Recombination Of Electron-hole Pairs Research Articles

Investigation of the efficacy of Zn/Ce-CuO nanoparticles for enhanced photocatalytic, antibacterial, and antioxidant activities.

The world is dealing with unprecedented environmental challenges, leading to a growing urgency to limit environmental damage. So, this study focuses on the synthesis of pure CuO, Zn, Ce, and Zn/Ce dual-doped CuO nanoparticles (NPs)using extract of Citrus limon leaves as reductant via simple co-precipitation method. The X-ray diffraction (XRD) characterization was employed to analyze structural characteristics of synthesized samples which confirm influence of Zn or Ce doping on crystallite size, dislocation density, and strain. The role of functional groups, changes in force constant, and bond length on addition of dopants was indicated by FTIR results. The SEM and TEM results showed variation in morphology from irregular to spherical. The zeta-potential and BET analysis confirmed surface potential as well as surface area characteristics. The change in energy gap values from 1.81 to 1.45eV of Zn/Ce-doped CuO NPscomputed from UV-vis analysis elevated its photocatalytic performance and reduced the chances of recombination of electron-hole pair due to presence of trapping levels between valence and conduction bands. The enhanced photo-degradation of Congo red (CR) and rhodamine B (RhB) with 91 and 94%, respectively, for Zn/Ce-doped CuO NPswas observed. The so-obtained samples have also exhibited good antibacterial and antioxidant activities.

An efficient NiS-ReS2/CdS nanoparticles with dual cocatalysts for photocatalytic hydrogen production

The construction of heterojunctions is one of efficacious ways to improve the charge transfer and suppress the recombination of photoexcited electron-hole pairs for enhancing reactive activities of photocatalysts. Ternary NiS-ReS2/CdS composites are synthesized via a one-step hydrothermal method and the heterojunction nanostructures are achieved. The NiS-ReS2/CdS photocatalyst exhibits the superior photocatalytic activity with a hydrogen production rate up to 139 mmol g−1 h−1, which is much higher than binary composites and pure CdS. The contributions of the dual cocatalysts NiS and ReS2 are verified to narrower bandgaps, lower resistances and increase photocurrent density of NiS-ReS2/CdS, promoting the absorption of visible light and the migration of photoinduced electrons. The NiS-ReS2/CdS heterostructures provide a possible dual Z-scheme path for the rapid transfer of electrons. The tailoring of the dual cocatalysts is effective to improve the photocatalytic hydrogen production.

A Dual-Active Covalent Triazine Framework Film for Efficient Visible-Light-Driven Hydrogen Peroxide Production.

Photocatalytic hydrogen peroxide production from water and oxygen offers a clean and sustainable alternative to the conventional energy-intensive anthraquinone oxidation method. Compared to powdered covalent triazine frameworks (CTFs), the film morphology of CTFs provides better connectivity in 2D, yielding several advantages: more efficient connections between active sites, reduced electron-hole pair recombination, increased resistance to superoxide radical induced corrosion, and decreased light scattering. Leveraging these benefits, it has incorporated dual active sites for both the oxygen reduction reaction (ORR) and the water oxidation reaction (WOR) into a CTF film system. This dual-active CTF film demonstrated an exceptional hydrogen peroxide production rate of 19460µmolh⁻¹m⁻2 after 1h and 17830µmolh⁻¹m⁻2 after 5h under visible light irradiation (≥420nm) without the need for sacrificial agents.

Eu-doped ZnO coatings prepared by spray pyrolysis for photocatalytic applications

The ZnO-Eu2O3 coatings immobilized on stainless steel foil were synthesized by a spray pyrolysis method using an inorganic salt, Zn(CH3COO)2·2H2O, and Eu2O3 nanopowder with different Zn/Eu ratios. The coatings were investigated by SEM, XRD, XPS, DRS, and photoluminescence analysis, and their photoactivity was studied in the degradation of two pollutants, lindane and methyl orange. The ZnO-Eu2O3 coatings were more photoactive than coatings containing only ZnO. Among the ZnO-Eu2O3 coatings, the photocatalyst with 2 wt% Eu2O3 showed the highest photoactivity for both pollutants. The incorporation of Eu+3 ions into the ZnO crystal lattice causes the appearance of oxygen vacancy defects and better charge separation in the ZnO-Eu2O3 coating. When the Eu2O3 concentration exceeds 2 wt%, the photoactivity decreases as additional centers for electron-hole pair recombination are created. It is shown that the main factor influencing the photoactivity of Eu-doped ZnO composite coatings is the amount of Eu3+ incorporated into the ZnO lattice.

