Search or ask a question

Why tio2 is used as photocatalyst although high band gap?

Best insight from top research papers

Titanium dioxide (TiO2) is utilized as a photocatalyst despite its high band gap energy due to its exceptional properties. TiO2 is cost-effective, chemically stable, environmentally friendly, and has low toxicity. Although its band gap energy restricts its activation to UV light, various strategies have been developed to enhance its visible light activity, such as heterostructure formation and element doping. Additionally, the synthesis of hydrogenated titanium dioxide nanorods has been shown to narrow the band gap of TiO2, making it more responsive to visible light. These advancements in TiO2 photocatalysis have significantly expanded its applications for environmental remediation and renewable energy production, making it a promising candidate despite its high band gap energy.

Answers from top 5 papers

PDF

Open Access

More filters

Papers (5)	Insight
Open access•Journal Article•DOI Preparation and Photocatalytic Activities of TiO2-Based Composite Catalysts Hua Yang, Beibei Yan, Wei Chen, Junjiao Yang - Show less +3 more 17 Oct 2022-Catalysts 9 Citations	TiO2 is used as a photocatalyst despite its high band gap of 3.2 eV because it efficiently degrades pollutants under UV light, making it cost-effective and environmentally friendly.
Open access•Journal Article•DOI Recent update on photocatalytic degradation of pollutants in waste water using TiO2-based heterostructured materials Nawal Madkhali, Cheera Prasad, Kuruma Malkappa, Hyeong Yeol Choi, Varadhi Govinda, Indra Bahadur, Rasha A. AbuMousa - Show less +6 more 01 Jan 2023-Results in engineering 7 Citations	TiO2 is used as a photocatalyst despite its high band gap because it can be modified to enhance visible light activity, enabling efficient degradation of pollutants in wastewater.
Journal Article•DOI Enhancement of visible-light photo-activity of TiO2 arrays for environmental water purification A. Baqaei, A. A. Sabbagh Alvani, H. Sameie - Show less +2 more 29 Jul 2022-Pigment & Resin Technology 1 Citations	TiO2 is used as a photocatalyst despite its high band gap due to its strong optical absorptivity, stability, and low cost, with nanostructuring enhancing visible light absorption and photocatalytic activity.
Book Chapter•DOI Titanium Dioxide Photocatalysts for Environmental Applications Metal-Doping with Cerium Ions for Visible Light Activation and Efficiency Improvement 24 Feb 2023	Titanium dioxide (TiO2) is used as a photocatalyst despite its high band gap because it can generate electron-hole pairs upon light absorption, initiating photocatalytic reactions efficiently.
Open access•Journal Article•DOI Use of TiO2 in Photocatalysis for Air Purification and Wastewater Treatment: A Review Seba Mohammed, Zainab Y. Shnain, Muhammad Abid - Show less +2 more 01 Sep 2022-Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā 1 Citations	TiO2 is used as a photocatalyst despite its high band gap because modifications enhance its visible light absorption, expanding its applications for environmental treatment processes.

My columns

Related Questions

Photocatalytic hydrogen production bandgap tio2 ?4 answersPhotocatalytic hydrogen production using TiO2 as a catalyst is a promising approach for clean energy generation. TiO2, a widely studied photocatalyst, possesses a wide band gap of around 3.2 eV, limiting its efficiency to only ultraviolet light. Various strategies have been explored to enhance TiO2's photocatalytic activity, including band shape engineering through methods like oxygen defect introduction and Cl-doping. Additionally, the coupling of TiO2 with SrTiO3 has shown to improve charge carrier separation and enhance photocatalytic performance significantly. Furthermore, surface modifications like peroxo-titania formation through H2O2 exfoliation have been demonstrated to reduce the band gap of TiO2, leading to increased hydrogen production. These advancements highlight the ongoing efforts to optimize TiO2 for efficient photocatalytic hydrogen production.

How can the band gap of TiO2 change but not the crystal structure?5 answersThe band gap of TiO2 can change without altering the crystal structure due to factors like coordination number, surface hydroxylation, and doping levels. For instance, different polymorphs of TiO2 exhibit varying band gaps, with ε-TiO2 being a metal, while δ- and ζ-TiO2 are semiconductors with distinct band gap values. Additionally, the optical band gap of TiO2 powders can be controlled by the fuel used in the synthesis process, impacting their photo catalytic activity. Moreover, the addition of biochar to TiO2 thin layers influences the band gap energy, showcasing variations without affecting the crystal structure. Furthermore, surface hydroxylation can lead to the formation of "crystalikes," non-crystalline TiO2 nanoparticles with similar electronic properties to crystalline counterparts, showcasing how band gaps can change independently of crystal structure.

