TiCl4 Research Articles

Enhance the performance of dye-sensitized solar cells with effective compact layers and direct contact cell structure

Compact layers (CLs) characterized by dense structures play a crucial role in enhancing the power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs). Previous studies focus on preparing CLs using a single precursor through one-step methods. In this study, the new CLs are prepared by sequentially depositing films using titanium tetrachloride and titanium diisopropoxide bis(acetylacetonate) via chemical bath deposition and spray pyrolysis, respectively. Scanning electron microscope images show that the resulting CL has a denser structure compared to those prepared by one-step methods. Moreover, electrochemical impedance analysis indicates that they can efficiently inhibit charge recombination at the interface, leading to higher PCE. Furthermore, when the CL and direct contact (DC) structure are applied simultaneously to fabricate the DSSCs using Y123 dye and Co2+/3+ electrolyte, efficiencies of 9.86 % and 24.74 % can be obtained respectively, under one-sun and room light conditions (200 lx). Additionally, tandem cells using the DC structure for both top and bottom cells can achieve an efficiency of 29.68 % under room light illumination of 200 lx.

Stoichiometry Dependence in the Consecutive, Competing Reduction, Halogenation, or Deoxygenation of Aryl Carbonyls.

Six fundamental chemical transformations of aryl carbonyls are achieved by properly adjusting the stoichiometry of the borane-amine and titanium tetrachloride reagent system. This set of reagents acts collectively as a hydride donor, Lewis acid catalyst, and halogen source for the reduction of carbonyls to alcohols, reductive halogenation of carbonyls to halides, deoxygenation of carbonyls to alkanes, dehydroxyhalogenation of alcohols to halides, deoxygenation of alcohols to alkanes, and hydrodehalogenation of halides to alkanes. While the carbonyl reduction is broadly applicable to both aromatic and aliphatic substrates, the remaining reactions are dependent on the stability of the proposed carbocationic intermediates, enabling highly selective reactions at the substrates' benzylic position. This unique selectivity allows benzylic dehalogenation in the presence of aryl and alkyl halides in addition to highly selective dehydroxyhalogenation of alcohols even for tertiary versus secondary aliphatic and secondary versus primary benzylic substrates using only titanium tetrachloride as the chlorinating agent.

Preparation of Magnesium Titanate by Using Magnesium Chloride a Byproduct of Titanium Plant

This study explores the preparation of magnesium titanate using magnesium chloride, a byproduct of the titanium production plant as a precursor. The synthesis involves the reaction of MgCl2 with titanium tetrachloride under controlled thermal conditions. Initially, MgCl2 and TiCl4 are thoroughly mixed in stoichiometric proportions with an excess of oxalic acid solution to produce magnesium titanyl oxalate. The mixture is then subjected to a calcination process at temperatures ranging from 300 °C to 1000 °C in an oxygen-rich environment. The physicochemical properties of the synthesized MgTiO3 were analyzed using EDS, XRD, TG/DTA, SEM, and particle size analysis. This comprehensive set of analytical techniques provides a thorough understanding of the elemental, structural, thermal, morphological and physical characteristics of magnesium titanate. The formation of pure magnesium titanate is confirmed at temperatures above 800 °C, with lower temperatures leading to the presence of intermediate phases such as MgTi2O5. The synthesized MgTiO3 exhibits a homogeneous microstructure with well-defined grain boundaries, indicating successful preparation of the desired ceramic material.

Microbial Activity of TiO2 NPs via Two Phases Synthesized by The Sol-Gel Method

TiO2 titanium dioxide nano phases of anatase and rutile were controlled only by temperature control of the calcination process, which is a cheap technical technique, and were organized using a sol-gel process, which involved mixing titanium tetrachloride (TiCl4) with ethanol as starting materials, as well as heating at various temperatures (650, 850 ℃ ). The fundamental properties of the as-prepared nanomaterials were investigated using Fourier transform infrared spectra (FTIR). The antibacterial activity of TiO2 was next investigated using two strains of E. coli, Staphylococcus aureus, and Streptococcus bacteria. The TiO2 structure has a dominating phase of 650 °C in addition to rutile at 850 °C, with an average volume of crystalline (D) of 21.9 nm for the anatase phase and 30.41 nm for the rutile phase. According to XRD data, the spherical shape of the rutile phase is clearly evident in the TEM of TiO2 NPs, the tetragonal shape is clearly seen in the anatase, and the calcination process had a major effect on the crystal size. According to FTIR analysis, the majority of peaks are seen between 400 and 700 cm-1 as a result of bending and oscillation lengthening. The studies demonstrated that TiO2, in both protease and rutile forms, is a highly efficient antibacterial that can be used as a self-cleaning exterior to exterior surfaces (windows) as well as in bio-penetration places like hospitals and medical clinics.

