TiO2 Films Research Articles

Nanostructure of TiO\(_{2}\) and WO\(_{3}\) multilayer films deposited on ITO glass for electrochromic enhanced photocatalytic activity

The photocatalytic activity (PA) by electrochromic (EC) enhancement of single and multilayer films of TiO2, WO3, TiO2/WO3, and WO3/TiO2 was investigated. All films were deposited from metal on an ITO glass substrate using direct current (DC) magnetron sputtering via an oblique angle deposition (OAD) technique at 85°. Subsequently, a thermal oxidation (TO) process at 500℃ was applied for the samples to form metal oxide films. The morphology, elemental composition, crystal structure, and optical properties were studied by using field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffractometry (XRD), and UV-vis spectroscopy, respectively. The photocatalytic properties were investigated by showing the degradation rate of methylene blue (MB) solution as an organic pollutant that was examined under ultraviolet irradiation of 300 µW∙cm‒2. The film samples were investigated by comparing the pre-color and colored states that were achieved through the EC process. The EC properties of WO3 led to increased charge insertion on the film surface. This observation was further supported by cyclic voltammetry (CV) testing, which revealed a higher current density for the thin film samples. The photodegradation results showed that the samples in the colored state exhibited a significantly higher degradation rate of MB compared to the pre-color state.

Enhancing the anti-tarnish and mechanical properties of gold-coated silver sheets for decorative applications using TiO2 film protection

This study explores an innovative method to enhance the anti-tarnish and mechanical properties of gold-coated silver sheets, targeting decorative applications through the TiO2 film coatings. The research focuses on gold films with a thickness of approximately 100 nm, and TiO2 films ranging from 10 to 31 nm. It was observed that the color of the multilayer coatings exhibited significant sensitivity to variations in thickness, indicating that a TiO2 coating with a thickness around 20 nm could be optimally applied to the gold film, maintaining an acceptable ΔE value. X-ray photoelectron spectroscopy analysis demonstrated the TiO2 film’s potential to inhibit the formation of Ag2S on the surface, thereby enhancing tarnish resistance. Furthermore, the application of a 20 nm TiO2 layer reduced the friction coefficient from 0.28 to 0.24 for gold-coated silver. Durability tests involving 1,000 abrasion cycles revealed that the gold film without TiO2 protection experienced delamination, with only about 57 % of the coated area remaining intact. In contrast, the samples protected with a TiO2 layer retained approximately 90 % of the coating, underscoring the effectiveness of TiO2 in preserving the structural integrity and appearance of the gold-coated silver sheets.

The synthesis, characterization, and thermal properties of a titanium (III) amidinate compound and its potential as a single chemical vapor deposition precursor for N/C-doped TiO2 film

A titanium(III) amidinate compound had been successfully obtained using a salt elimination reaction between TiCl3(3THF) and [Li(i Prn BuAMD)] in a 65% yield, and the characterization of the compound was conducted using various characterization methods. The reported compound’s thermal performances were studied through thermal gravimetric analysis (TGA), and the result indicated that the reported titanium(III) amidinate compound exhibited a suitable volatility, high thermal stability, and sufficient vapor pressure. Furthermore, film material deposit was performed in a CVD reactor under low pressure, and a N/C-doped TiO2 film was successfully deposited.

Corrosion mechanisms of TiO2 photoelectrode coatings in alkaline conditions

The crystal structure of TiO2 has a significant impact on the chemical stability of the protective TiO2 thin films used in photoelectrochemical conditions. By altering the deposition temperature of atomic layer deposition method, and by post-deposition annealing treatments, amorphous, microcrystalline anatase, and Ti3+-rich nanocrystalline rutile structures can be achieved. In this paper, the chemical stability in alkaline solution and failure mechanisms of ALD grown TiO2 thin films on Si(100) were studied by SEM, XPS, EIS, and ellipsometry. The results showed that the electrically conductive Ti3+-rich nanocrystalline rutile thin film was chemically stable, whereas other samples failed within the first 10 h of the test in 1.0 M NaOH. More detailed analysis in 0.1 M NaOH revealed that the anatase sample experienced sudden failure after NaOH solution penetrated the TiO2 via grain boundaries, causing the Si substrate to dissolve. In contrast, the amorphous TiO2 films had more gradual failure as the NaOH solution permeated the TiO2 film, causing it to swell up to three times the initial thickness of the film.