Why tio2 is best for photocatalytic activity?5 answersTitanium dioxide (TiO2) is considered the best material for photocatalytic activity due to several reasons. Firstly, TiO2 is an excellent photocatalyst that can degrade pollutants in an environmentally friendly manner. It has high chemical stability, low toxicity, low operating costs, and environmental friendliness. TiO2 is a semiconductor material with a bandgap of 3.2 eV, allowing it to generate photoelectrons and photogenerated holes when exposed to ultraviolet light. Additionally, TiO2 nanoparticles have exceptional physicochemical properties, making them suitable for various industrial processes. To enhance the photocatalytic efficiency of TiO2, researchers have explored methods such as element doping and modifying its optical and electronic properties. The anatase phase of TiO2 has been found to exhibit higher photocatalytic activity compared to other phases, attributed to its increased density of surface hydroxyls and mobility of electron-hole pairs. Furthermore, the synthesis of colored titania, such as black TiO2, with surface defects and oxygen vacancies, has shown promising photocatalytic activity. Nitrogen doping has also been effective in activating TiO2 under visible light.

What is the actual bandgap for TiO2?5 answersThe bandgap energy of TiO2 varies depending on the specific conditions and modifications. TiO2 has a bandgap energy of 3.27 eV. However, when TiO2 is deposited with curcumin and metal-curcumin compounds, the bandgap energy decreases. TiO2/curcumin has a bandgap energy of 2.82 eV, while TiO2/Na+-curcumin, TiO2/Mg2+-curcumin, and TiO2/Cu2+-curcumin have bandgap energies of 2.36, 3.11, and 2.15 eV, respectively. Additionally, TiO2 with super narrow bandgap (1.1 eV∼) can be synthesized through a one-step single-mode magnetic microwave induced plasma treatment, with selectively surface Ti3+-doping to enhance visible-light photocatalytic performance. Furthermore, TiO2 can have a significantly reduced bandgap energy when combined with reduced graphene oxide (rGO), resulting in a wide broadband absorption range from 700 to 10,000 nm. Doping TiO2 with Pd can also narrow the bandgap and increase its photocatalytic activity in the visible region.

Why does TiO2 have photocatalytic properties?1 answersTiO2 has photocatalytic properties because it can absorb light energy and use it to initiate chemical reactions that degrade organic pollutants. The photocatalytic activity of TiO2 is attributed to its unique electronic structure and surface properties. When TiO2 is exposed to light, the energy from the photons is absorbed by the TiO2, promoting electrons from the valence band to the conduction band, creating electron-hole pairs. These electron-hole pairs can react with water and oxygen molecules adsorbed on the TiO2 surface, leading to the generation of reactive oxygen species (ROS) such as hydroxyl radicals. These ROS are highly reactive and can oxidize and degrade organic pollutants into harmless byproducts. Additionally, TiO2 has a large surface area and can adsorb organic pollutants onto its surface, enhancing the photocatalytic degradation process.

Whats the prppreties of TiO22 answersTiO2 has several properties that make it a preferred material for various applications. It is chemically inert, non-toxic, and safe for humans and the environment. TiO2 exhibits high photocatalytic activity, making it suitable for use in environmental clean-up processes. It also has a high dielectric constant, which remains constant even with decreasing physical thickness. TiO2 can be doped with other materials, such as ErXYbYLiZTiHO2, to enhance its functionality. Doped TiO2 materials can be used as an interface modification layer, reducing the recombination process of photogenerated charges and improving the conversion efficiency of perovskite solar cells. TiO2 can also be modified with metal oxide nano clusters to achieve visible light absorption and improved photocatalytic activity. Overall, TiO2 possesses a combination of properties that make it versatile and suitable for various applications.

See what other people are reading

What is the current state of research on the use of conjugated microporous polymers for electrocatalytic CO2 reduction?

Current research on conjugated microporous polymers (CMPs) for electrocatalytic CO2 reduction shows promising advancements. Studies have synthesized CMPs like TEB-BPY, Py-BSU, and TBN-BSU with high thermal stability and surface areas suitable for gas adsorption and electrochemical applications. Additionally, the integration of molecular catalysts like cobalt porphyrin into CMPs has enhanced CO2 reduction efficiency by improving electron transfer pathways and redox kinetics, achieving high faradic efficiencies for CO production. Furthermore, the design of CPs with enhanced charge transfer efficiency and surface modifications has led to improved photocatalytic CO2 conversion rates, with selectivity ranging from CO to CH4. These findings highlight the potential of CMPs and CPs as efficient materials for electrocatalytic CO2 reduction, paving the way for sustainable carbon cycle management.What are the underlying mechanisms that give rise to the distinctive optical properties of metal oxides?