Eu-doped ZnO coatings prepared by spray pyrolysis for photocatalytic applications

The ZnO-Eu2O3 coatings immobilized on stainless steel foil were synthesized by a spray pyrolysis method using an inorganic salt, Zn(CH3COO)2·2H2O, and Eu2O3 nanopowder with different Zn/Eu ratios. The coatings were investigated by SEM, XRD, XPS, DRS, and photoluminescence analysis, and their photoactivity was studied in the degradation of two pollutants, lindane and methyl orange. The ZnO-Eu2O3 coatings were more photoactive than coatings containing only ZnO. Among the ZnO-Eu2O3 coatings, the photocatalyst with 2 wt% Eu2O3 showed the highest photoactivity for both pollutants. The incorporation of Eu+3 ions into the ZnO crystal lattice causes the appearance of oxygen vacancy defects and better charge separation in the ZnO-Eu2O3 coating. When the Eu2O3 concentration exceeds 2 wt%, the photoactivity decreases as additional centers for electron-hole pair recombination are created. It is shown that the main factor influencing the photoactivity of Eu-doped ZnO composite coatings is the amount of Eu3+ incorporated into the ZnO lattice.

Eu-doped ZnO coatings prepared by spray pyrolysis for photocatalytic applications

The ZnO-Eu2O3 coatings immobilized on stainless steel foil were synthesized by a spray pyrolysis method using an inorganic salt, Zn(CH3COO)2·2H2O, and Eu2O3 nanopowder with different Zn/Eu ratios. The coatings were investigated by SEM, XRD, XPS, DRS, and photoluminescence analysis, and their photoactivity was studied in the degradation of two pollutants, lindane and methyl orange. The ZnO-Eu2O3 coatings were more photoactive than coatings containing only ZnO. Among the ZnO-Eu2O3 coatings, the photocatalyst with 2 wt% Eu2O3 showed the highest photoactivity for both pollutants. The incorporation of Eu+3 ions into the ZnO crystal lattice causes the appearance of oxygen vacancy defects and better charge separation in the ZnO-Eu2O3 coating. When the Eu2O3 concentration exceeds 2 wt%, the photoactivity decreases as additional centers for electron-hole pair recombination are created. It is shown that the main factor influencing the photoactivity of Eu-doped ZnO composite coatings is the amount of Eu3+ incorporated into the ZnO lattice.

Amplifying Photochromic Response in Tungsten Oxide Films with Titanium Oxide and Polyvinylpyrrolidone.

Tungsten oxide (WO3) is known for its photochromic properties, making it useful for smart windows, displays, and sensors. However, its small bandgap leads to rapid recombination of electron-hole pairs, resulting in poor photochromic performance. This study aims to enhance the photochromic properties of WO3 by synthesizing hexagonal tungsten oxide via hydrothermal synthesis, which increases surface area and internal hydrates. Titanium oxide (TiO2) was adsorbed onto the tungsten oxide to inject additional charges and reduce electron-hole recombination. Additionally, polyvinylpyrrolidone (PVP) was used to improve dispersion in organic solvents, allowing for the fabrication of high-quality films using the doctor blade method. Characterization confirmed the enhanced surface area, crystal structure, and dispersion stability. Reflectance and transmittance measurements demonstrated significant improvements in photochromic properties due to the composite structure. These findings suggest that the introduction of TiO2 and PVP to tungsten oxide effectively enhances its photochromic performance, broadening its applicability in various advanced photochromic applications.

Synthesis and characterization of Cu and Tb substituted NiFe2O4@MXene nanocomposite as a new photocatalyst for removal of organic dyes and drugs from industrial wastewater

The study aimed to establish a correlation between the photocatalytic degradation of Congo red (CR), Crystal violet (CV) dyes and Diclofenac sodium (DS) drug by copper, terbium substituted nickel ferrite (CuxNi1-xTbyFe2-yO4) and MXene (CTNF/MXene) composite where (x, y = 0.1). Terbium and copper doping reduced crystallite size, band gap energy, improve visible light absorption and impede electron-hole pair recombination. Superior complexation ability of terbium forces more pollutants to adsorb on the surface of photocatalyst and hence more degradation. Results indicated that MXene, acting as a co-catalyst, effectively lowered the charge recombination rates by electron trapping and enhanced the visible light absorption, improving the photocatalytic activity. CTNF/MXene composite exhibited greater rate constant and photocatalytic degradation of CR (91 %), CV (77 %) and DS (81 %) as compared to NF, CNF, TNF, CTNF. The increased surface area of CuxNi1-xTbyFe2-yO4 with MXene and reduced electron-hole pair recombination are possible factors for its successful use as photocatalyst.

