http://ore.immt.res.in:80 The ORE digital repository system captures, stores, indexes, preserves, and distributes digital research material. 2026-04-20T10:01:45Z http://ore.immt.res.in/handle/2018/3940 Quinoxaline-Functionalized Palladium(II)-NHC Electrocatalysts: Soaring Efficiency in a Low-Overpotential Hydrogen Evolution Reaction (HER) Sahu, P.; Hota, A.; Jana, N. C.; Tripathy, B. C.; Vener, M. V.; Dinda, J. In the pursuit of meeting the growing demand for a green hydrogen economy, the electrochemical hydrogen evolution reaction (HER) stands out as one of the most efficient and sustainable pathways. In this context, the rational design of effective electrocatalysts based on metal-N-heterocyclic carbene (NHC) complexes holds great promise, offering a highly versatile and robust approach. Proceeding in this direction, herein, we assessed the electrocatalytic performance of three Pd(II) complexes (Pd1, Pd2, and Pd3) based on quinoxaline-wingtip NHCs toward the hydrogen evolution reaction (HER) in acidic medium (0.5 M H2SO4). All of the complexes were synthesized via the transmetalation route and thoroughly characterized using various spectroscopic and analytical techniques, including single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), and high-resolution mass spectra (HR-MS) analyses. Single-crystal X-ray crystallography reveals that variation of the imidazole N-substituent influences the coordination behavior of Pd(II), resulting in mononuclear and dinuclear complexes. Among the complex fabricated CC electrodes, Pd1 exhibited the best performance, affording a quite low overpotential of only -5 mV vs reversible hydrogen electrode (RHE) to deliver a current density of -10 mA/cm2 with a Tafel slope of 96 mV/dec, followed by Pd3 and Pd2. Pd1 also demonstrated excellent long-term operational stability over 24-25 h. The promising HER activity of Pd1 can be attributed to the presence of Cl & centerdot;& centerdot;& centerdot;pi interactions and rare-type Cl & centerdot;& centerdot;& centerdot;Cl interactions, which facilitate the development of two-dimensional (2D) polymeric network-like structures, supported by density functional theory (DFT) studies and Hirshfeld surface analysis. Hence, the present study validated the successful application of rationally designed Pd(II)-NHC complexes as promising HER electrocatalysts. 2026-01-01T00:00:00Z http://ore.immt.res.in/handle/2018/3939 Unleashing Sodium-Sulfur Battery Performance With Atomically Dispersed Single Atom Catalysts Maiti, S.; Curnan, M. T.; Almusleh, N.; Subhalaxmi, S.; Shin, D.; Narayan, R.; Maiti, K.; Hur, J. To design devices with formidable theoretical energy density while employing abundant and inexpensive materials, c (RT Na-S) batteries serve as formidable candidates. However, widespread adaptation of RT Na-S batteries is impeded by numerous salient concerns, including slow redox kinetics at S cathodes and the shuttle effect of solvated sodium polysulfide intermediates (NaPSs). These drawbacks limit industrial implementation of such batteries by diminishing Coulombic efficiency, rapidly decaying capacity, and inhibiting stable cycling. Nevertheless, single atom catalysts (SACs) are viable candidates for alleviating these problems, given their distinctive active sites, tunable electronic structures, and idealized atomic utilization. These properties grant SACs capabilities spanning the acceleration of electrochemical kinetics, the anchoring of intermediate species, and unmitigated NaPS conversion. Herein, we first investigate how morphological features and well-characterized atomic structures are linked to catalytic performance enhancement in RT Na-S batteries, describing how SACs impact redox kinetics and reactive efficiency toward developing battery technologies. Subsequently, we expound upon how theoretical density functional theory (DFT) simulations resolve the adsorbate-surface configurations and electronic structures respectively responsible for the fundamental reaction mechanisms and charge transfer processes undergirding battery electrochemical performance. Lastly, this review encapsulates current challenges to Na-S SAC research, proposing avenues to guide future work. 2026-01-01T00:00:00Z http://ore.immt.res.in/handle/2018/3938 DNA nanomaterials loaded with curcumin and antimiRNA inhibits cell proliferation: A biophysical and cellular study Kar, A.; Sundaray, K.; Subudhi, U. Curcumin (Cur) is a class of flavonoids isolated from turmeric (Zingiberaceae family), which has numerous biological applications, including antimicrobial, anti-inflammatory, antioxidant and anticancer effects. Since Cur has less solubility in aqueous solvents, and poor cellular permeability, a new drug delivery strategy is desired to enhance the therapeutic potential of Cur. In the current study, we synthesized branched DNA (bDNA) and tetrahedron DNA (tDNA) nanomaterials with antimiRs that binds to Cur through electrostatic interaction for promoting drug delivery. Meanwhile, Cur-bound DNA nanostructures exhibiting hypochromic effect in absorbance and decreased fluorescence intensity. Dye displacement studies reveal the binding of Cur to DNA nanostructures by replacing DAPI, Hoechst, and Ethidium bromide. Furthermore, conformation of DNA nanostructures was unaltered in the presence of Cur in CD spectroscopic studies. FTIR spectra determine the structural bonding between Cur and DNA nanostructures. Moreover, the cell proliferation activity was significantly decreased in the presence of complexes, which confirms the increased tumor suppression activity of Cur-loaded antimiR-DNA nanomaterials. Cur exhibited spontaneous and enthalpy-driven binding to bDNA and tDNA nanostructures, where structural architecture influenced the interaction strength. Thus, the finding can be explored to design novel DNA nanostructures containing multiple antimiRs which can synergistically downregulate multiple oncogenic miRNAs and applied for cancer therapeutics. 2026-01-01T00:00:00Z http://ore.immt.res.in/handle/2018/3936 Electrocatalytic Oxygen Reduction Reaction Using a Water-Stable Ni-Based Coordination Polymer with Two-Dimensional Honeycomb Architecture Sarkar, S.; Nayak, B.; Purohit, S. V.; Singha, D. K.; Dash, B.; Laha, S.; Jena, B. K.; Mahata, P. A new Ni(III)-based metal-organic coordination polymer (MOCP) of formula [Ni(4,4 '-IPDPA)1.5(H2O)3]& centerdot;6H2O (4,4 '-IPDPA = 4,4 '-isopropylidenediphenoxyacetate), 1, has been synthesized at ambient temperature using the slow layer diffusion method. The framework of compound 1 was obtained through single-crystal X-ray diffraction (SCXRD). It was comprehensively analyzed by various methods, including powder X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), ultraviolet-visible (UV-vis) spectroscopy, luminescence spectroscopy, Brunauer-Emmett-Teller (BET) analysis, and X-ray photoelectron spectroscopy (XPS). Compound 1 shows promising electrocatalytic activity for the oxygen reduction reaction (ORR) in alkaline conditions. With a nearly four-electron reduction mechanism and a half-wave potential of 0.72 V versus a reversible hydrogen electrode (RHE), compound 1 exhibits remarkable ORR performance. The compound 1 most intriguingly showed good long-term stability. In addition to the presence of accessible pores within the framework, the emergence of the reduced Ni(II) moiety from Ni(III) during cathodic polarization is believed to be responsible for the high level of activity. Compound 1 also demonstrated exceptional resistance toward methanol poisoning during the ORR activity. Moreover, the density functional theory (DFT) analysis suggests that the as-prepared Ni3+-ion-based MOCP follows the four-electron-guided ORR pathway with the formation of *O intermediate as the potential-determining step (PDS). 2026-01-01T00:00:00Z