 4-Nitrophenol as the model pollutants under solar light irradiation, where the superior photo-degradation activity of Pluronic F127/cellulose templated TiO2-SiO2 was observed compared to pure Pluronic templated composite and commercial Evonik P25 TiO2. The higher photocatalytic activity was achieved due to the higher thermal stability of the nanocrystalline anatase phase, the mesoporosity, and the higher specific surface area.

Influence of Cu-doped TiO2 on its structural and photocatalytic properties

Due to the potential of heterogeneous photocatalysis for wastewater treatment, the researches concerning the improvement materials modifications for its photocatalytic activity have been widely increased. One of the most employed methods is the metal doping into semiconductors. Herewith, we demonstrated the influence of Cu doping into TiO2 in its photocatalytic properties. The powder samples with 0.0 to 0.7% mol were obtained by the Pechini method and characterized by XRD, micro-Raman spectroscopy, FE-SEM, and photoluminescence spectroscopy. The Cu insertion into TiO2 structure induced the stabilization of anatase phase, increasing its content in the samples in relation to the bare TiO2. The PL results indicated that a decrease in the PL emission intensity and a shift of the emission band to the blue region. The photocatalytic activity for rhodamine B degradation under UV light irradiation indicated that the Cu-doping into TiO2 led to an enhancement of the photocatalytic activity compared to the bare one.

Oxidation behavior of TiCr and TiMo alloys formed by low-energy pulsed electron beam impact

The titanium-based alloys with 2–3 at.% of chromium (TiCr) and molybdenum (TiMo) were produced on the top of titanium samples by means of the high-intense pulsed electron beam impact on the titanium with preliminary deposited Cr and Mo coatings. The TiCr and TiMo alloys were subjected to oxidation in open air atmosphere at temperature 600 °C. X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and energy-disperse X-ray microanalysis (EDX) were used for structure and elemental composition determination in the samples. The analysis of oxygen depth profiles showed the increase in oxygen penetration depth in the case of TiCr alloy in comparable to pure titanium. The oxygen concentration corresponding to stoichiometry of the oxide phase TiO2 was found on the depth equaled to the thickness of the TiCr alloy that shows the enhancement of the diffusion of oxygen in the modified layer. The diffusion of oxygen at the temperature of 600 °C is enhanced by decomposition of the solid solutions based on bcc β-Ti phase with free chromium and molybdenum atoms releasing. The free molybdenum atoms take part in the stabilization of TiO2 anatase phase while the free chromium atoms form intermetallic compound TiCr2 preventing the sample from oxidation.

Mechanical characterization of spark plasma sintered titania‐silicon oxycarbide (TiO2/SiOC) nanocomposites

AbstractIn this work, titania‐silicon oxycarbide nanocomposites synthesized via the polymer derived ceramics route have been sintered into crack‐free monoliths using spark plasma sintering and their mechanical properties as well as their apparent density have been characterized. The x‐ray diffractogram clearly showed the stabilization of anatase phase of size less than 10 nm size in an amorphous silicon oxycarbide matrix at 1200 °C. The hardness and elastic modulus determined using nanoindentation were found to be 9 GPa and 82 GPa, respectively, and the fracture toughness calculated using indentation crack length method was found to be 2.34 MPa m1/2. In addition to this, ball‐on‐three ball technique was used to evaluate the biaxial flexural strength and fractographic studies were carried out to understand the fracture mechanisms.

Dimensional constraints favour high temperature anatase phase stability in TiO2 nanorods

High temperature stable anatase phase TiO2 nanostructures have the potential to advance the fields such as photocatalysis, solar cells and batteries. However, it is challenging to grow TiO2 nanostructures that can retain the anatase phase at high temperatures. Here, we report slanted TiO2 nanorods grown on Si substrates by glancing angle deposition technique employing electron beam evaporation to showcase the anatase phase stability up to 800 °C. FESEM surface morphology shows that the nanorods started deforming above 600 °C and collapsed at 800 °C. We carried out image processing of the nanorods assembly and quantified the deformation with annealing temperature. The x-ray diffraction and Raman spectroscopy utilized for the phase information showed that the anatase phase is stable even at 800 °C. Further, we have studied the effect of deformation on wettability of the nanorods system and found that annealed samples are superhydrophilic. Remarkably, the annealed TiO2 nanorods have transformed to hydrophobic when kept in the dark storage due to the structural contribution to contact angle rather than surface energy. Notably, the hydrophobicity increases with time, which was studied for 25 months. The stable high temperature anatase phase could find application in the solar cells, photocatalysis, smart windows, self-cleaning coatings, etc.

