Performance Analysis of CFRP Composite Strips Confined RC Columns under Axial Compression

In an attempt to mitigate the high cost of FRP composite strengthening, an experimental investigation was carried out that sought to achieve efficient and most favorable FRP strengthening using CFRP composite strips. 50 mm wide CFRP composite strips were used in two different spacings (20 mm and 40 mm) to confine columns. The test results of the column confined with smaller spacing (20 mm) showed significant restraint of axial deformation of the column and enhanced the strength capacity to a maximum of 99.20% compared to that of reference column. In contrast, the column confined by strips with larger spacing (40 mm) failed by crushing of concrete alone, which occurred even before the CFRP strips reached their ultimate strain. In addition, the embodied energy that exists in the CFRP strips could not be utilized effectively. The stress and strength enhancement ratio of this present study was compared with the previous research that has been conducted on columns confined with full wrapping. From the obtained results, it is recommended that CFRP strips with a spacing of 20 mm be used to improve the strength capacity of the RC column; in addition, this wrapping technique provides economic benefits compared to a column confined with full wrapping

All inorganic based Nd0.9Mn0.1FeO3 perovskite for Li-ion battery application: Synthesis, structural and morphological investigation

Mn doped perovskite structured Nd0.9Mn0.1FeO3 nanoparticles have been successfully prepared using hydrothermal method in aqueous medium. The structural and morphological properties were investigated using XRD, SEM, FE-SEM, and TGA. After establishing the structure and morphology of the compound, thorough investigation into elemental composition with the use of EDX and XPS were carried out. Microstructure arrangement was done with the use of HR-TEM while the BET analysis confirmed the high surface area of the nanoparticles. The structural information was further investigated by AFM. The average particle size of Nd0.9Mn0.1FeO3 nanoparticles increased from 60 to 100 nm with increasing annealing temperature from 500 to 1000 �C, respectively. The structural characterizations confirmed the perovskite nanoparticles to be crystalline orthorhombic structure. Moreover, the new material was explored as anode material for Li-ion battery. The galvanostatic cycling measurement shows that the cells possess reversible specific capacity of 763 mAhg�1 at a current density of 0.5 A g�1 after 100 cycles. The charging and discharging profiles shows that the compound of this kind could be future candidate for electrode material

Integration of phenylammoniumiodide (PAI) as a surface coating molecule towards ambient stable MAPbI3 perovskite for solar cell application

In the present work, different hybrid perovskites were synthesized by gradual concentration variation of larger cation of phenylammoniumiodide (PAI) and methylammoniumiodide (MAI) in PbI2 solution with the aim of improving the stability of MAPbI3 film and photovoltaic efficiency. To understand the properties of perovskite like structural, optical, thermal, morphological and chemical state, extensive characterizations such as XRD, UV–visible spectroscopy, FE-SEM, SEM, EDX and XPS were performed. The role of PAI was investigated further with the use of DFT studies. The DFT results confirmed that the PAI was passivated on the surface of MAPbI3 with most stable arrangement. The stable arrangement revealed the formation of ᴫ-ᴫ interactions within the phenyl rings, which shielded the MAI crystals and thereby resulted in enhanced stability of the perovskites. Highly protected perovskite consequently yielded high- performance solar cell device with enhanced stability under 60% humidity, high temperature exposure and longer time stability even when directly exposed to normal room temperature. The new investigation of capping techniques with the use of bigger organic molecules, high performance solar cell with low device costs could emerge. This could lead to unprecedented rapid progress on power conversion efficiency (PCE). Thus, more stable organic-inorganic hybrid perovskites could be developed for future applications

Silver decorated CeO2 nanoparticles for rapid photocatalytic degradation of textile rose bengal dye

High quality silver (Ag) decorated CeO2 nanoparticles were prepared by a facile one-step chemical method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), High resolution transmission electron microscopy (HR-TEM), fourier transform infrared spectrometer (FT-IR), electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), UV–Visible absorption (UV–Vis), photoluminescence (PL) and thermogravimetric analysis. The decoration of Ag on CeO2 surface was confirmed by XRD, EPR and HR-TEM analysis. Harmful textile pollutant Rose Bengal dye was degraded under sunlight using the novel Ag decorated CeO2 catalyst. It was found that great enhancement of the degradation efficiency for Ag/CeO2 compared to pure CeO2, it can be ascribed mainly due to decrease in its band gap and charge carrier recombination rate. The Ag/CeO2 sample exhibited an efficient photocatalytic characteristic for degrading RB under visible light irradiation with a high degradation rate of 96% after 3 h. With the help of various characterizations, a possible degradation mechanism has been proposed which shows the effect of generation of oxygen vacancies owing to the decoration of Ag on the CeO2 surface. © 2021, The Author(s)

A Facile Synthesis of Sn-Doped CeO2 Nanoparticles: High Performance Electrochemical Nitrite Sensing Application