The distinctive optical properties of metal oxides stem from their unique structural and compositional characteristics. Metal oxides, abundant in the Earth's crust, exhibit tunable electronic and optical properties based on factors like synthesis techniques, morphology, and defect states, enabling the development of materials with novel functions. In the realm of photovoltaics, metal oxides play a crucial role due to their optical, electrical, and chemical properties, making them ideal for various solar cell components like back contacts, absorbers, and transparent conductive oxide layers. Doping metal oxides with transition and rare-earth metals further refines their optical bandgap and dielectric parameters, enhancing their conductivity for applications in optoelectronics and technologies like light-emitting diodes and photocatalysis. The optical properties of metal nanoparticles coated with oxide layers are also influenced by electron-scattering mechanisms, impacting their polarizability and extinction coefficients.Does natural zeolite functionalized with silver nanoparticles kill bacteria Escherichia coli?

Natural zeolite functionalized with silver nanoparticles has shown promising antibacterial properties against Escherichia coli. Studies have demonstrated that silver-modified zeolites exhibit bactericidal activity against E. coli, with varying effectiveness based on the specific conditions of the synthesis process. The presence of silver ions and nanoparticles within the zeolite structure contributes to the antibacterial performance, with different zeolite matrices affecting the release and efficacy of the silver component. Furthermore, the size and morphology of the silver nanoparticles on the zeolite surface play a role in enhancing the antibacterial efficiency, with Na-modified zeolite-based composites showing particularly high activity against E. coli. Overall, natural zeolite functionalized with silver nanoparticles demonstrates significant potential in combating bacterial contamination, especially against Escherichia coli.What is polypropylene microplastic?

Polypropylene microplastics are tiny plastic particles made of polypropylene polymer, a common thermoplastic material. These microplastics pose a significant environmental threat due to their widespread presence in various ecosystems. Polypropylene is extensively used in industries like automotive for its toughness and stiffness, often blended with elastomers or fillers to enhance its properties. Research has shown that polypropylene microplastics can be degraded using methods like biodegradation by specific bacteria, leading to weight loss and structural changes in the microplastics. Additionally, polypropylene plastic particles have been developed with specific compositions to enhance properties like flame retardancy and mechanical strength. Overall, polypropylene microplastics are a concerning environmental pollutant that requires effective management strategies.What's the effect Fe2 /fe3 ratio in fenton ?

The Fe2/Fe3 ratio in Fenton systems plays a crucial role in the efficiency of pollutant degradation. Research has shown that the presence of Fe2+ ions can significantly enhance the decomposition of H2O2 to form reactive ·OH species for the degradation of dye pollutants, such as methylene blue and Rhodamine B. Additionally, the Fe2O3/TiO2 functionalized biochar demonstrated high degradation efficiency for dye pollutants, with Fe2O3 contributing to the rapid degradation of organic pollutants via Fenton reactions. Moreover, the Fe2O3/TiO2/reduced graphene oxide nanocomposite exhibited enhanced synergetic cooperation between photocatalysis and Fenton reactions, leading to high mineralization efficiency of organic pollutants. Therefore, maintaining an optimal Fe2/Fe3 ratio is essential for maximizing the effectiveness of Fenton systems in pollutant degradation.What are the recent advancements in machine learning techniques for optimizing perovskite solar cell efficiency?

Recent advancements in machine learning (ML) techniques have significantly contributed to optimizing perovskite solar cell (PSC) efficiency, addressing various challenges from material selection to device fabrication and performance prediction. Machine learning models, including linear regression, neural networks, deep learning, and statistical forecasting, have been employed to tackle issues in hybrid organic–inorganic perovskite (HOIP) solar cell production steps, such as composition screening, fabrication, material stability, and device performance. These models benefit from high-throughput experimentation, which provides the vast amount of training data required for effective implementation. In the optimization of PSC efficiency, one study focused on the thickness of the methylammonium-free absorber layer, demonstrating that optimizing this parameter can significantly increase PSC efficiency. Similarly, machine learning has been used to predict the bandgaps of diverse perovskite material compositions, crucial for developing high-efficiency indoor PSCs (IPSCs). Traditional machine learning models and structure-based graph neural network (GNN) models have been designed to forecast various characteristics of perovskite materials, with GNN models showing exceptional performance in predicting properties when sufficient data is available. Moreover, a systematic machine learning workflow coupled with high-throughput density functional theory (DFT) calculation has been employed to predict potential two-dimensional lead-free halide perovskite materials with appropriate band gap and stability for solar cell applications. A simulation survey using the Solar Cell Capacitance Simulator (SCAPS-1D) and machine learning models has analyzed the effect of different hole transport layers (HTLs) and perovskite active layers (ALs) on solar cells’ performance, identifying configurations that yield high power conversion efficiency (PCE). Machine learning has also been applied to interface passivation, using an ML model to investigate the relationship between the molecular features of ammonium salts and the PCE improvement of PSCs. Additionally, the potential energy surface (PES) and phase transition kinetics of perovskites have been studied to understand and modulate transition dynamics, extending the lifetime of perovskite materials. These advancements underscore the pivotal role of machine learning in enhancing the efficiency and stability of perovskite solar cells, paving the way for the development of more efficient and durable photovoltaic devices.What are the effects of ball milling on the morphology of particles?