Luminescence improvement of (Ti,Si)O2:Eu3+/Li+ spherical particles for anti-counterfeiting application

Eu3+-doped TiO2 as a security material was synthesized by spray pyrolysis. The effect of the SiO2 introduction and Li + co-doping on the crystallographic and optical properties of TiO2:Eu3+ were investigated as changing the calcination temperature. TiO2:Eu3+ has an intense peak at 618 nm due to the electrical dipole transition 5D0 → 7F2 of Eu3+ located in a site without inversion symmetry. The SiO2 introduction suppressed the grain growth of TiO2 and improved the thermal stability of anatase phase. Thus, (Ti,Si)O2:Eu3+ could have a larger band gap while maintaining anatase phase at higher calcination temperature and showed an improved emission of about 38% compared to TiO2:Eu3+. In addition, the co-doping of Li+ with Eu3+ into the (Ti,Si)O2 matrix was found to be an effective way to substantially improve PL intensity due to the charge compensation effect. As a result, (T,Si)O2:Eu3+/Li+ showed about 143% enhanced luminescence intensity compared to TiO2:Eu3+, and was confirmed to have high luminescence under near-ultraviolet light when applied to the logo mark.

Efficient Zr-doped FS–TiO2/SiO2 photocatalyst and its performance in acrylonitrile removal under simulated sunlight

The aim of this research is to develop an efficient photocatalyst for the degradation of acrylonitrile under simulated sunlight. In this work, Zr-doped FS–TiO2/SiO2 photocatalyst was reported for the degradation of acrylonitrile. Sol–gel method were used for the preparation of Zr-doped FS–TiO2/SiO2 with the molar ratio of Ti:Zr varied from 1:0.07. The prepared photocatalyst was calcined at 450 °C for 2 h. The characteristics of Zr-doped FS–TiO2/SiO2 were examined by X-ray diffraction (XRD), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) and X-ray photoelectron spectroscopy (XPS). XRD results confirmed the presence of anatase phase of TiO2, and it also reveals that the Zr doping did not change the crystal phase of TiO2. The absorbance of Zr-doped FS–TiO2/SiO2 was significantly enhanced, as confirmed by the red shift in UV–Vis DRS spectra. Zr doping inhibits the recombination of electron–hole pairs and enhanced the photocatalytic activity. The UV–Vis DRS spectra show stronger absorption in Zr-doped FS–TiO2/SiO2 photocatalysts compared to FS–TiO2/SiO2. XPS analysis illustrated the presence of Zr4+, Ti3+, Ti4+, O2− and OH groups in Zr-doped FS–TiO2/SiO2. Then, the photocatalytic activity of the prepared photocatalyst was tested for the photocatalytic degradation of acrylonitrile under simulated sunlight. Zr doping, together with F and S would enhance the surface area and charge separation, making it serve as a more effectual photocatalyst than TiO2 and FS–TiO2/SiO2. The degradation ratio of acrylonitrile reached 79.2% within 6 min of simulated sunlight due to the doping effect of Zr into FS–TiO2/SiO2 photocatalyst. Zr doping could enhance the thermal stability of anatase phase of TiO2 and improve its surface properties.

Mo doped TiO2: impact on oxygen vacancies, anatase phase stability and photocatalytic activity