Mechanical properties and chloride resistance of ultra-high-performance seawater sea-sand concrete with limestone and calcined clay cement (UHPSSC-LC3) under various curing conditions

Although the application of ultra-high performance seawater sea-sand concrete with limestone calcined clay cement (UHPSSC-LC3) provides a promising solution for sustainable marine structures, research on the mechanical properties of UHPSSC-LC3 is quite limited, and no research has been conducted on its chloride resistance performance. In this study, the effect of four curing regimes (i.e. standard curing, 20 °C seawater curing, 40 °C fresh water curing, and 80 °C fresh water curing) on the compressive and flexural strength of UHPSSC-LC3 is experimentally investigated. Rapid chloride migration test and chloride titration test are conducted to determine the chloride diffusion and distribution of UHPSSC-LC3, considering the effects of curing conditions and calcined clay (CC) dosage. In addition, XRD analysis is performed to show the differences in the composition of UHPC, UHPSSC, and UHPSSC-LC3. The obtained results demonstrate that UHPSSC-LC3 attains higher mechanical strength than UHPC and UHPSSC under various curing conditions. The incorporation of LC3 makes the free chloride concentration of UHPSSC-LC3 close to that of UHPC, especially when the heated water curing is applied. The free chloride concentrations of UHPSSC- LC3 cured with 40 °C and 80 °C water are only 10.1 % and 2.9 % higher, respectively, than that of UHPC cured under standard condition. Besides, UHPSSC-LC3 achieves the lowest chloride ion diffusion rate, which is 40.4 % lower than that of UHPSSC, due to the denser matrix resulting from the carboaluminate products and the pozzolanic effects of the calcined clay. Furthermore, the application of heated water curing regimes is recommended for UHPSSC-LC3 when the early strength and chloride resistance are the main concerns.

Efficient Solution-Phase Dipeptide Synthesis Using Titanium Tetrachloride and Microwave Heating.

Microwaves have been successfully employed in the Lewis acid titanium tetrachloride-assisted synthesis of peptide systems. Dipeptide systems with their amino function differently protected with urethane protecting groups have been synthesized in short periods of time and with high yields. The formation of the peptide bond between the two reacting amino acids was achieved in pyridine by using titanium tetrachloride as a condensing agent and heating the reaction mixture with a microwave reactor. The reaction conditions are compatible with amino acids featuring various side chains and different protecting groups on both the amino function and side chains. Additionally, the substrates retain their chiral integrity after reaction.

Parametric Study of Vanadium Extraction Process from Refining Tailings of Crude Titanium Tetrachloride

The recovery of vanadium from titanium tetrachloride tail residue is a resource-efficient and environment-friendly method for treating hazardous vanadium-containing solid waste. In this study, to maximize the recovery rate of vanadium in the vanadium extraction process, the independent calcination and leaching factors were optimized using response surface methodology, in terms of calcination temperature (750–950 °C), calcination time (60–180 min), leaching liquid–solid ratio (5–25 mL/g), and leaching time (30–150 min). The results revealed that the calcination temperature was the most effective parameter for vanadium recovery, while the liquid–solid ratio was the least effective factor. Additionally, the optimal conditions were identified as a calcination temperature of 937 °C, a calcination time of 150 min, a leaching solid-to-liquid ratio of 17.4 mL/g, and a leaching time of 150 min. The maximum predicted recovery rate of vanadium by the model regression equation reached 93.1% and showed high credibility consistent with the experimental recovery rate of 93%.

Preparation of Biomass-Derived High Specific Surface Area Carbon with Titanium Nitride Nanoparticles for Lithium-Sulfur Batteries

The widespread challenges facing lithium-sulfur batteries, including the low electrical conductivity of sulfur and its species, electrode volume fluctuations during cycling, and the lithium polysulfides shuttle effect, have hindered their commercialization and practical utility [1,2].Our study addresses these issues by incorporating titanium nitride (TiN) nanoparticles onto high specific surface area porous carbon, exploring this composite's potential as both a sulfur cathode host and separator modifier. The synthesis of the carbon/TiN composite involved two key stages: firstly, the in-situ growth of titanium dioxide (TiO2) nanoparticles on the carbon surface utilizing titanium tetrachloride as a precursor; secondly, the conversion of the TiO2 nanoparticles to TiN nanoparticles through carbothermal nitridization (thermal treatment at 1400 ℃ for 4 hours in a nitrogen medium) [3,4].The lithium-sulfur cell employing the prepared C/TiN-25%@S cathode exhibited an initial discharge capacity of 1155 mAh g-1 at 0.2 C, maintaining a capacity exceeding 700 mAh g-1 after 100 cycles. Notably, the lithium-sulfur cell utilizing the C/TiN-25%@S cathode and a C/TiN-modified separator demonstrated enhanced cycling performance, delivering an initial discharge capacity of 1623 mAh g-1 with retention of over 1126 mAh g-1 after 100 charge/discharge cycles at 0.2 C. Acknowledgments This research was funded by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (Grant No. AP19677708).

