http://ore.immt.res.in/handle/2018/4 Fri, 03 Jul 2026 23:39:04 GMT 2026-07-03T23:39:04Z http://ore.immt.res.in/handle/2018/3974 Recent advances in SnTe-based thermoelectric materials: Synthesis, band engineering, and performance optimization Behera, A.; Velu, N. K. Tin telluride (SnTe) has gained renewed attention as a sustainable alternative to lead-based thermoelectrics for mid-temperature waste-heat recovery. Its rock-salt structure, high carrier mobility, and suitable band structure make it an attractive candidate; however, the high intrinsic hole concentration and relatively high lattice thermal conductivity limit its figure of merit (ZT). In recent years, significant progress has been made through strategies such as aliovalent doping, alloying, band convergence, and microstructural engineering to improve its thermoelectric efficiency. This review summarizes key developments in the synthesis and optimization of SnTe-based materials prepared by melt growth, mechanical alloying, solution processing, and spark plasma sintering. Emphasis is placed on the correlation between synthesis conditions, resulting defect chemistry, and their influence on carrier concentration, Seebeck coefficient, and lattice thermal conductivity. Recent advances, including multi-doping, nanoscale precipitate formation, and defect-controlled phonon scattering, are critically examined to highlight their impact on transport properties. The review concludes with an outlook on scalable synthesis, long-term stability, and future opportunities for achieving high-performance, lead-free SnTe thermoelectrics suitable for practical energy-harvesting applications. Thu, 01 Jan 2026 00:00:00 GMT http://ore.immt.res.in/handle/2018/3974 2026-01-01T00:00:00Z http://ore.immt.res.in/handle/2018/3973 Enhanced Piezoelectric and Mechanical Performance in Electrospun PVDF-HFP/BCZT Nanofiber Composites for Energy Harvesting Sahoo, S.; Nayak, B.; Anwar, S.; Mohapatra, M.; Anwar, S. Highly polarized electrospun PVDF-HFP/BCZT nanofiber composite films were successfully fabricated and systematically investigated for their dielectric, ferroelectric, piezoelectric, mechanical, and energy-harvesting performance. The electrospinning fabrication process, along with the incorporation of Ba0.8 5Ca0.1 5Zr0.1Ti0.9O3 (BCZT) nanoparticles, significantly enhanced beta-phase content along with the interfacial polarization within the polymer matrix. Optimal performance was achieved at 30 wt % ceramic loading. The optimized composite exhibited a high dielectric constant, improved remnant polarization, low leakage current density (similar to 10-6 A/cm2 at 350 kV/cm), and superior energy storage performance, with a recoverable energy density of 26.41 mJ/cm3 and an efficiency of 52.47%. Nanoindentation analysis revealed enhanced mechanical stability, with an elastic modulus of 9.26 +/- 0.2 GPa, enabling efficient mechanical stress transfer for piezoelectric applications. Piezo-response force microscopy confirmed enhanced electromechanical coupling, with the effective piezoelectric coefficient (d3 3*) improving from similar to 38.3 to similar to 161 pm/V. The piezoelectric energy harvester based on the optimized nanofiber film delivered an output voltage of 68.4 V and a power density of 406.4 mu W/cm3 under cyclic loading, demonstrating excellent durability and real-world applicability. These results establish PVDF-HFP/BCZT nanofiber composites as promising candidates for flexible, self-powered energy-harvesting and sensing systems. Thu, 01 Jan 2026 00:00:00 GMT http://ore.immt.res.in/handle/2018/3973 2026-01-01T00:00:00Z http://ore.immt.res.in/handle/2018/3972 Industrial cashew press cake waste-assisted co-gasification of low-rank coal towards hydrogen-enriched syngas production Saini, R.; Rao, D. S.; Pradhan, N. Cashew press cake (CPC) waste, generated from an industrial unit, was utilized in conjunction with a high-ash coal to evaluate its energy potential values via a co-gasification route in a fluidized-bed system under air-steam conditions. A detailed experimental investigation was accomplished at varying equivalence ratios from 0.15 to 0.30 by manipulating the air-flow rate to the gasifier system at a constant reactor operating temperature of about 800 degrees C and pressure of about 1-2 bar. For the coal and CPC blended sample, an experimentally determined optimum equivalence ratio of 0.25 showed significant improvement in the gasifier performance parameters, with cold gas efficiency and carbon conversion efficiency values reaching almost 91% and 79%, respectively, in comparison to the coal-only sample. Hydrogen concentration also augmented from around 17 vol% to 39 vol % in the air-steam conditions when almost 20 wt% of coal was replaced with CPC feed having potential catalytic properties towards gasification. Thu, 01 Jan 2026 00:00:00 GMT http://ore.immt.res.in/handle/2018/3972 2026-01-01T00:00:00Z http://ore.immt.res.in/handle/2018/3971 The novel application of the ionic liquid Tetrabutylphosphonium-O, O-diethyl phosphorodithioate as a collector in chalcopyrite Flotation: A greener replacement of xanthates Swain, P.; Dash, B.; Rath, S. S. This communication reports the novel application of an ionic liquid (IL), Tetrabutylphosphonium-O, Odiethyl phosphorodithioate (TPBDBT), as a greener alternative to xanthate-based collectors for chalcopyrite flotation. Flotation studies of a low-grade Indian chalcopyrite ore (similar to 0.7% Cu) were undertaken to evaluate the collecting ability of TPBDBT. Under optimal conditions (25 g/t collector, pH 7.40, 100 g/t depressant), the IL-based collector could generate a concentrate having about 26.18% Cu at 85.81% recovery, outplaying the conventional collector, Sodium Isopropyl Xanthate (SIPX), which could upgrade the Cu grade to about 23%. Characterization studies comprising zeta potential measurements, Fourier Transform Infrared (FT-IR) spectroscopy, Ultraviolet-visible spectroscopy (UV-Vis), UV-Vis Diffuse Reflectance Spectroscopy (UV-Vis DRS) and X-ray Photoelectron Spectroscopy (XPS) studies revealed stronger bonding and better adsorption of TBPDBT on chalcopyrite. Besides, Molecular Dynamics (MD) simulations confirmed that TBPDBT induces stronger hydrophobicity on the chalcopyrite surface compared to SIPX, thereby rationalizing the superior flotation efficiency of the former. Collective experimental and theoretical studies proved TBPDBT as a sustainable reagent, offering a reduced chemical footprint. (c) 2026 Published by Elsevier B.V. on behalf of The Society of Powder Technology Japan. All rights are reserved, including those for text and data mining, AI training, and similar technologies. Thu, 01 Jan 2026 00:00:00 GMT http://ore.immt.res.in/handle/2018/3971 2026-01-01T00:00:00Z