This work outlines an experimental and theoretical investigation of the effect of molybdenum (Mo) doping on the oxygen vacancy formation and photocatalytic activity of TiO2. Analytical techniques such as x-ray diffraction (XRD), Raman, x-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) were used to probe the anatase to rutile transition (ART), surface features and optical characteristics of Mo doped TiO2 (Mo–TiO2). XRD results showed that the ART was effectively impeded by 2 mol% Mo doping up to 750 °C, producing 67% anatase and 33% rutile. Moreover, the crystal growth of TiO2 was affected by Mo doping via its interaction with oxygen vacancies and the Ti–O bond. The formation of Ti–O–Mo and Mo–Ti–O bonds were confirmed by XPS results. Phonon confinement, lattice strain and non-stoichiometric defects were validated through the Raman analysis. DFT results showed that, after substitutional doping of Mo at a Ti site in anatase, the Mo oxidation state is Mo6+ and empty Mo-s states emerge at the titania conduction band minimum. The empty Mo-d states overlap the anatase conduction band in the DOS plot. A large energy cost, comparable to that computed for pristine anatase, is required to reduce Mo–TiO2 through oxygen vacancy formation. Mo5+ and Ti3+ are present after the oxygen vacancy formation and occupied states due to these reduced cations emerge in the energy gap of the titania host. PL studies revealed that the electron–hole recombination process in Mo–TiO2 was exceptionally lower than that of TiO2 anatase and rutile. This was ascribed to introduction of 5s gap states below the CB of TiO2 by the Mo dopant. Moreover, the photo-generated charge carriers could easily be trapped and localised on the TiO2 surface by Mo6+ and Mo5+ ions to improve the photocatalytic activity.

Effect of chalcogens (S, Se, and Te) on the anatase phase stability and photocatalytic antimicrobial activity of TiO2

The effect of chalcogens such as sulphur (S), selenium (Se), and tellurium (Te) on the anatase to rutile phase transition (ART) of titanium dioxide (TiO2) was investigated. 2 mol % of chalcogen doped TiO2 was synthesised via a sol–gel technique. The as-synthesised samples were calcined at different temperatures from 500 °C to 800 °C for 2 h. X-ray diffraction (XRD) and Raman spectroscopy were used to study the ART of TiO2. Te -TiO2 showed the highest anatase phase (44%) at 750 °C as compared to other samples. X-ray photoelectron spectroscopy (XPS) and UV–visible diffuse reflectance spectroscopy (UV-DRS) was further utilised to investigate the oxidation state and optical properties. UV-DRS results showed that the substitutional doping of chalcogens in the TiO2 lattice enhanced visible light absorption. The photocatalytic efficiency was tested for the disinfection of Escherichia coli (E.coli) under visible light irradiation. It is noted that while the chalcogen modified TiO2 improved the anatase stability the antimicrobial activity is not significantly enhanced compared to pure anatase TiO2 under visible light illumination. Te-TiO2 attained 100% disinfection within 70 min of visible light irradiation and maintained equal antibacterial efficiency as pure TiO2 at 750 °C.

Firmness and bandgap engineered anatase TiO2 nanoparticles for enhanced visible light photocatalytic activity

Titanium dioxide is a standard semiconductor material plays a vital role in environmental and energy research. Anatase to rutile phase transformation in pure TiO2 nanoparticles usually occurs in the temperature range 600 °C–700 °C with it only absorbs UV light, owing to its large bandgap of 3.2 eV. Till date, researchers and industrialists have been trying to synthesize TiO2 nanoparticles with increased anatase phase stability with reducing the bandgap of pure anatase phase to the visible region, used dopant or H2O2 precursor modification, but the long time has taken photocatalytic activity under sunlight. Here, using a novel Photon Induce Method (PIM) has reported extending the anatase to a rutile transformation temperature, which in turn reflects on the stability of the material. PIM prepared oxygen-rich TiO2 nanoparticles exhibit enhanced temperature stable anatase phase, i.e. the sample remained as pure anatase phase even after calcinating at 1000 °C with a reduced bandgap of less than 2.91 eV, stretching towards the red region of the sunlight, whereas the standard Degussa P25-TiO2 and Others are reported to exist as 100% rutile at this temperature. By tuning the oxygen vacancy preparation conditions, we can reversibly improve oxygen-rich Titania via PIM. The absence of dopant or H2O2 of pure Titania anatase nanoparticles is high chemical reactivity has important implications for antibacterial, cancer cells kill, photocatalysis and solar energy conversion.

