Replacement Of TiO2 Research Articles

A calcined aluminum silicate micro-based pigment as titanium dioxide replacement in waterborne coatings

This research is focused on evaluation of kaolin (Calcined Aluminum Silicate) micro-based pigment or filler that can substitute titanium dioxide in waterborne paints. Calcined aluminum silicate has shown ability for partial replacement of titanium dioxide by fractionally and runnability. Titanium dioxide is very essential white pigment that has highest hiding power in waterborne coatings. But titanium dioxide is most expensive pigment. Our purpose was to find inexpensive pigment for replacement of titanium dioxide that does not affect properties of waterborne coatings but reduce cost of titanium dioxide in paint formulation. Fillers or calcined aluminum silicate has effect on properties of coatings like gloss, textures, viscosity, emulsion and tinting or coloring strength of paint. Our research main focus was that these properties of paint will not be affected by replacement of TiO2. To evaluate new pigment five samples are prepared in laboratory using high speed disperser. These samples were prepared at room temperature with same period of time in mixer. One sample is prepared as standard with no replacement of TiO2, other four sample were prepared with TiO2 replacement about 5%, 10%, 15% and 20% in coatings. Additives, binder and fillers were added according to paint basic formulation. Tests includes gloss, appearance, opacity, density, viscosity, smoothness, scrub resistance and whiteness or brightness. Results of these samples show that calcined aluminum silicate has potential to replace titanium dioxide in paint. The rheological, optical, mechanical and weathering properties were studied. Other properties like gloss, opacity, density, viscosity, brightness, scrub resistance, brushability, light fastness and reflectivity values were in range. In our study it is shown that titanium dioxide can be replaced from 5% to 20% in waterborne coatings without any effect on properties of paint. Replacement of titanium dioxide give better quality and economically favorable.

Effect of semiconductor materials on anaerobic methanogenesis of terephthalic acid: Promotion and inhibition mechanisms

AbstractThe treatment of purified terephthalic acid wastewaters via anaerobic methods poses a significant challenge due to the slow degradation rate and extended reaction time required for the most recalcitrant terephthalic acid (TA). To address this challenge, this study investigated the efficacy of various semiconductors in promoting TA degradation and determined their respective functional roles. Results showed that the addition of g‐C3N4 increased methane production by 28.38%, indicating its potential as a replacement for TiO2 in TA degradation. The improvement was attributed to the intensified direct interspecies electron transfer (DIET) process, facilitated by microorganisms that directly utilize conductive TiO2/g‐C3N4 as intermediaries to accelerate the electron transfer rate. The unfavorable methanogenesis performances of CeO2 and Fe2O3 were accredited to agglomeration phenomena and toxic effects. This study provides insights into the roles of exogenous materials in promoting or limiting the DIET process, and offers an environmentally friendly and highly‐effective strategy for treating industrial purified‐terephthalic acid wastewater.

Solar cell capacitance simulation and experimental photovoltaic performance analysis of perovskite solar cell based on CsGeI3

In this study, the experimental results of the perovskite solar cell with FTO/TiO2/CsGeI3/spiro-OMeTAD/Pt cell architecture are compared with the simulated results obtained using SCAPS-1D. Optimizations have been carried out by changing TiO2 ETL with CdS and Cd0.5Zn0.5S and spiro-OMeTAD HTL with inorganic CuI, Cu2O, CuSCN and NiO, thickness of perovskite, ETL, HTL and the temperature to formulate a high-performance perovskite solar cell. The impact of varying absorber thickness, ETL and temperature exhibit very minimal or no change. However, the simulated device exhibits high power conversion (4.94% to 7.12%) efficiency by replacement of TiO2 with Cd0.5Zn0.5S. Further, the impact of change of inorganic HTLs have also been studied by considering Cd0.5Zn0.5S as ETL. All inorganic HTLs outperformed well with almost similar cell efficiency (∼19.9%); NiO being highest. Therefore, analyzing all the results, we suggest that to draw a high-power conversion efficiency Cd0.5Zn0.5S shall be chosen as ETL possessing 95 nm layer thickness, 10 nm thick NiO as HTL and keep the absorber thickness 795 nm. Thus, the structure of the simulated solar cell device FTO/Cd0.5Zn0.5S/CsGeI3/NiO/Pt having such cell characteristics can be considered in the manufacturing workflow for its mass-scale production.