Enhanced optical and electrical properties of PEO/PMMA/TiO2 nanocomposites for optoelectronic applications

In this study, we synthesized titanium oxide (TiO2) nanoparticles (NPs) via the sol-gel process and incorporated them into a polymer blend of polyethylene oxide (PEO) and polymethyl methacrylate (PMMA) to form PEO/PMMA/TiO2 nanocomposites. The TiO2 NPs were integrated into the polymer matrix using the casting method at varying concentrations (1, 2, and 3 wt.%). The structural, morphological, optical, and electrical properties of the prepared TiO2 and nanocomposite films were thoroughly characterized using techniques such as transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, and electrical impedance spectroscopy (EIS). TEM analysis revealed predominantly spherical TiO2 NPs with an average particle size of 15 nm. XRD and FTIR analyses confirmed the successful incorporation of TiO2 NPs and their interaction with the polymer chains, leading to modifications in the crystalline structure and chemical bonding of the nanocomposites. UV-Vis spectroscopy demonstrated a redshift in the absorption edge and increased absorbance with higher TiO₂ content, indicating enhanced optical properties. The indirect optical bandgap was observed to decrease from 4.19 eV to 2.21 eV as the TiO2 concentration increased, enhancing the material's photoresponsiveness. Additionally, the refractive index increased from 2.11 to 2.91, further supporting the potential for optical applications. EIS results showed a decrease in bulk resistance with increasing TiO2 concentration, suggesting improved electrical conductivity. These findings highlight the potential of PEO/PMMA/TiO2 nanocomposites for optoelectronic applications, where enhanced optical properties, such as improved light absorption, higher refractive index, and improved charge transport, are critical for device performance. The study offers an understanding of the PEO/PMMA/TiO2 nanocomposites, laying a foundation for future research in their applications in optoelectronic devices.

Crystallization and Optical Behaviour of Nanocomposite Sol-Gel TiO2:Ag Films.

Sol-gel spin coating method was employed for depositing TiO2 and Ag-doped TiO2 films. The effects of Ag doping and the annealing temperatures (300-600 °C) were studied with respect to their structural, morphological, vibrational, and optical properties. Field Emission Scanning Electron microscopy (FESEM) investigation exhibited the grained, compact structures of TiO2-based films. Ag incorporation resulted in a rougher film surface. X-ray diffraction (XRD) results confirmed the formation of Ag nanoparticles and AgO phase, along with anatase and rutile TiO2, strongly depending on Ag concentration and technological conditions. AgO fraction diminished after high temperature annealing above 500 °C. The vibrational properties were characterized by Fourier Transform Infrared (FTIR) spectroscopy. It was found that silver presence induced changes in IR bands of TiO2 films. UV-VIS spectroscopy revealed that the embedment of Ag NPs in titania matrix resulted in higher absorbance across the visible spectral range due to local surface plasmon resonance (LSPR). Ag doping reduced the optical band gap of sol-gel TiO2 films. The optical and plasmonic modifications of TiO2:Ag thin films by the number of layers and different technological conditions (thermal and UV treatment) are discussed.

Optical and stress properties of ZrO2/SiO2 and TiO2/SiO2 anti-reflective coatings deposited by ion-beam-assisted deposition on a flexible substrate

Dielectric films of ZrO2,TiO2, and SiO2 were deposited on flexible polycarbonate (PC) and polyethylene terephthalate (PET) substrates by using ion-beam-assisted deposition (IBAD). Each layer had a thickness ranging from 30 to 210 nm. The optical and anisotropic stress properties were investigated. Two anti-reflective coatings (ARCs), ZrO2/SiO2 and TiO2/SiO2, were selected and deposited on the PET flexible substrate. The anisotropic stresses of the single layer and ARCs were measured using a phase-shifting moiré interferometer. Experimental results showed that the optimal oxygen flow rates for the ZrO2,TiO2, and SiO2 films deposited with IBAD were 10, 10, and 15 sccm, respectively. The refractive index (n) was TiO2(2.37)>ZrO2(2.05)>SiO2(1.46), and the extinction coefficient (k) for all samples was below 10−3. The thermal expansion coefficient of the PC substrate was three times that of the PET substrate, and the high-refraction ZrO2 and TiO2 single-layer films presented cracks and distortions on the PC substrate. Only the low-refractive-index SiO2 sample did not present cracks. The three dielectric films did not crack or distort when deposited on the PET substrate. The anisotropic stress analysis provided the maximum principal and shear stresses for the three dielectric films on the PET substrate. Therefore, the maximum principal stress of the 210 nm single-layer film on a PET substrate is TiO2>ZrO2>SiO2. It was also discovered that the principal stress of the AR multilayer film is significantly decreased due to the damping stacking effect (DSE) of the high- and low-refractive-index materials, ZrO2/SiO2 ARC (−297.3MPa)>TiO2/SiO2ARC(−132.6MPa). Thus, the high packing density of TiO2 gives a better DSE than ZrO2.