Titanium tetrafluoride catalysis for the dehydrative conversion of diphenylmethanols to symmetric and unsymmetric ethers.

In contrast to the conversion of diphenylmethanol to the corresponding halides with an equivalent of titanium tetrachloride or -bromide, catalytic (50 mol%) titanium tetrafluoride converts benzhydrols in diethyl ether or dichloromethane to bis(benzhydryl) ethers within 0.5-1 h at room temperature. Cross ether formation with diphenylmethanols and primary aryl or aliphatic alcohols is achieved in the presence of 25 mol% TiF4 in refluxing toluene as solvent. A tentative mechanism involving a carbocation intermediate has been proposed.

Effect of 60Co gamma irradiation on hydrothermally synthesized Ga2O3-Tio2 nanocomposites.

The effect of 60Co gamma irradiation on gallium oxide and titanium oxide (Ga2O3-TiO2) nanocomposites are investigated in the present study. The Ga2O3-TiO2 nanocomposite was synthesized by hydrothermal method at 120°C. The precursors for the synthesis consist of gallium nitrate anhydrous and titanium trichloride along with sodium hydroxide to achieve the pH of 9. The synthesized Ga2O3-TiO2 was subjected to 60Co gamma irradiation for different doses such as 25, 50 and 75kGy. The morphological, optical and microstructural characteristics were studied using scanning electron microscopy, UV-Visible spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy, respectively. The results shows that the gamma irradiation induces significant changes in the Ga2O3-TiO2 microstructure and there is increase in the grain size and bandgap of the nanocomposites.

Microcalorimetric study of the bactericidal action of titanium tetrachloride on the Pseudomonas aeruginosa growth. Potential implications in orthopaedic surgery

With the rising use of metallic implants worldwide, bacterial infection has become a major concern due to its significant impact on patient health and national healthcare budgets. This study aimed to evaluate the sensitivity of Pseudomonas aeruginosa, a common bacterium responsible for implant surgery infections, to different concentrations of titanium tetrachloride (TiCl4) solutions. Microcalorimetry was used to analyze the heat output produced by bacteria metabolism when exposed to TiCl4 at concentrations ranging from 0 to 10 mM, as well as a saturated solution. The inner chamber of the calorimeter was set to the physiological temperature of the human body (309.65 K), and the heat output produced by bacteria metabolism was collected at intervals of 22.2 s for 48 h using a data acquisition and processing system. The data was then represented as thermograms. The results showed that higher concentrations of TiCl4 had a bactericidal effect on the growth of Pseudomonas aeruginosa. This study supports the potential use of higher concentrations of this compound in surgical implants to reduce the risk of infection development due to its bactericidal properties.

Redox kinetics of methylene green: Titanium trichloride as a novel photo redox agent

Redox kinetics of methylene green: Titanium trichloride as a novel photo redox agent

Laser chemical vapor deposition of TiC fibers and tubes

Laser Chemical Vapor Deposition (LCVD) is a process in which fibers are deposited from a gaseous precursor to a solid phase under a traversing laser focal point. Here, we grow titanium carbide (TiC) fibers and tubes dependent upon a hyperbaric hydrogen-rich, hydrogen-balanced, and hydrogen-lean environment referenced to a titanium tetrachloride and ethylene gas mixture under three different laser intensities. X-ray diffraction confirms the deposition of TiC with energy dispersive spectroscopy noting a radial compositional gradient of titanium and carbon in the diameter of the deposit. Depending on the hydrogen concentration, the TiC encased a core carbon-rich fiber or formed a hollow tube, with these formations explained by thermophoresis. Furthermore, depending on the gas mixture and laser intensity, the carbon-rich interior and TiC outer shell exhibited different morphologies that are discussed in terms of growth rate regimes. The collective outcomes demonstrate the complex processing space in forming ceramic materials by LCVD.

