Rani Channamma University is a public university in Belagavi established by the government of Karnataka in 2010 It was created by upgrading Kittur Rani Channamma Post Graduate Centre at Belagavi which was established by the Karnatak University, Dharwad in 1982. The university is recognised by University Grants Commission and accredited by National Assessment and Accreditation Council (NAAC). As of 2021, Rani Channamma University has been awarded "Grade B+" by the NAACThe main aim of this university is to provide an opportunity to develop access to for higher education for students from North Karnataka Region which is deprived of good educational facilities.[citation needed] Rani Channamma University has the main campus, called "Vidyasangama", as its headquarters, on 172 acres of land near Bhutaramanahatti, adjacent to the Pune–Bangalore National Highway 4 about 18 km from Belgavi city. It has been functioning with the jurisdiction of Belgavi, Bijapur and Bagalkot districts..
In this study we have explored the usage of metal complex functionalized naturally occurring smectite clay minerals as solid acid catalyst for the preparation of substituted isoxazol scaffolds. The solid acid catalyst was prepared by modifying Cu(II)-montmorillonite through in-situ complexation of interlayer Cu(II) ions with thiourea by solid state method, and then heated to different temperatures (up to 500 0C). These samples were characterized by XRD, FT-IR, TG/DTA, SEM and UV-DRS techniques, which have confirmed the successful preparation of new series of solid acid catalysts. These catalysts were used for the synthesis of substituted isoxazol scaffolds through the cyclocondensation reaction of ethyl acetoacetate, hydroxylamine hydrochloride with various aldehydes. The catalyst obtained at 300 0C demonstrated the magnificent catalytic performance, affording 96 % yield at mild reaction conditions, due to enhanced acidity which facilitate to transfer the proton during reaction. The increased Br & Oslash;nsted acidity and the ability to control reaction selectivity potentially improved the overall catalytic activity. The reusability and stability of the catalyst were also evaluated. About 75 % yield was obtained even after 4th cycle of catalyst usage. The purity of obtained products were confirmed by 1H NMR, 13C NMR, LCMS and FT-IR analysis. Thus, the developed novel catalyst offers promising strategy for environmentally benign catalytic process.
The development of an efficient and eco-friendly spent lithium-ion batteries (LIBs) recycling strategy is vital for economic and environmental sustainability. This study reports a green, efficient and economic method to convert the cathode portion of spent LIB (LiCoO2) into a high-performance nonprecious Co-oxalate (CoC2O42H2O) electrocatalyst for the oxygen evolution reaction (OER). Here, LiCoO2 collected from the spent LIB cathode was leached in oxalic acid and gallic acid (200:20 mM) mixture at 80 degrees C using a solid-to-liquid ratio of 2 g/L for 1 h. Soon after the dissolution of Co and Li, in situ precipitation of CoC2O4 2H2O was observed in the reaction mixture and soluble Li was precipitated as Li2CO3 and LiHC2O4 H2O when stoichiometric excess of Na2CO3 and oxalic acid were added, respectively. The recovered CoC2O42H2O deposited on stainless steel plate was utilized as an anode for electrochemical OER. It showed an overpotential of 320 mV at 10 mA cm-2, a low Tafel slope (49 mV dec-1) and stable performance over 12 h. Furthermore, the battery grade LiCoO2 was re-synthesized using the stoichiometric amounts of LiHC2O4 H2O and CoC2O4 2H2O. The re-synthesized LiCoO2 showed almost 100% coulombic efficiency with a minimal capacity loss. Thus, we have demonstrated an effective recovery and reuse of cathode material for energy devices.