Investigation on the phase transformation and lattice parameters of Sn2+, Cu2+, La3+ and Ce4+ ions doped titania: characterization and solar light activity study

Nanocrystalline titania and metal ion doped titania systems were prepared by combustion method. Titania exhibited bicrystalline phase consisting of both anatase and rutile. The bicrystalline framework in TiO2 powders can be conveniently altered by the incorporation of various bivalent/trivalent/tetravalent metal ions like Sn2+, Cu2+, La3+and Ce4+. The microstructure development and the influence of small amount of dopants on the resulting structural change have been investigated. p-XRD results confirms the stabilization of anatase phase in the case of Cu2+ and Sn2+ doped titania, while the polymorphic interfaces were retained in La3+and Ce4+ doped titania samples. The efficacy of the modified titania was studied on the degradation of Congo Red dye by harvesting solar light. Sn2+/TiO2 shows almost same photodegradation ability as that of pristine TiO2. Subsistence of catalytic hot spots at the interface of anatase-rutile and the synergistic effect of polymorphic phases explains the enhanced activity of La3+/TiO2 and Ce4+/TiO2. But the activity of Cu2+/TiO2 was found to be less due to high electron-hole recombination rate.

Zirconium doped mesoporous TiO2 multilayer thin films: Influence of the zirconium content on the photodegradation of organic pollutants

Though applications of TiO2 thin films in environmental pollution remediation are promising, up to date, photocatalytic efficiency is still a challenge. Herein, we report enhanced photocatalytic activity of mesoporous TiO2 thin films towards degradation of organic pollutants in water due to their modification with zirconium. Highly stable, uniform transparent thin films were prepared using evaporation induced self-assembly via dip-coating. The effects of Zr addition on the morphology, structure, crystallinity and photoactivity of the catalyst were investigated. Incorporation of Zr to Ti lattice positions in the TiO2 anatase crystals increased stability of anatase phase and enhanced the charge separation as confirmed by photoluminescence measurements. X-ray diffraction analysis proved the formation of ZrO2 as additional phase for Zr/Ti ratios above 0.1. The resulting nanocomposite formation influences the crystallite size as well as the N2 adsorption of the films.Optimized Zr doped TiO2 thin films with a Zr/Ti ratio of 0.05 showed almost complete photocatalytic degradation of chloridazon, phenol and 4-chlorophenol within 4 h of illumination; pure TiO2 thin films recorded much lower activities for all these pollutants.

Xerogel Solvothermal in Different Alcohols of Cu and N Codoped TiO2 Powders: Characterization Photocatalytic Oxidation of Acetone

In this study, mesoporous Cu and N co-doped TiO2 crystals were synthesized with Cu and N co-doped titania xerogel by solvothermal treatment in different alcohols and the characteristics of Cu and N co-doped TiO2 were investigated with XRD, SEM, UV-vis and N2 sorption analysis. Results indicated that different alcohols facilitated formation and stability of pure anatase phase. The photocatalytic activity of samples was evaluated by the photocatalytic oxidation of acetone under visible light.The extraordinary photocatalytic performance of the Cu and N co-doped TiO2 crystals were synthesized with titania xerogel by solvothermal treatment in ethyl alcohol. This enhanced photoactivity is related to the bandgap narrowing, good dispersibility, the smaller pores and the larger specific area. DOI: http://dx.doi.org/10.5755/j01.ms.24.4.18568

Direct nanocrystallite size investigation in microstrained mixed phase TiO2 nanoparticles by PCA of Raman spectra

Mixed phase anatase and rutile TiO2 nanoparticles (30–67% R/A) have been synthesized by single step laser pyrolysis. Parallel studies by XRD and Raman spectroscopy suggested possible deforming microstress inside certain samples, due to boundary interactions between neighbouring nanocrystallites in nanoparticles, phase instabilities and/or O/C contents. Microstress in nanoparticles supports anatase phase stability in competition with rutile phase. Williamson-Hall plot was used to evaluate crystallite size and strain. A tensile global microstrain in anatase crystallites, was observed for elevated C content titania nanoparticles, together with compressive microstrain in crystallites within O deficient TiO2 nanoparticles. XPS and TEM characterization opens insights regarding the processes behind this type of behaviour. Principal Component Analysis of Raman spectra was applied for batch auto-characterization of mixed phase nanoparticles, with emphasis upon the method ability to simultaneously appreciate crystallite size for both anatase and rutile phase. The method focuses on covariational matrix of multiple samples Raman spectra. It provides results in good agreement with XRD calculated crystallite dimensions for unstrained titania, while for samples with microstrains it returns the size closer to the one predicted by Williamson-Hall plot.

