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This study focuses on the preparation and characterization of Mg‐Ni co‐doped TiO2 and its application in the degradation of the pharmaceutical ofloxacin (OFX) under solar irradiation. A wet impregnation method was used to prepare Mg‐Ni co‐doped TiO2. Characterization, optimization, and kinetic studies revealed that the doped TiO2 material is effective in degrading OFX, with potential applications in water treatment or environmental remediation processes. Ultraviolet diffuse reflectance spectroscopy indicated that the band gap of TiO2 was reduced due to doping with Mg and Ni. A reduced band gap can enhance the material's photocatalytic properties, which is important for its application in solar‐driven degradation processes. The catalyst dose and OFX concentration for the degradation process were optimized. A catalyst dose of 2 g L−1 and an OFX solution with a concentration of 40 ppm, maintained at pH 5, resulted in the highest degradation efficiency. The degradation process followed first‐order kinetics, suggesting that the rate of degradation increased with increasing doping. [ABSTRACT FROM AUTHOR]

Several drugs have sparked interest as potential COVID-19 treatment options. Doxycycline (DOX) has been widely used with other potential agents to reduce COVID-19-induced inflammation. DOX and OFLX, both well-known antimicrobial and anti-inflammatory drugs, were chosen as model pollutants. Fe, Cu-codoped TiO2-SiO2 was synthesised as a novel photocatalyst active under sunlight irradiation to treat model pollutants. The synthesised catalyst samples were meticulously characterised using various techniques to evaluate their morphological, optical, and structural properties. The results of BET analysis showed that the TSFC1 sample has a large specific surface area of 288 m² g-1. Maximum degradation of DOX and OFLX (about 98%) was achieved with the TSFC1 catalyst. The photocatalytic reusability was investigated for up to seven successive cycles, and the composite particles maintained their high photodegradation activity for DOX and OFLX. TFSC1 composite, in particular, demonstrated high catalytic activity as well as excellent recovery potential, and its combination with solar light, silica, and dopants can be introduced as a promising strategy for efficiently destroying both DOX and OFLX antibiotics. This study highlights the feasibility of hybridising doped dual semiconductor nanostructures in implementing solar light-powered pharmaceutical wastewater degradation. [ABSTRACT FROM AUTHOR]

Photocatalysis is an extraordinary and vastly researched topic; there is a need to find new ways to support producing composite materials that are cost-effective, efficient and have a low environmental impact. The investigation was undertaken on syn TiO2 by depositing it on silica. The results elucidate the positive effect on photocatalysis activity and the macroscopic structure on which the TiO2 is formed. For the analysis of photocatalyst, various characterisation measurements were undertaken, such as XRD, FTIR, DRS, FESEM, TEM, RS, and BET. The accumulated TiO2 onto the surface of SiO2 stabilised its transformation of the phase from anatase to rutile, resulting in decreased particle size and enhancing its photocatalytic activity under UV irradiation. The concentration of OH• radicals was determined using terephthalic acid as a probe molecule to determine its role in the photocatalytic degradation of antihistamine. The results of BET analysis showed that the syn TiO2-SiO2 sample has a large specific surface area of 192.6 m2 g−1. Maximum degradation of cetirizine (about 97%) was achieved with 80% TiO2-20% SiO2 (TS-4). Recyclability test confirmed that 80% TiO2-20% SiO2 sample was stable up to six cycles. [ABSTRACT FROM AUTHOR]

TiO2-SiO2 mixed oxides in ratios between 20:80 and 80:20 have been prepared using a sol-gel method. To make full use of catalysis, optimization conditions such as SiO2 content, solution pH, and catalyst loading were investigated. The photocatalysts were characterized spectroscopically as nanoparticles of small crystallite size. Their efficiency for UV-A light induced photocatalytic degradation of amoxicillin and ofloxacin was evaluated, with 80% TiO2-20% SiO2 being the most active, resulting in complete mineralization and non-toxicity. The catalyst shows some recyclability up to the seventh cycle. [ABSTRACT FROM AUTHOR]