Two-dimensional mixed metal oxides have been of interest recently, owing to their distinctive crystal structures and multifunctional properties. This article presents a green and sustainable synthesis approach for zinc vanadate (ZNV) nanoparticles (NPs) using chia seed powder by a green solution combustion method. The synthesized ZNV NPs were then employed for the preparation of g-C3N4/Zinc vanadate (ZNVG) nanocomposites (NCs) at 10 %, 20 %, and 30 % of g-C3N4 compositions. XRD, FT-IR, SEM, EDAX, UV-Vis, and PL techniques have been performed to characterize the materials entirely. The size of crystallites calculated through the Debye-Scherrer equation for 10 %, 20 %, and 30 % g-C3N4 doping content are 40 nm, 38 nm, and 37 nm, respectively. UV-Vis spectroscopy shows the redshift in the absorption wavelength and a reduction in the band-gap energy with enhanced light- harvesting features for higher g-C3N4 contents. Photocatalytic investigations have shown that the performance of ZNVG-20 nanocomposite is the optimum; with remarkable degradation efficiencies of 94 % of Rose Bengal and 97 % of Methylene Blue dyes after 180 min. Excellent degradation results were obtained for mixed dyes containing Rose Bengal, Methylene Blue and Methyl Orange and also for environmentally challenging substrates such as rangoli colors. Interestingly, the ZNVG composites also acted as good catalysts in the Knoevenagel condensation reaction, which exhibited up to 92 % efficiency under blue light irradiation. The present findings indicate the versatile potential of ZNVG nanocomposites as photocatalysts and catalysts for addressing environmental and synthetic challenges in a sustainable manner.
Ionic conductivity of La3+ and Mg2+ co-doped ceria, synthesized by auto-combustion method, is investigated here as electrolytes for intermediate-temperature solid oxide fuel cells (IT-SOFCs, operating below 800 degrees C). The prepared nanocrystalline electrolytes, LMDC10 (Ce0.9La0.05Mg0.05O2-delta) and LMDC20 (Ce0.8La0.1Mg0.1O2-delta) have exhibited improved ionic conductivities of 1.31 x 10-2 and 1.39 x 10-1 S cm-1 at 1073 K with reduced activation energies of 0.93 and 0.97 eV, respectively, when compared to conventional electrolytes like yttriastabilized zirconia. The prepared samples are characterized by XRD, Raman spectra, XPS and FESEM which confirmed the formation of single-phasic cubic fluorite structure. Thus, the potential for La3+ and Mg2+ co-doped ceria electrolytes to offer cost-effective alternatives with low sintering temperatures and high performance for ITSOFCs.
Visible-light-driven photocatalysts are predominantly useful for converting solar to hydrogen energy via photocatalytic water-splitting reactions. The heterojunction composite materials have exhibited remarkable advantages for visible-light photocatalytic H-2 evolution. We have successfully synthesized MoO3@f-MWCNT and MoO3@g-C3N4 nanocomposites and characterized them using PXRD, UV-DRS, Raman spectroscopy, XPS, PL, TRPL, FE-SEM, HR-TEM, BET, and photocurrent. The photocatalytic water-splitting efficiency of MoO3@f-MWCNT and MoO3@g-C3N4 was measured under visible light (lambda >= 420 nm) irradiation using TEOA as a sacrificial reagent in DI water and natural seawater. The H-2 evolution rate in DI water for MoO3@f-MWCNT is 2313.56 mu mol g(-)(1) h(-)(1), and for MoO3@g-C3N4 is 2530.35 mu mol g(-1) h(-1) with an apparent quantum efficiency (AQE) of 6.38 and 6.93%, respectively. In natural seawater, the H-2 evolution rate is 2632.20 and 2845.06 mu mol g(-1) h(-1), with an AQE of 7.21 and 7.77%, respectively. The rate of H-2 evolution slightly increased in natural seawater than DI water. The Tafel slope values for MoO3@g-C3N4 and MoO3@f-MWCNT are 59 and 92 mV dec(-1), respectively. The lowest Tafel value of MoO3@g-C3N4 exhibited a faster rate of reaction. Thus, the surface interaction between the MoO3 and the porous g-C3N4 materials may create synergistic effects, which facilitate electron transport at the interface and significantly boost the photocatalytic activity. Thus, MoO3@g-C3N4 is a promising photocatalyst for renewable energy production.