Tuning the optical band Gap of pure TiO2 via photon induced method

Titanium dioxide, a well known photocatalyst will become more useful if it utilizes visible light. Many efforts have been made to achieve the utilization of visible light by TiO2 for photocatalytic activity by changing the preparation methods or by doping various transition metals. Herein, a novel Photon Induced Method (PIM) is being proposed to produce oxygen-rich TiO2 with modified optical band gap and high stability. The prepared TiO2 nanoparticles have been subjected to various characterizations such as XRD, HRSEM, HRTEM, FTIR, UV–vis and PL. XRD results reveal that as the calcination temperature is increased, the crystallite size of the TiO2 nanoparticles is seen to increase. Also, the XRD results reveal an increase in pure anatase phase stability upto 750 °C when compared to earlier reports of pure anatase phase stability upto 650 °C. HRTEM analysis shows the formation of nanosized bullet like structure. A narrowing of optical band gap to 3.09 eV is evident through UV–vis absorption studies. This tuning of band gap is expected to facilitate the absorption of visible light. The photocatalytic activity of the prepared TiO2 nanoparticles has also been studied. The results reveal that TiO2 nanoparticles prepared by this novel method exhibit an increased photocatalytic activity when compared to the standard Degussa P25 sample reported earlier.

Cu-Doped TiO2: Visible Light Assisted Photocatalytic Antimicrobial Activity

Surface contamination by microbes is a major public health concern. A damp environment is one of potential sources for microbe proliferation. Smart photocatalytic coatings on building surfaces using semiconductors like titania (TiO2) can effectively curb this growing threat. Metal-doped titania in anatase phase has been proven as a promising candidate for energy and environmental applications. In this present work, the antimicrobial efficacy of copper (Cu)-doped TiO2 (Cu-TiO2) was evaluated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) under visible light irradiation. Doping of a minute fraction of Cu (0.5 mol %) in TiO2 was carried out via sol-gel technique. Cu-TiO2 further calcined at various temperatures (in the range of 500–700 °C) to evaluate the thermal stability of TiO2 anatase phase. The physico-chemical properties of the samples were characterized through X-ray diffraction (XRD), Raman spectroscopy, X-ray photo-electron spectroscopy (XPS) and UV–visible spectroscopy techniques. XRD results revealed that the anatase phase of TiO2 was maintained well, up to 650 °C, by the Cu dopant. UV–vis results suggested that the visible light absorption property of Cu-TiO2 was enhanced and the band gap is reduced to 2.8 eV. Density functional theory (DFT) studies emphasize the introduction of Cu+ and Cu2+ ions by replacing Ti4+ ions in the TiO2 lattice, creating oxygen vacancies. These further promoted the photocatalytic efficiency. A significantly high bacterial inactivation (99.9999%) was attained in 30 min of visible light irradiation by Cu-TiO2.

Stabilization of anatase phase by uncompensated Ga-V co-doping in TiO2: A structural phase transition, grain growth and optical property study

Uncompensated Ga-V co-doped TiO2 samples have been prepared by modified sol-gel process. Inhibition of phase transition due to co-doping is confirmed by X-ray diffraction measurement. Activation of phase transition increases from 120 kJ/mol (x = 0) to 240 kJ/mol (x = 0.046) due to Ga-V incorporation. In anatase phase, lattice constant increases by the effect of Ga3+ interstitials. This results in inhibition of phase transition. Anatase phase becomes stable up to ~ 650 °C in co-doped sample whereas for pure TiO2 phase transition starts in between 450 and 500 °C. High-resolution transmission electron microscope image shows particle size decreases in anatase phase due to co-doping. Increasing strain due to Ga-V incorporation results in reducing crystallite size. Brunauer–Emmett–Teller analysis shows that surface increases from 4.55 m2/g (pure TiO2) to 96.53 m2/g (x = 0.046) by Ga-V incorporation. In rutile phase, grain growth process is enhanced mainly due to the effect of Vanadium and particles show a rod-like structure with majority {110} facets. Bandgap decreases in both phases and reduced to visible light region. For charge balance in uncompensated Ga-V co-doped sample, structural distortion created in the lattice by combining effect of substitution, interstitials and oxygen vacancies, which results in stabilization of anatase phase and reducing of bandgap.