Investigating the influence of RF power on the surface morphological and optical properties of sputtered TiO2 thin films

Thin films of titanium dioxide (TiO2), with thicknesses ranging from 105 to 231 nm, were deposited on glass substrates using radio-frequency (RF) magnetron sputtering in an argon atmosphere at four distinct RF power levels: 40, 70, 100, and 130 W, with the deposition time kept constant. The crystalline structure, surface morphology and optical and semiconductor properties of the obtained films were analyzed using X-ray diffraction (XRD), Atomic Force Microscopy (AFM) and UV–visible transmittance spectroscopy. These analyses revealed that the crystallinity of the films improves with increasing RF power, corresponding to an increase in film thickness. Consequently, the samples transition from poorly crystalline or amorphous structure to a monocrystalline rutile phase with a (110) texture. However, at the highest RF power studied, this texture is partially disrupted by the formation of nanocrystals with different orientations. The surface roughness exhibited multifractal characteristics, with complexity systematically decreasing and surface stiffness reducing as RF power increased. Refractive indices and optical band gap energies were determined using the Swanepoel and Tauc plot methods, respectively. The films exhibited a notable increase in the refractive index and a decrease in the optical band gap, from 3.81 eV to 3.52 eV, as the RF power was increased. This underscores the influence of RF power on the optical and semiconductor properties of TiO2 films.

Visible color camouflage and infrared, laser band stealth, compatible with dual-band radiative heat dissipation

Infrared stealth technology garners significant attention due to its value in military applications. With the rise of multi-band detection technologies, the infrared stealth target is easily detected. Therefore, it is urgent to study multi-band camouflage devices. Here, this paper proposes a multi-band camouflage device composed of ZnS, Ge, TiO2, crystalline Ge2Sb2Te5 (cGST) and Ag multilayer films, which can realize multi-band camouflage across visible, mid-wave infrared (MWIR, ε3∼5 μm = 0.22), long-wave infrared (LWIR, ε8∼14 μm = 0.16), and laser (R1.06 μm = 0.01) spectra. In addition, effective radiative heat dissipation was realized in two non-atmospheric transparent windows (ε2.5–3 μm = 0.51 and ε5∼8 μm = 0.65). Among them, visible camouflage in different background environments can be realized independently by adjusting the thickness of the ZnS film to produce different structural colors. Notably, this emissivity spectrum remains robust even as the incident angle increases to 60°. These results can guarantee the realization of multi-band infrared camouflage, laser camouflage and radiation heat dissipation. This study not only addresses high-efficiency infrared camouflage and thermal management but also achieves outstanding visible and laser camouflage performance, offering a comprehensive guidance for advancing multi-band camouflage technology.

FT-IR detection of DMMP on TiO2-Modified porous silicon substrates

In this study, we present a new chemical sensor based on a functionalized porous silicon and sensitive to dimethyl methyl phosphonate (DMMP), a simulant of sarin gas, known as one of the most toxic warfare agents. The porous silicon was prepared by anodising a boron-doped p-Si (100) wafer. A metal oxide TiO2 layer was then deposited by thermal evaporation of Ti and oxidized under atmospheric conditions to form a TiO2 film which was used as a reactive coating. The characterization of the PSi and TiO2/PSi films was investigated using SEM, EDX and XPS spectroscopies. The results indicated that the TiO2 was well incorporated on the surface and slightly inside the porous silicon layer. FT-IR studies were then carried out before and after exposure to DMMP and the detection performance was compared with PSi. The results obtained showed that our surfaces have the ability to detect DMMP down to 0.5 ppm compared to uncoated PSi layer. We have also shown that a TFA pre-treatment of our TiO2 modified PSi, prior the exposure to DMMP, is crucial for increasing its sensitivity and that our sensor can be reused several times with a simple hexane cleaning step, a key criterion for routine applications.