An Experimental Investigation on the Steel Fiber Concrete by Partial Replacement of Tio2 and Quartz Powder

Concrete is a building material widely used in the world for every construction project, and this construction projects consists of every possible challenge in terms of durability, exposure to various reactive substances and at a place where concrete needs to be high strength. the concrete is a mixture which is of heterogeneous aimed to solidify and produce strength based on the quality and composition of materials used in the concrete. in this study we are performing an experimental investigation to see whether there is any possible increase in the strength of nominal concrete to change to high strength concrete, In order to achieve this high strength we have used materials like steel fibres, TiO2 as partial replacement for cement, quartz powder as partial replacement of fine aggregate. We have performed several tests on materials, fresh concrete, and hardened concrete. We have also reviewed the previous works of the researches performed on the similar projects with the related materials. we have used a varied percentages of material ratios as 10%, 20%, 30%, 40%, 50% of quartz powder partially replacing fine aggregate, and 0%, 0.5%, 1.0%, 1.5% of TiO2 as partial replacement of cement, and 0%, 0.5%%, 1%, 1.5%, 2% of steel fibres addition to concrete.

A novel dense Al2O3-Ti2O3 slag synthesized while ferro-titanium alloy making

ABSTRACT This paper describes the preparation route and formation mechanism of a Al2O3–Ti2O3 composite. During the fabrication of a ferro-titanium alloy from titanium concentrate via a thermite method, CaO is generally added to reduce the viscosity of the liquid and promote the separation of the ferro-titanium alloy and Al2O3–CaO–TiO2 slag. The latter represents a multi-oxide system mainly composed of CaAl12O19, CaAl4O7, and CaTiO3 species with poor high-temperature performance, which considerably limits its practical application. The performance optimization and high value-added application of this slag involve the elimination of the CaO phase and replacement of TiO2 with Ti2O3 particles to prevent the formation of a multi-oxide system due to the low solubility of Ti2O3 in Al2O3. The Al2O3–Ti2O3 composite material was successfully prepared via industrial experiments, and its synthesis mechanism and corresponding reaction model are established.

Investigating the Effect of ZnSe (ETM) and Cu2O (HTM) on Absorber Layer on the Performance of Pervoskite Solar Cell Using SCAPS-1D

Tin perovskite (CH3NH3SnI3) have attracted a lot of attention and could be a viable alternative material to replace lead perovskite in thin film solar cells. A detailed understanding on the effects of each component of a solar cell on its output performance is needed to further develop the technology. In this work, a numerical simulation of a planar hetero-junction tin based perovskite solar cell using Solar Cell Capacitance Simulator (SCAPS) to study some parameters that can influence the performance of tin PSC with Cu2O as HTL and ZnSe as ETL performed. The thickness of absorber material, ETL and HTL, the bandgap of absorber material and ETL was investigated. Results revealed that the thickness and bandgap of the absorber material and ETL of ZnSe strongly influence the PCE of the device. The performance of the cell increases with reduction in thickness of ZnSe. ZnSe is found to be a replacement for TiO2 which is expensive. Cuprous oxide of HTL in tin based PSC is efficient and better than the expensive spiro-MeOTAD which is easily degradable. Furthermore, results of simulation and optimization of various thicknesses indicates that ZnSe has a PCE of 21.11%, FF of 68.33%, JSC of 33.51mA/cm2 and VOC of 0.92V. These values slightly increase after optimization of parameters to PCE of 22.28%, FF of 70.94%, JSC of 31.01mA/cm2 and VOC of 1.01V.

A comparative study of different ETMs in perovskite solar cell with inorganic copper iodide as HTM

Perovskite solar cells (PSCs) research is substantially increasing because of the fast improvement in their power conversion efficiency (PCE), cheapness, possibility to tune the bandgap, low recombination rate, high open circuit voltage, excellent ambipolar charge carrier transport and strong and broad optical absorption. In this paper, different electron transport materials (ETMs) have been analyzed with a new Copper Iodide (CuI) Hole Transport Material (HTM) to replace the conventional hole and electron transport materials for PSCs, such as TiO2 and Spiro-OMeTAD which have been known to be susceptible to light induced degradation. Moreover, the influence of the ETL, HTL and the perovskite layer thicknesses on the overall cell performance, is studied. The design of the proposed PSC is performed utilizing SCAPS-1D simulator (Solar Cell Capacitance Simulator-one dimension). Because of its high electron affinity and tunable bandgap, ZnOS is found to be the best replacement for TiO2. The results show that lead-based PSC with CuI as HTM is an efficient arrangement and better than the easily degradable and expensive Spiro-OMeTAD. According to the presented simulation and optimization of various layers thicknesses, the highest designed efficiency is 26.11%.