[Ti{η5-1-(SiMe3)-3-(R)-C9H5}Cl2(OEt)] half-sandwich complexes: Synthesis, solid-state structure, hirshfeld surface analysis and theoretical studies

Indenyl-titanium trichloride complexes of type [Ti{η5-1-(SiMe3)-3-(R)-C9H5}Cl3] (R = SiMe3 (3a); R = tBu (3b)) were obtained by treatment of Li[1-(SiMe3)-3-(R)-C9H5] (R = SiMe3 (1a); R = tBu (1b)) with titanium tetrachloride (2) in a 1:1 molar ratio in the presence of isopropanol and SOCl2. Compounds [Ti{η5-1-(SiMe3)-3-(R)-C9H5}Cl2(OEt)] (R = SiMe3 (4a); R = tBu (4b)) are accessible by reacting 1a,b (R = SiMe3 (1a); R = tBu (1b)) with TiCl4 (2) in the presence of ethanol and SOCl2, or when 3a,b were treated with equimolar amounts of EtOH in refluxing benzene. Spectroscopic methods and single crystal X-ray diffraction analysis confirmed the piano-stool geometry of 3a and 4b in the solid state. Hirshfeld surface analysis using 2D fingerprint plots of 3a and 4b were conducted to elaborate non-covalent, intermolecular interactions existing in the solid state, which accounted for the strengthening of the crystal lattice. The molecular structures of the 3 and 4 were further investigated by quantum-chemical calculations. The geometries of the compounds were optimized at the B3LYP/6-31G(d)+LANL2DZ level of theory, and their related molecular parameters including frontier orbital energy gap and molecular electrostatic surface potential have also been calculated to better understand their properties.

Synthetic Studies and Structural Aspects of Dinuclear Sulfur Titanium Compounds

AbstractA series of dinuclear sulfur‐bridged titanium derivatives [Ti(η5‐C5Me5)R(μ‐S)]2 (R=NMe2 (1), Ph (2), CH2Ph (3), CH2SiMe3 (4)) has been synthesized from the reaction of [Ti(η5‐C5Me5)Cl(μ‐S)]2 with the corresponding lithium salt or Grignard reagent. Formulation of 1–4 as symmetric dimers has been confirmed by crystallographic studies. The analogous reaction with Mg(C3H5)Cl afforded the paramagnetic mixed‐valence Ti(III)/Ti(IV) compound [{Ti(η5‐C5Me5)(μ‐S)}2(μ‐C3H5)] (5). Contrasting with complexes 1–4, compound 5 exhibits a bridging μ‐CH2CHCH2 fragment between the titanium atoms, which prevents the formation of a planar Ti2S2 core in the solid‐state structure. Complex 1 reacts with SiH3Ph to give [{Ti(η5‐C5Me5)(μ‐S)}2(μ‐NMe2)] (6), a paramagnetic mixed‐valence Ti(III)/Ti(IV) compound, structurally and electronically similar to 5. Under mild conditions, treatment of compounds 3 and 4 with H2 (1 atm) generates quantitatively the Ti(III) tetrametallic sulfide cluster [Ti(η5‐C5Me5)(μ3‐S)]4, along with the corresponding alkane.

Comparison of three titanium-precursors for atomic-layer-deposited TiO2 for passivating contacts on silicon

Atomic layer-deposited (ALD) TiO2 thin films on silicon were deposited using titanium tetrachloride (TiCl4), titanium tetraisopropoxide (TTIP), and tetrakis(dimethylamino)titanium (TDMAT) together with water vapor as the oxidant at temperatures ranging between 75 and 250 °C. The Si surface passivation quality of as-deposited and isothermally annealed samples was compared using photoconductance lifetime measurements in order to calculate their effective surface recombination velocities Seff. A low Seff of 3.9 cm/s (J0s=24fA/cm2) is achieved for as-deposited TiCl4-TiO2 at 75 °C when a chemically grown (i.e., from RCA cleaning) SiOx interface layer is present. Depositing TTIP-TiO2 at 200 °C on a chemically grown SiOx interface layer yields equivalent Seff values; however, in this case, TTIP-TiO2 requires a 5–15 min postdeposition forming gas anneal at 250 °C. In contrast, TDMAT-TiO2 was not found to provide a similar level of passivation with/without a chemically grown SiOx interface layer and postdeposition anneal. Modeling of the effective lifetime curves was used to determine the magnitude of the effective charge densities Qf in the TiO2 films. In all cases, Qf was found to be of the order of ∼1011 q cm−2, meaning field-effect passivation arising from ALD TiO2 is relatively weak. By comparing the material properties of the various TiO2 films using ellipsometry, photothermal deflection spectroscopy, Raman spectroscopy, elastic recoil detection analysis, x-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy, we find experimental support for the role of Cl (in conjunction with hydrogen) playing a beneficial role in passivating dangling bond defects at the Si surface. It is concluded that low deposition temperature TiCl4 processes are advantageous, by providing the lowest Seff without any postanneal and a comparatively high growth per cycle (GPC).