Photocatalytic activities of the ZnO:CuO nanocomposites synthesized by microwave-assisted hydrothermal under UV-Vis irradiation

The ZnO:CuO nanocomposite photocatalytic activity was experimentally and numerically investigated. This nanocomposite exhibits stability and durability during photodegradation. The nanocomposite with a ZnO/CuO ratio of 2.0 synthesized by microwave-assisted hydrothermal at 70 °C in 10 minutes exhibits a photocurrent density of over 1.0 mA.cm−2 for the ZnO layer and an optimal degradation efficiency of 86.4 %. The photocatalytic efficacy of the ZnO:CuO nanocomposite depends on the current generated by ZnO rather than the total density of photo-induced current. This nanocomposite can be a promising photocatalyst because of its enhanced light absorption and effective suppression of photogenerated electron-hole pair recombination.

Biomass-derived activated carbon nanocomposites with multicolor photoluminescence

In this research work, synthesis, structural, and optical properties of activated carbon (AC) and AC/metal oxide nanocomposites (AC/ZnO and AC/Fe3O4) have been studied. Uniformly distributed metal oxide in AC (AC/ZnO and AC/Fe3O4) nanocomposites were obtained by a single-step impregnation-carbonization method, using bamboo as the biomass precursor, ZnCl2, and FeCl3 as chemical activating agents. The microstructural evolutions and optical characteristics of AC, and the composites have been investigated using X-ray diffraction (XRD), Raman, X-ray photoelectron spectroscopy (XPS), and photoluminescence spectroscopy. Both AC and composites exhibited broad photoluminescence (PL) emissions in the visible region. The PL emissions at 462 and 603 nm by AC were due to the radiative recombination of electron-hole pairs generated by sp2 sites embedded in the sp3 matrix. However, two new emission centers in addition to the above appeared at 520 and 560 nm, in both AC/ZnO and AC/Fe3O4 nanocomposites. The study suggests that metal oxide formation in composites led to a new sp2 cluster formation with a new energy band resulting in two additional emission centers in the green light region. This work provides a simple, cost-effective, and efficient way to develop broadband luminescent materials in visible regions with potential optical and sensing applications.

Construction of g-C3N4/Ti3CN MXene Schottky heterojunctions for boosting photocatalytic hydrogen production

Converting solar energy into clean hydrogen (H2) fuel via photocatalytic hydrogen production technology is a promising strategy for sustainable social development. Graphitic carbon nitride (g-C3N4) has attracted much attention due to its unique visible light activity and excellent tunable atomic structure. However, bulk g-C3N4 suffers from challenges such as sluggish charge carrier dynamics and limited active catalytic sites, resulting in lower solar-to-hydrogen conversion efficiency. Herein, we prepare defective ultrathin g-C3N4 nanosheets and subsequently construct 2D g-C3N4/2D Ti3CN MXene heterojunction via electrostatic-driven assembly. The optimized composite CM-2 exhibits the highest hydrogen evolution rate of 7630.5 μmol g−1 h−1. The increase in the hydrogen production rate is attributed to the effective coupling of two materials to form Schottky heterojunctions, which may inhibit the recombination of electron-hole pairs. Additionally, this work explores the pathway of electron transfer in Schottky photocatalyst, and further unveils the synergy of defects and built-in electric field in accelerating photo-induced charge transport as well as enhancing the hydrogen-evolving activity, thereby providing valuable insights for the rational design of highly efficient photocatalytic materials.

Fabrication of Flower-Shaped Sb2S3/Fe2O3 Heterostructures for Enhanced Photoelectrochemical Performance.