Structure-based viscosity model development for titania aluminosilicate slags

ABSTRACTBased on the structure of melts, a model has been developed that estimates the viscosity of the fully liquid melts in the CaO–MgO–Al2O3–SiO2–TiO2 systems. Three kinds of tetrahedral ([SiO4]4−, [AlO4]5−, and [TiO4]4−) are considered in the titania aluminosilicate slag. According to the hole theory of melts, this model provides a link between the viscosity and the structures of the melts. The present model is capable of predicting the viscosities in the CaO–MgO-–Al2O3–SiO2–TiO2 systems with wide composition and temperature ranges above liquidus; the average of relative errors for this model was approximately 20.0%. From the model calculation results, the addition of TiO2 decrease the viscosity of slag under non-reducing atmosphere. The ability of increasing viscosity follows the order: SiO2> Al2O3> TiO2> CaO. Due to the charge compensation and unit size effect, the replacement of TiO2 by Al2O3 will result in the increase of viscosity.

High-performance planar perovskite solar cells based on low-temperature solution-processed well-crystalline SnO2 nanorods electron-transporting layers

Low-temperature solution-processed method is a kind of low-energy-consuming and simple methodology for preparing cost-effective planar perovskite solar cells (PSCs). A key factor affecting photovoltaic performance of planar PSCs is the quality of electron-transporting layers (ETLs) in the devices. Although TiO2 is the most widely used material for preparing ETLs, it has drawbacks such as low electron mobility and ultraviolet light induced photocatalysis. So the replacement of TiO2 in ETLs is an important strategy to improve the stability and photovoltaic performance of PSCs. Here, the fabrication of high-performance planar PSCs based on low-temperature solution-processed well-crystalline SnO2 nanorods ETLs is reported. The sophisticated solvothermal method with the aid of oleic acid (OA) ligands is used to synthesize high aspect ratio and well crystalline SnO2 nanorods. And then the OA-capped SnO2 nanorods are directly used to fabricate ETLs without complex treatments. The planar PSCs based on OA-capped SnO2 nanorods ETLs achieve a champion power conversion efficiency of 18.62%, which is much higher than that of the ones based on OA-capped TiO2 nanorods ETLs (14.27%). Compared to the OA-capped TiO2 nanorods, the insulating OA ligands show weaker influence on the electronic properties of SnO2 nanorods, owing to the high electron mobility character of SnO2.

Promoted catalysts for hydrogenation of bicyclic aromatic hydrocarbons obtained in situ from molybdenum and tungsten carbonyls

Promoted Мo and W catalysts have been prepared in situ via thermal decomposition of precursors, oil-soluble salts Mo(CO)6, W(CO)6, С°C16H30O4, and NiC16H30O4. TiO2, Al2O3, and ZrO(NO3)2 · 6H2O have been used as the acidic additives. Also, Mo and W unsupported sulfide catalysts have been prepared in the presence of elemental sulfur as the sulfiding agent. The catalysts have been characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. The activity of the catalysts prepared in situ has been evaluated in the hydrogenation reaction of bicyclic aromatic hydrocarbons by the example of model mixtures of 10% solutions of naphthalenes (unsubstituted naphthalene, 1- and 2-methylnaphthalenes, and 1,5- and 2,3-dimethylnaphthalenes) in n-hexadecane. The effect of the precursor/acidic oxide ratio on the activity of the formed catalyst has been found. Hydrogenation of bicyclic aromatic hydrocarbons has been conducted at a hydrogen pressure of 2 and 5 MPa and a temperature of 380 and 400°C for 2 h. Hydrogenation of the unsubstituted aromatic ring has been preferable due to the absence of steric hindrances. The degree of conversion of n-hexadecane under the reaction conditions has been 1.5–7.5% depending on the reaction temperature. It has been found that the activity of the sulfided catalyst in the conversion of 1- and 2-methylnaphthalenes is inferior to the activity of the unsulfided analogue, while partial replacement of TiO2 by Al2O3 results in a decrease in the conversion of the substrates as opposed to the unsulfided catalysts, in which the use of nanocrystalline Al2O3 promotes an increase in the conversion.