Poly 2-chloroaniline/TiO2 quantum dots for solar and photocatalytic processes of Congo Red dye and industrial wastewater

This study investigates the synthesis and characterization of a poly 2-chloroaniline (PCl-AN)/TiO2 quantum dots (TQD) composite for photocatalytic degradation of Congo Red dye and industrial wastewater treatment. PCl-AN was synthesized via chemical oxidative polymerization of 2-chloroaniline (80 mmol) using ammonium persulfate (80 mmol) as an oxidant. TQD was prepared by a hydrothermal method using 18 mL of titanium tetrachloride and 45 mL of methanol at 80 °C for 24 h. The (PCl-AN)/TQD composite with 8 wt% TQD was fabricated by in-situ polymerization. Characterization techniques including XRD, FTIR, UV–vis, TGA, EDX, and TEM were employed. XRD revealed PCl-AN particle size of 29–40 nm and TQD sizes of 3.1–4.8 nm. TEM showed core-shell (PCl-AN)/TQD structures of 26–30 nm. The band gaps were 3.33 eV (PCl-AN), 2.17 eV (TQD), and 2.30 eV ((PCl-AN)/TQD). Photocatalytic tests using a 150 W xenon lamp (100 mW/cm2, 200–1100 nm) showed (PCl-AN)/TQD achieved 93.56 % Congo Red degradation in 120 mins, outperforming PCl-AN (51.69 %) and TQD (80.96 %). After 5 recycles, degradation rates decreased by 34.32 % (PCl-AN), 18.57 % (TQD), and 26.75 % ((PCl-AN)/TQD). For industrial wastewater with initial COD 5230–7150 ppm, (PCl-AN)/TQD reduced COD to 745–1230 ppm, meeting the <1000 ppm limit. The (PCl-AN)/TQD composite demonstrates promising photocatalytic performance for environmental remediation.

Reactions of Heteroallenes with Salan-based Ti(IV) Complexes: A Joint Experimental and Computational Study.

The reaction of Ti(NMe2)4 with the salan ligand precursor H2N2O2H2 led to the formation of [(L*)Ti(NHMe2)2] (L*=N2O2 4-) that forms [(H2N2O2)TiCl2] upon reaction with two equiv. of Me3SiCl. [(L*)Ti(py)2] was obtained from the reaction of [Ti(NtBu)Cl2(py)3] with the sodium salt H2N2O2Na2. Treatment of [(L*)Ti(NHMe2)2] with two equiv. of tBuNCO led to the insertion of the isocyanate molecules into the Ti-Nsalan bonds with the formation of [{L*(N(tBu)CO)2}Ti]. Conversely, the reaction of [(H2N2O2)Ti(OiPr)2] with two equiv. of tBuNCO led to the insertion of one isocyanate molecule into a Ti-Nsalan bond with the formation of [{(HN2O2)(N(tBu)CO)}Ti(OiPr)]. Computational studies were performed to gain insight into the reactivity of isocyanates with salan-based Ti(IV) complexes.

Unfolding an Elusive Area-Selective Deposition Process: Atomic Layer Deposition of TiO2 and TiON on SiN vs SiO2.

Area-selective atomic layer deposition (AS-ALD) processes for TiO2 and TiON on SiN as the growth area vs SiO2 as the nongrowth area are demonstrated on patterns created by state-of-the-art 300 mm semiconductor wafer fabrication. The processes consist of an in situ CF4/N2 plasma etching step that has the dual role of removing the SiN native oxide and passivating the SiO2 surface with fluorinated species, thus rendering the latter surface less reactive toward titanium tetrachloride (TiCl4) precursor. Additionally, (dimethylamino)trimethylsilane was employed as a small molecule inhibitor (SMI) to further enhance the selectivity. Virtually perfect selectivity was obtained when combining the deposition process with intermittent CF4/N2 plasma-based back-etching steps, as demonstrated by scanning and transmission electron microscopy inspections. Application-compatible thicknesses of ∼8 and ∼5 nm were obtained for thermal ALD of TiO2 and plasma ALD of TiON.

Pressure Behaviors and Isothermal Kinetics of Magnesiothermic Reduction of Titanium Tetrachloride in a Semi-batch Reactor

Pressure Behaviors and Isothermal Kinetics of Magnesiothermic Reduction of Titanium Tetrachloride in a Semi-batch Reactor