Formaldehyde is one of the vital chemicals produced by industries, transports, and domestic products. Formaldehyde emissions adversely affect human health and it is well known for causing irritation and nasal tumors. The major aim of the modern indoor formaldehyde control study is in view of energy capacity, product selectivity, security, and durability for efficient removal of formaldehyde. The two important methods to control this harmful chemical in the indoor environments are photocatalytic oxidation and catalytic oxidation with noble metals and transition metal oxides. By harmonizing different traditional photocatalytic and catalytic oxidation technologies that have been evolved already, here we give a review of previously developed efforts to degrade indoor formaldehyde. The major concern in this article is based on getting the degradation of formaldehyde at ambient temperature. In this article, different aspects of these two methods with their merits and demerits are discussed. The possible effects of operating parameters like preparation methods, support, the effect of light intensity in photocatalytic oxidation, relative humidity, etc. have been discussed comprehensively. [ABSTRACT FROM AUTHOR]

The present work deals with the modeling and optimization of photocatalytic degradation (UV/TiO2) of aqueous solution of Acid Red 114 (AR114) dye using Artificial Neural Networks (ANN) and RSM. Photocatalytic treatment of AR114 has been executed using suspension TiO2catalyst for commercial applications exposed to ultraviolet irradiation in a shallow pond reactor. ANN optimization has been applied to for predicting the behavior of photocatalysis. The input parameters used for analysis of aqueous dye solution are - TiO2 dose, pH of the dye solution, initial dye concentration, UV light intensity, time and area/volume, and time whereas the outputs are evaluated in form of degradation and decolorization efficiency of AR114. The outcomes of ANN optimization have been experimentally validated. Results achieved establish ANN modeling as a good predictive model. Parameteric optimization using multi-parameter optimization has been employed with desirability function approach. Results obtained from RSM are in line as per the results of ANN modeling as well as experimental. First order kinetics is use to effectively express degradation and decolorization of AR114 dyes. Total organic carbon (TOC) removal and GC-MS study of the dye shows the total mineralization and formation of non-toxic intermediate products. [ABSTRACT FROM AUTHOR]

TiO2 nanoparticles have been doped and co-doped with two metal ions (Fe and Cu) via the wet impregnation method. The doped and co-doped TiO2 have been characterized by standard analytical techniques like XRD, Raman spectra, FTIR, UV-Vis DRS, FESEM, and TEM. Powder XRD technique reveals that the modified catalyst majorly contains an anatase phase with the existence of metal ions in the lattice of TiO2. Raman and UV-Vis absorption spectra of the doped and co-doped catalyst show a λmax shift towards the longer wavelength region with an increase in metal ion concentration from 1 to 2%. FTIR patterns show the stretching and vibration patterns of the hydroxyl radicals present in the nanoparticles. FESEM images reveal that the average particle size of the modified TiO2 lies between 18 and 24 nm due to the asymmetric shape of nano crystallite TiO2. TEM images suggest that the doping and co-doping of metal ions do not leave any change in the shape of the nanoparticles. Furthermore, anti-cancerous activities of TiO2 nanoparticles and Fe, Cu doped and co-doped particles have been studied, revealing the toxicity of Cu ions doped TiO2 on cervical cancer cell line. [ABSTRACT FROM AUTHOR]

TiO2 nanoparticles have been doped and co-doped with two metal ions (Fe and Cu) via the wet impregnation method. The doped and co-doped TiO2 have been characterized by standard analytical techniques like XRD, Raman spectra, FTIR, UV-Vis DRS, FESEM, and TEM. Powder XRD technique reveals that the modified catalyst majorly contains an anatase phase with the existence of metal ions in the lattice of TiO2. Raman and UV-Vis absorption spectra of the doped and co-doped catalyst show a λmax shift towards the longer wavelength region with an increase in metal ion concentration from 1 to 2%. FTIR patterns show the stretching and vibration patterns of the hydroxyl radicals present in the nanoparticles. FESEM images reveal that the average particle size of the modified TiO2 lies between 18 and 24 nm due to the asymmetric shape of nano crystallite TiO2. TEM images suggest that the doping and co-doping of metal ions do not leave any change in the shape of the nanoparticles. Furthermore, anti-cancerous activities of TiO2 nanoparticles and Fe, Cu doped and co-doped particles have been studied, revealing the toxicity of Cu ions doped TiO2 on cervical cancer cell line. [ABSTRACT FROM AUTHOR]