Cornelius to deliver extender products as a replacement for TiO2

Cornelius to deliver extender products as a replacement for TiO2

Effect of slag variations on ANSI/AWS A5.1–91 E6013 electrode properties: replacement of TiO2 in electrode coating with MnO, FeO, CaO, MgO, K2O, or Na2O

The present work is part of a research programme to study the effect of variation of the coating composition of covered rutile manual electrodes on both operational and deposited weld metal properties. According to previous results obtained for rutile electrodes, an increase of slag basicity, achieved through modifications in the coating, produces an improvement of the impact properties of the deposited weld metal, as well as a decrease in the diffusible hydrogen, along with beneficial changes in the operational properties of the electrode. The aim of the present work is to study the influence of the replacement of titanium oxide with oxides of alkali metals (sodium and potassium), alkaline earth metals (calcium and magnesium), and iron and manganese oxides in the coating of an ANSI/AWS A5.1–91 E6013 type electrode on the operational characteristics of the electrode and the microstructure, mechanical properties, and diffusible hydrogen content of the electrode weld metal. Tensile strength and Charpy V notch impact properties were measured in the all weld metal samples produced using each of the seven electrodes designed for the present study. A cross-section from each coupon was used to determine the chemical composition of the deposit and to carry out a metallographic study using a light microscope. As a result of the addition of different oxides, changes in the operational properties were observed using both direct and alternating current, as well as a decrease in the diffusible hydrogen content in the weld metal. Also, electrodes in which rutile was substituted by sodium oxide in the coating showed an improvement in the impact properties of the deposit.

Faradaic impedance investigation of the deactivation mechanism of Ir-based ceramic oxides containing TiO2 and SnO2

Ti-supported IrO2/SnO2/TiO2 coatings were prepared by thermal decomposition of the chloride precursor mixtures (400 C). The eAect of the replacement of TiO2 by SnO2 on the service life of the Ti/IrO2 + TiO2 coating was investigated under galvanostatic polarization at 0.8 A cm ˇ2 in 1.0 mol dm ˇ3 HClO4. The deactivation mechanism of the electrodes, using OER as the reaction model, was investigated through the periodic recording of voltammetric curves (VC) and impedance spectra (EIS) as a function of the anodization time. Bulk composition and morphology of the electrode coatings were investigated by energy dispersive X-ray (EDX) and scanning electron microscopy (SEM) before and after accelerated life tests. The service life showed a dependence on the electrode composition. Replacement of TiO2 by SnO2 in the Ir0:3Ti0:7O2 electrode led to a decrease in the service life of these systems above 30% mol SnO2 content. This behaviour is directly related to morphological factors and the absence of synergetic eAects. The behaviour of the parameters supplied by the EIS, VC, SEM, and EDX analyses made it possible to describe the overall deactivation mechanism.

Self-opacifying aluminum phosphate particles for paint film pigmentation

Opaque particles of aluminum phosphate can be obtained in two ways: self-opacification within drying latex films and thermal treatment at 500–700°C (which was previously described). Self-opacification is easily achieved and allows for extensive replacement of TiO2 as a white pigment, with a gain (in an acrylic latex) in the optical properties of the pigmented film.

Electrocatalytic properties of ternary oxide mixtures of composition Ru0.3Ti(0.7−x)CexO2: oxygen evolution from acidic solution

Mixed oxide electrodes of general composition Ru0.3Ti(0.7−x)Ce x O2 were prepared by thermal decomposition of the respective chlorides using Ti as a support. x was varied between 0 and 70 mol %. Oxygen evolution was used as a model reaction to investigate the dependence of the electrocatalytic properties on oxide composition. Kinetics was studied by quasistationary current-potential curves and reaction order determination. A minimum Tafel slope of about 30 mV has been found in the 10–30% CeO2 composition range. On the basis of a zero reaction order at constant overpotential, a reaction mechanism has been proposed accounting for the composition dependence of the Tafel slope. It has been concluded that the replacement of TiO2 with CeO2 brings about an increase in the electrocatalytic activity for oxygen evolution, while the layer becomes more prone to mechanical erosion.

Morphology of (Ru-Ti-Sn) mixed-oxide coatings

Noble-metal-oxide-based coatings have successfully replaced many of the conventional anode materials in industrial electrochemical processes. The performance characteristics of these mixed-oxide electrodes have been found to be improved by the inclusion of non-noble-metal-oxide components. Of these, the addition of SnO2 to RuO2-TiO2 has attracted much attention. In the present paper, the morphology change imparted by gradual replacement of TiO2 by SnO2 from the RuO2-TiO2 (30/70) coatings is reported. Scanning electron microscopic examination and porosity determination reveal that significant modifications take place in the surface structure, and the surface layer tends to become compact at SnO2 concentration above 30 mol % SnO2.