Ball milling has diverse effects on particle morphology based on different materials and processing conditions. The studies reveal that ball milling can lead to changes in particle size, shape, and structure. For instance, in the case of copper ore, varying grinding times and ball loads result in different particle shapes and sizes, affecting recovery and fractal dimensions. Similarly, in the milling of an Al-Mn-Cu-based alloy, the treatment time influences granule coarsening and phase composition, with nanodiamond particles impacting microstructure and hardness. Furthermore, ball milling of Ni powder in different atmospheres alters grain and particle sizes, with oxygen adsorption playing a crucial role in refining the powder. Overall, ball milling is a versatile technique that can significantly modify the morphology of particles in various materials.How does deposition time influence the SnO2:f film?

Deposition time significantly impacts the properties of SnO2:f thin films. Studies show that longer deposition times lead to secondary growth, affecting carrier density and film morphology. Additionally, varying deposition times during the synthesis of SnO2 thin films result in changes in film thickness, porosity, and sensitivity to LPG, with films deposited at higher temperatures exhibiting decreased sensitivity. Furthermore, for FTO thin films, increasing the number of deposition cycles and annealing temperature results in larger crystallite size, lower dislocation density, improved electron mobility, decreased resistivity, and reduced transparency. These findings collectively demonstrate that deposition time plays a crucial role in determining the structural, morphological, and electrical properties of SnO2:f thin films.Can unpaired electron help in electron transfer?

Unpaired electrons play a crucial role in electron transfer processes. Research has shown that unpaired electrons can stabilize key intermediates, alter reaction pathways, and enhance charge separation to facilitate efficient electron transfer. For instance, unpaired electron engineering in TiO2 has been demonstrated to significantly increase electron-consumption rates and CH4 selectivity in photocatalytic reactions. Additionally, the electronic structure of Fe3+ ions undergoes multistep electron transfers to form high-valent Fe4+ ions, highlighting the importance of unpaired electrons in spin conversion processes. Furthermore, the exposed sulfur atom in c-type cytochromes facilitates electron transfer by delocalizing porphyrin and Fe(III) d orbitals onto it, enhancing electron transfer capabilities. Overall, unpaired electrons can indeed aid in electron transfer by influencing reaction pathways, stabilizing intermediates, and enhancing charge separation.Fumarate or fumaric acid based linear polyester biomaterials?

Fumarate and fumaric acid are essential components in the synthesis of linear polyester biomaterials. Fumaric acid, derived from petroleum resources, serves as a crucial raw material for unsaturated polyester resins. On the other hand, fumarate, a useful unsaturated dicarboxylic acid, is utilized in the production of polyesters, polyhydric alcohols, and as a mordant for dyes. Additionally, a new family of bio-based linear polyesters has been developed from oleic acid through efficient chemical pathways, showcasing the potential for bio-based materials in polyester synthesis. Furthermore, novel linear polyester resins can be created by condensing polyols with polyfunctional acids derived from biobased materials or biological feedstock, expanding the possibilities for sustainable polyester biomaterials.Does the ultrasonic bath destroy the coating of citrate-coated nanoparticles?

The ultrasonic bath does not destroy the coating of citrate-coated nanoparticles; instead, it plays a crucial role in their formation and dispersion. Ultrasonication assists in the formation of nanomaterials, triggering the subsequent formation of nanostructured materials like nanorods of α-Fe2O3. High-power ultrasound is highly efficient in breaking down agglomerates and aggregates of nanoparticles, enhancing dispersion. In the case of citrate-coated magnetite nanoparticles, ultrasonic agitation affects the size of aggregates formed, but the citrate shell remains intact. The ultrasonic bath, when used for synthesizing gold nanoparticles, results in monodispersed spherical nanoparticles without affecting the citrate coating. Therefore, the ultrasonic bath is a valuable tool for nanoparticle synthesis and dispersion without damaging the coatings.