One-Step Magneton Sputtering of Crystalline Cu-Doped TiO2 Coatings: Characterization and Antibacterial Activity

Early biofilm formation could be inhibited by applying a thin biocompatible copper coating to reduce periprosthetic infections. In this study, we deposited crystalline Cu-doped TiO2 films using one-step DC magnetron sputtering in an oxygen atmosphere on a biased Ti6Al4V alloy without external heating. The bias voltage varied from −25 V to −100 V, and the resultant substrate temperature was measured. The deposited coatings were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), microhardness, scratch and hydrophilicity tests, potentiodynamic polarization measurements, and antibacterial assays against S. aureus and E. coli. The findings demonstrated that when a higher negative bias is applied, the substrate temperature drops, and the anatase to rutile transformation is initiated without indicating obvious Cu-containing phases. The SEM images of the films showed spherical agglomerates with homogeneously distributed Cu with decreasing Cu content as the bias value increased. Higher bias results in the grain refinement of the thinning coatings with more lattice microstrain and more defects, together with an increase in water contact angles and hardness values. Samples biased at −75 V exhibited the highest adhesive strength between coatings and substrate, whereas the specimen biased at −50 V demonstrated higher corrosion resistance. Cu-containing TiO2 coatings with pure anatase phase composition and Cu concentrations of 2.62 wt.% demonstrated excellent bactericidal activity against both S. aureus and E. coli. The layers containing 2.34 wt.% Cu exhibited very good antibacterial properties against S. aureus, only. According to these findings, the produced copper-doped TiO2 coatings have high bactericidal qualities in vitro and may be used to prepare orthopaedic and dental implants in the future.

Impact of plasma power on plasma enhanced atomic layer deposited TiO2 as a spacer

As the size of devices is scaled down, micro-patterning technology is increasing in importance. In micro-patterning, spacers require precise thickness and uniform deposition at low temperature. To meet these requirements, atomic layer deposition (ALD), which can be controlled to an accurate thickness, was introduced. Therefore, we investigated plasma-enhanced ALD using radicals for high reactivity. Optical emission spectroscopy and a Langmuir probe were used to evaluate plasma properties such as radical intensity and plasma density at different plasma powers. Regardless of plasma power, growth per cycle and compositions of Ti and O remained constant. X-ray photoelectron spectroscopy showed that application of 500 W decreased the area of Ti2O3 from 20.2 % to 4.5 % compared with 100 W due to the increased amount of oxygen radicals. X-ray reflectivity results showed a 4.09 g/cm3 density of TiO2 film at 100 W, which increased to 4.2 g/cm3 at 500 W, indicating a decrease of Ti2O3. Meanwhile, the wet etch rate of TiO2 film was 1.72 Å/min at 100 W and 0.8 Å/min at 500 W, and the denser film had superior etch resistance. Finally, transmission electron microscopy showed that step coverage of TiO2 films improved from 90.9 % to 99.9 % with increasing power. Thus, application of high power effectively improved the properties of TiO2 films.

Tin-doped titanium dioxide film-enhanced electrocatalytic hydrogen evolution

Electrocatalyst water-splitting based on metal oxide nanocomposites has gained considerable interest in hydrogen evolution applications. Here, undoped titanium dioxide and tin-doped titanium dioxide films (TiO2 and Sn/TiO2, respectively) are presented for highly efficient H2 production applications. The crystal structure analysis is performed by analyzing the XRD patterns using the Rietveld refinement method and the Williamson-Hall method. XRF scans are used to confirm the doping mechanism between Sn and TiO2. The bandgap energies of undoped TiO2 and Sn/TiO2 films are 3.33 and 3.15 eV, respectively. On the other hand, the electrical conductivity values of undoped TiO2 and Sn/TiO2 films are 0.10 and 0.25 mS.cm−1, respectively. The electrochemical H2 production performance of undoped TiO2 and Sn/TiO2 films is investigated through two different methods: potentiostat measurements and analytical methods. It can be concluded that the Sn/TiO2 film exhibits higher HER performance and H2 production efficiency than the undoped TiO2 film.