Photocatalytic treatment of a binary dye mixture (Acid Blue 113 (AB113) and Acid Red 114 (AR114)) has been done in a slurry pond reactor using TiO2 as a photocatalyst with UV light irradiation (UV-C). Two different methods, namely multivariate calibration and first order derivative spectrophotometric were used to quantify each dye separately in binary dye solutions. The behavior of the photocatalytic degradation of a binary dye mixture was predicted using an artificial neural network (ANN) model. Five process parameters (initial concentration of AB113 dye, initial concentration of AR114 dye, TiO2 dose, initial pH of the dye mixture and time were used as inputs and decolorization efficiency of AB113 and AR114 were used as output of the ANN. The parametric optimization has been done by the multiresponse optimization with desirability function methodology. Optimization by Central Composite Design (CCD) effectively handles the relations among optimizing process variables and its prediction concurred well with the experimental run and artificial neural network (ANN) model. The reaction kinetic rates of decolorization of both dyes (AB113 and AR114) were found to be first order. Total organic carbon (TOC) removal and possible reaction pathway show the total mineralization of both dyes in binary dye mixture. [ABSTRACT FROM AUTHOR]

Photocatalytic treatment of Reactive Black 5 dye wastewater was carried out using suspension of commercially available TiO2catalyst under ultraviolet irradiation in a shallow pond reactor. An artificial neural network (ANN) model was developed to predict the behavior of the process. Six operational parameters (TiO2dose, initial dye concentration, pH of the dye solution, area to volume ratio, UV light intensity, and time) were employed as input and decolorization and degradation efficiencies were employed as output of the network. The outcomes have been validated experimentally indicating that the ANN provided reasonable predictive performance. The parameteric optimization was done, using multiresponse optimization with desirability function approach, to simultaneously maximize the decolorization and degradation efficiency. Optimization by Box–Behnken design effectively copes with interaction between optimizing variables and its prediction agreed well with the results of ANN model and experimental run. The decolorization and degradation follows the pseudo-first-order kinetics. [ABSTRACT FROM PUBLISHER]

We propose injection-locked clocking (ILC) to combat deteriorating clock skew and jitter, and reduce power consumption in high-performance microprocessors. In the new clocking scheme, injection-locked oscillators are used as local clock receivers. Compared to conventional clocking with buffered trees or grids, ILC can achieve better power efficiency, lower jitter, and much simpler skew compensation thanks to its built-in deskewing capability. Unlike other alternatives, ILC is fully compatible with conventional clock distribution networks. In this paper, a quantitative study based on circuit and microarchitectural-level simulations is performed. Alpha21264 is used as the baseline processor, and is scaled to 0.13 μm and 3 GHz. Simulations show 20- and 23-ps jitter reduction, 10.1% and 17% power savings in two ILC configurations. A test chip distributing 5-GHz clock is implemented in a standard 0.18-μm CMOS technology and achieved excellent jitter performance and a deskew range up to 80 ps. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes (AOPs) including heterogeneous photocatalysis has proven as one of the best technique for waste-water treatment. Photocatalytic process using semiconductor like TiO2 based heterogeneous photocatalysis is a promising method for the treatment of toxic pollutants. In the present study, visible-light photoactive cobalt and nitrogen co-doped TiO2 nanoparticles were synthesized via wet impregnation method. The photocatalysts were characterized using X-ray diffraction (XRD), Raman Spectra, Fourier Transform Infrared (FTIR) Spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscope (TEM), UV-vis spectrophotometer and X-ray photoelectron spectrophotometer (XPS). The photocatalytic activitiy of prepared (N, Co)-codoped TiO2 on the mineralization of Bisphenol-A (BPA) under visible light irradiation was studied and the results were compared to commercial TiO2 (Degussa P25). The results demonstrated that 1.5% Co and 0.5% N - codoped TiO2 samples revealed higher activity than commercial TiO2. Total organic carbon (TOC) removal was observed to be 97%, which indicate the complete mineralization of BPA. GC-MS analysis was carried to find out the possible intermediates formed and reaction pathway. [ABSTRACT FROM AUTHOR]