Antimony sulfide (Sb2S3) has been recognized as a catalytic material for splitting water by solar energy because of its suitable narrow band gap, high absorption coefficient, and abundance of elements. However, many deep-level defects in Sb2S3 result in a significant recombination of photoexcited electron-hole pairs, weakening its photoelectrochemical performance. Here, by using a simple hydrothermal and spin-coating method, we fabricated a step-scheme heterojunction of Sb2S3/α-Fe2O3 to improve the photoelectrochemical performance of pure Sb2S3. Our Sb2S3/α-Fe2O3 photoanode has a photocurrent density of 1.18 mA/cm2 at 1.23 V vs reversible hydrogen electrode, 1.39 times higher than that of Sb2S3 (0.84 mA/cm2). In addition, our heterojunction has a lower onset potential, a higher absorbance intensity, a higher incident photon-to-current conversion efficiency, a higher applied bias photon-to-current efficiency, and a lower charge transfer resistance compared to pure Sb2S3. Based on ultraviolet photoelectron spectroscopy, we constructed a step-scheme band structure of Sb2S3/α-Fe2O3 to explain its photoelectrochemical enhancement. This work offers a promising strategy to optimize the performance of Sb2S3 photoelectrodes for solar-driven photoelectrochemical water splitting.

Mg doped zinc manganese spinel ferrite: Fabrication and investigation of the structural and photocatalytic properties

To deal with environmental issues and wastewater treatments, the development and synthesis of highly effective semiconducting photocatalysts is a promising route. Sol-gel route was used for the preparation of zinc manganese ferrite (Zn0.6Mn0.4Fe2O4) and magnesium doped zinc manganese ferrite ((Zn0.6Mn0.4Mg0.06Fe2O4). However, the ultrasonication method was utilized for the fabrication of magnesium doped zinc manganese ferrite@CNTs nanocomposite (Zn0.6Mn0.4Mg0.06Fe2O4@CNTs). Characterization of materials was done via different techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Electrochemical impedance spectroscopy (EIS), UV–vis spectroscopy, and Mott-Schottky analysis. The crystallite size was calculated using the Debye-Scherrer formula. With the addition of magnesium in the zinc manganese ferrite, the band gap declines from 2.51 eV to 2.21 eV. The photocatalysis was carried out against the methyl orange (MO) and colorless effluent benzoic acid. By Zn0.6Mn0.4Mg0.06Fe2O4@CNTs, the % removal of MO was 92.22 % whereas for BO it was 34 %. Charge transfer resistance and flat band potential values for the nanocomposite were 1.12 Ω and 0.33 V respectively. The incorporation of CNTs into Zn0.6Mn0.4Mg0.06Fe2O4 accelerated the efficiency of photocatalysts, enhanced the migration of electrons, and suppressed the electron-hole pair recombination. Due to more surface area, the Zn0.6Mn0.4Mg0.06Fe2O4@CNTs showed the utmost results and acted as a highly proficient photocatalyst for the removal of organic effluents.

Enhanced photocatalytic hydrogen evolution performance of Pd/g-C3N4 with carbon vacancies

Exploration of highly active, stable and environmentally friendly photocatalytic materials is key to address the problem for hydrogen production by photocatalytic water splitting. Among all the photocatalysts, graphitic carbon nitride (g-C3N4) has gained attention for its stable graphite-like electronic structure, appropriate band gap (∼2.7 eV), and high stability. However, the limited visible light absorption capacity and fast recombination of electron-hole pairs severely limit the photocatalytic performance of g-C3N4. In this study, Pd/g-C3N4 Schottky heterojunctions with carbon vacancies were prepared by an impregnation method. The surface plasmon resonance (SPR) effect of Pd0 nanoparticles and the incorporation of carbon vacancies synergistically reduce the band gap of g-C3N4, expanding its light response absorption capacity and increasing surface active sites, as a result of these modifications, the separation of electron-hole pairs is effectively improved, and photocatalytic water splitting for hydrogen production is greatly enhanced. Photocatalytic performance of Pd/g-C3N4 photocatalysts demonstrate outstanding hydrogen evolution efficiency under solar light irradiation. A convincing mechanism for the enhanced photocatalytic performance of the Pd/g-C3N4 Schottky heterojunctions was suggested. This investigation emphasizes a straightforward and efficient approach for fabricating of based g-C3N4 composite materials with exceptional photocatalytic efficiency.

Accumulation of Long-Lived Photogenerated Holes at Indium Single-Atom Catalysts via Two Coordinate Nitrogen Vacancy Defect Engineering for Enhanced Photocatalytic Oxidation.