Optimizing deposition parameters and characterizing TiO2 thin films for future memristor applications

Titanium dioxide (TiO2) thin films were deposited on glass substrates using Spray Pyrolysis technique, with variations in multiple deposition parameters. The molarity of the precursor was altered within a small range from 0.09 M–0.15 M. The deposition temperature was systematically adjusted from 200 °C to 400 °C while the ratio between precursor and chelating agent varied between 1:1,1:2 and 1:3. The thickness of TiO2 films were found to be in the range of 216 nm to 14.9 μm. Structural analysis conducted by XRD confirmed the formation of anatase TiO2 thin films. Optical studies using UV-Visible spectrophotometer determined the absorption and indirect bandgap ranging from 299 nm to 326 nm and 3.08 eV to 3.44 eV respectively. Electrical studies carried out evaluated the leakage currents and DC resistivity for all individual films with the input voltage applied from ± 0.5 V to ± 5V. Impedance studies were conducted by varying input voltages from 0.2V–3V for each film, so as to examine the resultant impedance, dielectric constant, dielectric loss, conductivity, admittance and modulus spectra. The obtained results were analysed to optimise the deposition parameters for designing future memristors with specific individual or combined characteristics, such as high ON/OFF, switching speed, endurance and retention.

Evaluation of corrosion properties of TA2-Q345 explosive composite plate at different heat treatment temperatures

This study investigated the effects of post-weld heat treatment (PWHT) at 500 °C, 600 °C, 700 °C, and 800 °C on the microstructure and corrosion performance of the TA2-Q345 explosive composite plate, with TA2 as the flyer plate and Q345 as the base plate. X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses were performed, alongside electrochemical experiments. The explosive welding interface of the TA2-Q345 composite plate exhibited a characteristic wavy structure, which indicated high welding quality. The XRD results indicated that the PWHT temperature significantly affects both the phase structure and the intensity of the diffraction peaks of the oxide film. Additionally, the porosity calculations demonstrated that the sample subjected to PWHT at 500 °C exhibited the lowest porosity in the surface oxide film, resulting in a denser oxide film that effectively enhanced corrosion resistance. However, as the temperature continued to rise, defects such as craters, bulges, and delamination between the oxide film and the titanium matrix were observed. The results of the electrochemical analysis indicated that, compared to untreated samples, the PWHT samples demonstrated improved corrosion resistance. Specifically, the sample with PWHT at 500 °C has the lowest corrosion current density (icorr) of 6.1892E-06 A/cm2, while the untreated sample has the highest icorr of 6.3577E-05 A/cm2, indicating that 500 °C is the optimal temperature. The corrosion process involved the hydrolysis of titanium chloride to form a TiO2 film and localized corrosion of the TiO2 protective film. The corrosion products composed of mainly C, O, and Ti were dispersed on the surface of PWHT samples.

TiO2 Films with Macroscopic Chiral Nematic-Like Structure Stabilized by Copper Promoting Light-Harvesting Capability for Hydrogen Generation.

Cellulose nanocrystals (CNCs) have inspired the synthesis of various advanced nanomaterials, opening opportunities for different applications. However, a simple and robust approach for transferring the long-range chiral nematic nanostructures into TiO2 photocatalyst is still fancy. Herein, a successful fabrication of freestanding TiO2 films maintaining their macroscopic chiral nematic structures after removing the CNCs biotemplate is reported. It is demonstrated that including copper acetate in the sol avoids the epitaxial growth of the lamellar-like structure of TiO2 and stabilizes the chiral nematic structure instead. The experimental results and optical simulation demonstrate an enhancement at the blue and red edges of the Fabry-Pérot reflectance peak located in the visible range. This enhancement arises from the light scattering effect induced by the formation of the chiral nematic structure. The nanostructured films showed 5.3 times higher performance in the photocatalytic hydrogen generation, compared to lamellar TiO2, and benefited from the presence of copper species for charge carriers' separation. This work is therefore anticipated to provide a simple approach for the design of chiral nematic photocatalysts and also offers insights into the electron transfer mechanisms on TiO2/CuxO with variable oxidation states for photocatalytic hydrogen generation.