Development of novel electrode materials for sensing water pollutant like nitrite, nitrate, paramedical pollutants and fertilizers is a more promising research area in electrochemical sensor field. Various pure as well as doped metal oxides were used as electrodes for sensing the water pollutants but, deficits in stability, reproducibility and real time analysis. In the present work, a promising Sn-doped CeO2 based sensor was fabricated for sensing nitrite in water. A selective concentration of Sn (5%) doped CeO2 nanoparticles were synthesized by facile chemical precipitation method. The structural, optical and morphological information were studied using various techniques. The morphological of the sample was revealed an agglomerated with spherical nanoparticles with size of 8.5 nm. The synergistic effect of Sn-CeO2/GCE improves the electrochemical behavior of nitrite on the modified surface. Sn-doped CeO2 nanoparticles has a better surface property and provides a more fine-grained media to facilitate electron transfer during the reaction between analyte and electrode. The Sn-CeO2/GCE electrode possesses excellent electrocatalytic oxidation of nitrite (NO2–) which was investigated by cyclic voltammetry (CV) and amperometry techniques. The remarkable sensitivities of nitrite were found that 245.4 µA cm−2 mM−1 and 89.53 µA cm−2 mM−1 with R2 = 0.999 and RSD of ∼ 6%. Similarly, the limit of detection (LOD) towards nitrite ion sensing was found to be 16 nM. The real time application of Sn-CeO2/GCE sensor was demonstrated by the detection of nitrite present in environmental water samples with excellent recoveries. Hence, Sn-doped CeO2 modified electrode also demonstrates good reproducibility, long time stability, and excellent selectivity properties. Thus, a developed electrochemical sensor possesses a novel promise for the construction of simple and sensitive nitrite analytical stage. © 2021 Elsevier B.V.The authors thank Chancellor, President and Vice Chancellor, Sathyabama Institute of Science and Technology, Chennai for the support and encouragement. The author R. Jothi Ramalingam thank for the financial support by the Researchers Supporting Project Number (RSP-2021/354), King Saud University, Riyadh, Saudi Arabia

Structural, morphological, optical and electrochemical characterization of Ag2O/ZnO and ZnO/Ag2O nanocomposites

In this paper, well-crystalline Ag2O/ZnO and ZnO/Ag2O nanocomposites were prepared by a facile chemical method. Structural, morphological and optical properties of the nanocomposite were studied using various advanced characterization techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), UV-Visible (UV-Vis) and photoluminescence (PL) spectroscopy. The Ag2O and ZnO were clearly identified in the composite from SEM and TEM. Significant shifting observed in the both UV-Vis and PL spectroscopy. In addition, electrocatalytic activity of the Ag2O/ZnO and ZnO/Ag2O nanocomposites studied by an electrochemical workstation. The ZnO/Ag2O nanocomposites showed better optical and electrochemical properties due to decorating the low-band gap Ag2O on the surface of hexagonal structure ZnO nanoparticles. © 2022, S.C. Virtual Company of Phisics S.R.L. All rights reserved.RSP-2021/293; King Saud University, KSU: 40/is2Dr. G. Murugadoss would like to acknowledge to the management of Sathyabama Institute of Science and Technology, Chennai, Tamilnadu, India for provided lap facilities. The author (Wahidah H. Al-Qahtani) thank and This work was funded by the Researchers Supporting Project Number (RSP-2021/293) King Saud University, Riyadh, Saudi Arabia. One of author (Manavalan Rajesh Kumar) thanks to the contract no. 40/is2

Tuning visible emission of core-shell nanostructure by exchange the inner and outer layer

Herein, we report that synthesis of ZnS/Bi2S3 and Bi2S3/ZnS core-shell nanostructure prepared by ‘one-pot’ chemical method. We have studied the effect of structural, morphological, optical and thermal properties by exchanging the inner and outer layer of core-shell nanoparticles. The samples were studied using various characterization techniques such as XRD, TEM, FTIR, UV–Vis, Photoluminescence and TG-DTA. The XRD and TEM results demonstrated that the synthesized core-shell nanoparticles were in cubic (ZnS)-orthorhombic (Bi2S3) mixed crystal structures with a diameter of 18.6 nm and 16.3 nm with extremely monodispersing. The obtained result provides a new and simple route for synthesis of sulfide-based core-shell nanoparticles with high crystal quality. © 2021, S.C. Virtual Company of Phisics S.R.L. All rights reserved.Sathyabama Institute of Science and Technology, ChennaiKing Saud University, KSUThe authors acknowledge the Researchers Supporting Project Number (RSP-2021/354) King Saud University, for financial supports, Riyadh, Saudi Arabia. The author Dr. G. Murugadoss thanks the Chancellor, President, and Vice Chancellor, Sathyabama Institute of Science and Technology, Chennai for the support and encouragement