Visible-light-driven photocatalytic oxidation by photogenerated holes has immense potential for environmental remediation applications. While the electron-mediated photoreduction reactions are often at the spotlight, active holes possess a remarkable oxidation capacity that can degrade recalcitrant organic pollutants, resulting in nontoxic byproducts. However, the random charge transfer and rapid recombination of electron-hole pairs hinder the accumulation of long-lived holes at the reaction center. Herein, a novel method employing defect-engineered indium (In) single-atom photocatalysts with nitrogen vacancy (Nv) defects, dispersed in carbon nitride foam (In-Nv-CNF), is reported to overcome these challenges and make further advances in photocatalysis. This Nv defect-engineered strategy produces a remarkable extension in the lifetime and an increase in the concentration of photogenerated holes in In-Nv-CNF. Consequently, the optimized In-Nv-CNF demonstrates a remarkable 50-fold increase in photo-oxidative degradation rate compared to pristine CN, effectively breaking down two widely used antibiotics (tetracycline and ciprofloxacin) under visible light. The contaminated water treated by In-Nv-CNF is completely nontoxic based on the growth of Escherichia coli. Structural-performance correlations between defect engineering and long-lived hole accumulation in In-Nv-CNF are established and validated through experimental and theoretical agreement. This work has the potential to elevate the efficiency of overall photocatalytic reactions from a hole-centric standpoint.

Graphene Quantum Dots as Hole Extraction and Transfer Layer Empowering Solar Water Splitting of Catalyst-Coupled Zinc Ferrite Nanorods.

Despite the narrow band gap energy, the performance of zinc ferrite (ZnFe2O4) as a photoharvester for solar-driven water splitting is significantly hindered due to its sluggish charge transfer and severe charge recombination. This work reports the fabrication of a hybrid nanostructured hydrogenated ZnFe2O4 (ZFO) photoanode with enhanced photoelectrochemical water-oxidation activity through coupling N-doped graphene quantum dots (GQDs) as a hole transfer layer and Co-Pi as a catalyst. The GQDs not only reduce the surface-mediated nonradiative electron-hole pair recombination but also induce a built-in interfacial electric field leading to a favorable band alignment at the ZFO/GQDs interface, helping rapid photogenerated hole separation and serving as a conducting hole transfer highway, improve the hole transportation into the Co-Pi catalyst for enhanced water oxidation reaction kinetics. The optimized ZFO/GQD/Co-Pi hybrid photoanode delivers a 23-fold photocurrent enhancement at 1.23 V versus the reversible hydrogen electrode (RHE) and a significant 360 mV reduction in the onset potential, reaching 0.65 VRHE compared with the ZFO photoanode under 1 sun illumination in a neutral electrolytic environment. This investigation underscores the mechanism of synergistic interplay between the hole transport layer and cocatalyst in boosting the solar-illuminated water-splitting activity of the ZFO photoanode.

Enhanced optical and electrochemical properties of FeBTC MOF modified TiO2 photoanode for DSSCs application

In this work, iron based 1, 3, 5-tricarboxylic acid (FeBTC) was prepared via microwave-assisted method and incorporated into TiO2 via ultrasonic assisted method. The TiO2–FeBTC nanocomposites were characterized by XRD, FTIR, Raman, BET, FESEM, HRTEM, TGA, UV‒vis DRS and PL to understand their crystallographic, surface morphology, and optical characteristics. The Raman spectra showed a blue shift of Eg, A1g, and B1g peaks upon incorporation of FeBTC MOF onto TiO2. HRTEM and XRD analysis confirmed a mixture of TiO2 nanospheres and hexagonal FeBTC MOF morphologies with high crystallinity. The incorporation of FeBTC onto TiO2 improved the surface area as confirmed by BET results, which resulted in improved absorption in the visible region as a results of reduced bandgap energy from 3.2 to 2.84 eV. The PL results showed a reduced intensity for TiO2–FeBTC (6%) sample, indicating improved separation of electron hole pairs and reduced recombination rate. After fabrication of the TiO2–FeBTC MOF photoanode, the charge transfer kinetics were enhanced at TiO2–FeBTC MOF (6%) with Rp value of 966 Ω, as given by EIS studies. This led to high performance due to low charge resistance. Hence, high power conversion efficiency (PCE) value of 0.538% for TiO2–FeBTC (6%) was achieved, in comparison with other loadings. This was attributed to a relatively high surface area which allowed more charge shuttling and thus better electrical response. Conversely, upon increasing the FeBTC MOF loading to 8%, significant reduction in efficiency (0.478%) was obtained, which was attributed to sluggish charge transfer and fast electron–hole pair recombination rate. The TiO2–FeBTC (6%) may be a good candidate for use in DSSCs as a photoanode materials for improved efficiency.