Structural, Morphological, and Optical Properties of TiO2/CdS Core-Shell System Prepared by Two Method for Photoelectrocatalytic Application

Abstract The present study utilized the hydrothermal technique to carry out the deposition of films of TiO2. The deposition of CdS on the TiO2 films was accomplished using the chemical bath deposition (CBD) and successive ionic layer adsorption and reaction (SILAR) methods. The morphological and structural characteristics of the TiO2/CdS thin films were investigated using a combination of XRD, SEM, EDX, and AFM techniques. Additionally, the optical properties of the nanostructures were examined using UV-Visible and PL spectroscopic techniques. The X-Ray Diffraction pattern of all TiO2 films revealed the formation of the anatase phase. The CdS present in the Ti/TiO2/CdS samples exhibited a hexagonal structure. The hydrothermal technique employed in the preparation of the TiO2 thin films resulted in the formation of nanofiber morphology, which was evident from the SEM images. The absorption edge data for the TiO2/CdS films demonstrated a shift towards the visible region, indicating a decrease in the bandgap as compared to the TiO2 nanostructure. Significantly improved photoelectrocatalytic performance was observed in the Ti/TiO2/CdS samples prepared using the CBD method, surpassing that of the Ti/TiO2/CdS samples prepared using the SILAR method.

Study on electro-optical dual-control color-changing and energy-storage device based on Mo-WO3 and Al-TiO2 thin film electrode

Under optical and electrical control, a multifunctional electro-optical dual-control color-changing and energy-storage device not only realizes quick color conversion, but also achieves good storage performance. In this work, Mo doped WO3 (Mo-WO3) films were synthesized through one-step hydrothermal method and N719/Al doped TiO2 (N719/Al-TiO2) films were synthesized by hydrothermal and dip-dyeing method. Eventually, choosing Mo-WO3 as cathode and N719/Al-TiO2 film as anode, a multifunctional electro-optical dual-control Mo-WO3@N719/Al-TiO2 color-changing and energy-storage device was constructed. Under electrical control, the device shows excellent coloration efficiency (73.99 cm2/C), fast color switching rate (coloring/ bleaching time is 3.6 s/1.4 s), obviously improved area capacitance (about 82.6 mF/cm2) and excellent cycle stability. Under optical control, the device also shows shortened response time (coloring/ bleaching is 64.3 s/143.4 s), outstanding coloration efficiency (70.49 cm2/C), better area capacitance (about 58.6 mF/cm2) and excellent photoelectric conversion efficiency (10.56 %).

Microstructure and dry sliding wear evaluation of functionally graded coating deposited via atmospheric plasma spray

Surfaces are commonly enhanced with wear-resistant coatings to improve their resistance to abrasion, erosion, and other forms of wear. These coatings play a crucial role in extending the lifespan and improving the performance of materials and components exposed to challenging conditions. The objective of the current study is to deposit thermally sprayed 3-layer TiC–12Co–10ZrO2/NiCoCrAlMo functionally graded coatings on SS410 substrates using atmospheric plasma spray. The results revealed that by employing appropriate ceramic proportions, the microhardness of graded coatings increased to 990.4 HV, which is approximately 3.21 times higher than that of the substrate. Furthermore, the tribological properties of graded coating exhibited superior resistance compared to the substrate, where process settings were varied. Specifically, graded coating samples subjected to the applied load, sliding distance, and sliding velocity showed improved wear resistance of 78.51%, 68.42%, and 76.66% respectively in extreme conditions compared with uncoated samples. The characterization of the worn surface revealed a sequential occurrence of wear mechanisms: abrasive, adhesive, and delamination. The formation of TiO2 and Cr2O3 tribo-oxide film protects the surface against the wear mechanism and is applicable in extreme wear environments.

Photo-electrochemical study of TiO2/Co3O4 thin films in polluted electrolyte: A promising route for coupling hydrogen production with water remediation

The use of a photo-electrochemical cell (PEC) to produce hydrogen from wastewater is a promising innovation. In this context, this study investigates the impact of a pollutant on the photo-electrochemical properties of sol-gel synthesized TiO2 and TiO2–Co3O4 thin films for hydrogen production in a polluted electrolyte. Combining the photocatalytic properties of TiO2 with the electronic properties of Co3O4 offers an effective solution for achieving effective photo-electrochemical properties in polluted environments. Nevertheless, despite the lowest photocatalytic activity, the hybrid thin film TiO2–Co3O4 with the highest Ti/Co ratio (1:0.5) shows the most promising performance with simultaneous 11.4 μmol cm−2 h−1 H2 production and 12% acid orange 7 degradation after 3 h irradiation under xenon light without the use of any sacrificial agent. This indicates that the electronic conductivity provided by the presence of Co3O4 is a critical property for achieving optimal performance in PEC coupling for hydrogen production and wastewater treatment.