BiVO4-based heterojunction nanophotocatalysts for water splitting and organic pollutant degradation: a comprehensive review of photocatalytic innovation

Abstract The novel semiconductor photocatalytic material bismuth vanadate (BiVO4) is gaining significant attention in research due to its unique characteristics, which include a low band gap, good responsiveness to visible light, and non-toxic nature. However, intrinsic constraints such as poor photogenerated charge transfer, slow water oxidation kinetics, and fast electron–hole pair recombination limit the photocatalytic activity of BiVO4. Building heterojunctions has shown to be an effective strategy for enhancing charge separation and impeding electron–hole pair recombination over the last few decades. This review covers the state-of-the-art developments in heterojunction nanomaterials based on BiVO4 for photocatalysis. It explores heterojunction design, clarifies reaction mechanisms, and highlights the current developments in applications including photocatalytic water splitting and organic matter degradation. Finally, it offers a preview of the development paths and opportunities for BiVO4-based heterojunction nanomaterials in the future. This comprehensive assessment of BiVO4-based heterojunctions provides insightful knowledge to researchers in materials science, chemistry, and environmental engineering that will drive advances and breakthroughs in these important fields.

Ternary heterostructure-driven photoinduced electron-hole separation enhanced oxidative stress for triple-negative breast cancer therapy

Zinc oxide nanoparticles (ZnO NPs) stand as among the most significant metal oxide nanoparticles in trigger the formation of reactive oxygen species (ROS) and induce apoptosis. Nevertheless, the utilization of ZnO NPs has been limited by the shallowness of short-wavelength light and the constrained production of ROS. To overcome these limitations, a strategy involves achieving a red shift towards the near-infrared (NIR) light spectrum, promoting the separation and restraining the recombination of electron-hole (e−-h+) pairs. Herein, the hybrid plasmonic system Au@ZnO (AZ) with graphene quantum dots (GQDs) doping (AZG) nano heterostructures is rationally designed for optimal NIR-driven cancer treatment. Significantly, a multifold increase in ROS generation can be achieved through the following creative initiatives: (i) plasmonic Au nanorods expands the photocatalytic capabilities of AZG into the NIR domain, offering a foundation for NIR-induced ROS generation for clinical utilization; (ii) elaborate design of mesoporous core-shell AZ structures facilitates the redistribution of electron-hole pairs; (iii) the incorporation GQDs in mesoporous structure could efficiently restrain the recombination of the e−-h+ pairs; (iv) Modification of hyaluronic acid (HA) can enhance CD44 receptor mediated targeted triple-negative breast cancer (TNBC). In addition, the introduced Au NRs present as catalysts for enhancing photothermal therapy (PTT), effectively inducing apoptosis in tumor cells. The resulting HA-modified AZG (AZGH) exhibits efficient hot electron injection and e−-h+ separation, affording unparalleled convenience for ROS production and enabling NIR-induced PDT for the cancer treanment. As a result, our well-designed mesoporous core-shell AZGH hybrid as photosensitizers can exhibit excellent PDT efficacy.

Designed construction of boosted visible-light Z-scheme TiO2/PANI/Cu2O heterojunction with elaborated photocatalytic degradation of organic dyes

A novel TiO2/polyaniline/Cu2O (T/PANI/Cu) ternary nanocomposite was synthesized via a facile in-situ polymerization of aniline and a one-step solvothermal method. The ternary nanocomposite Ti/PANI/Cu with Z-scheme heterojunction exhibited excellent photocatalytic performance as well as improved stability. The photocatalytic performance of the prepared photocatalysts (T, T/PANI, and T/PANI/Cu) was investigated by the photocatalytic decomposition of Methyl Orange dye (MO) as an organic contaminant using visible light illumination. The T/PANI/Cu ternary nanocomposite revealed the highest degradation efficiency up to 99.5% after 25 min, which is much higher than that of T (47%) and T/PANI (73%). The development of Z-scheme heterojunction is credited with the increased activity and generation of an electric field that led to an improved structure, a wider visible light response range, and a lower rate of electron-hole pair recombination. Based on trapping tests, ·O2−·OH, and h+ species were the main active species involved in the photocatalytic degradation of MO dye. Even after the fifth cycle, the T/PANI/Cu composite remained effective in the successive photocatalytic decomposition of MO, maintaining over 90% of the original degradation efficiency.