@article { ISI:000284238000028, title = {Rapid generation of hierarchical nanoarchitectures of CdS via facile microwave assisted hydrothermal/semi-solvothermal route}, journal = {International Journal of Nanotechnology}, volume = {7}, number = {9-12, SI}, year = {2010}, month = {DEC}, pages = {1120-1130}, publisher = {INDERSCIENCE ENTERPRISES LTD}, address = {WORLD TRADE CENTER BLDG, 29 ROUTE DE PRE-BOIS, CASE POSTALE 896, CH-1215 GENEVA, SWITZERLAND}, abstract = {

1-D nanorod bundles as well as sea urchin and starfish like hierarchical morphological nanoarchitectures of CdS have been synthesised using a facile microwave assisted hydrothermal/semi-solvothermal technique. Observation of interesting regular/irregular pine-tree like secondary growth over these hierarchical nanoarchitectures is an important aspect of this work. Cadmium acetate and thiourea were used as precursor materials and were dissolved in solution containing mixture of diethylene triamine (DETA) and deionised water (DIW) in different volume ratios prior to subjecting the resultant solution to microwave radiation of 300 W at a reaction time of 10 min and temperature of 140 degrees C. XRD revealed formation of hexagonal CdS with strong (002) preferred orientation (c-axis orientation). Morphology dependent optical properties are studied using room temperature photoluminescence spectroscopy. We feel such secondary growth will be highly favourable in determining the non-linear properties of optoelectronic devices fabricated using such novel hierarchical nanoarchitectures.

}, keywords = {CdS, hierarchical nanoarchitectures, Microwave, Nanorods, secondary growth, solvothermal synthesis}, issn = {1475-7435}, author = {Shinde, Manish D. and Pawar, Amol U. and Sreeja, V. and Rane, Sunit and Potdar, Hari S. and Amalnerkar, Dinesh P.} } @article {43882, title = {Activity tuning of cobalt ferrite nanoparticles anchored on N-doped reduced graphene oxide as a potential oxygen reduction electrocatalyst by Zn substitution in the spinel matrix}, journal = {Chemistry Select}, volume = {2}, year = {2017}, month = {SEP}, pages = {7845-7853}, type = {Article}, abstract = {

Development of highly efficient and durable ORR catalysts by using non-platinum group metals (such as Co, Fe, Mn, and Zn) is a challenging task in the forward path towards the realization of low-cost energy devices in the commercial stream. The present work deals with an effective strategy wherein an efficient Pt-free electrocatalyst for oxygen reduction reaction (ORR) is prepared by stoichiometrically substituting some fraction of Fe with Zn in cobalt ferrite and anchoring these spinel nanoparticles on nitrogen doped reduced graphene oxide (N-rGO). Zn substitution is found to be significantly altering the ratio of Fe2+/Fe3+ in the cobalt ferrite nanocrystal system with a concomitant promotional influence on its electrocatalytic activity towards ORR. The nanoparticle composition with a Co, Fe and Zn molar ratio of 1.0:1.7:0.3, represented by the formula CoFe1.7Zn0.3O4(CFZn(0.3)), supported over N-rGO has shown 10 mV and 20 mV positive shift in the onset and half-wave potentials, respectively, for ORR in 0.1 M KOH in comparison to the nanoparticles of CoFe2O4 supported over N-rGO (CF/N-rGO). The optimum Zn substitution is found to be narrowing down the difference with the state-of-the-art Pt/C for ORR by 100 and 110 mV in terms of the onset and half-wave potentials, respectively. Most significantly, the homemade catalyst is found to be clearly outperforming the Pt catalyst in terms of the limiting current density and electrochemical durability.

}, keywords = {Carbon Nano-fiber, Cathod Catalyst, CoFe2O4, Evolution, Magnetic-properties, Membrane fuel- Cell, Metal-Air Batteries, N-doped graphene, Nanocrystalline, nanocrystals, oxygen reduction reaction, performance, Platinium, solvothermal synthesis, Zn substituted cobalt ferrite}, issn = {2365-6549}, doi = {10.1002/slct.201701684}, author = {Kashyap, Varchaswal and Singh, Santosh K. and Kurungot, Sreekumar} } @article {49443, title = {Synthesis framework for designing PtPdCoNiMn high-entropy alloy: a stable electrocatalyst for enhanced alkaline hydrogen evolution reaction}, journal = {Small}, volume = {21}, year = {2025}, month = {JAN}, type = {Article}, abstract = {

High entropy alloys (HEAs) are an emerging class of advanced materials characterized by their multifunctionality and potential to replace commercial catalysts in electrocatalytic water splitting. The synergy among the various alloyed elements in HEAs makes them particularly promising for applications in electrocatalysis. However, preparation of HEA via bottom-up approaches by avoiding the formation of mono, di, and tri metallic alloys in the nanoscale is challenging. This aspect is addressed, in this study by exploring the logical selection of solvents, reducing agents, and capping agents, along with their relative fractions, in the solvothermal synthesis of the HEA comprising platinum-palladium-cobalt-nickel-manganese (PtPdCoNiMn). It is established that the reducing capabilities of both the solvent and reducing agent are crucial for the reduction of each metal to form a single-phase HEA. The synthesized HEA (20 wt.\%)/functionalized carbon (FC) demonstrates excellent performance as an HER catalyst, exhibiting a low overpotential of 48.7 mV at -10 mA cm-2 in an alkaline electrolyte. This performance is characterized by high reaction kinetics and stability at elevated current densities. Furthermore, the catalyst shows impressive performance in both simulated and actual seawater. This development reduces the reliance on platinum while enhancing the long-term durability and catalytic efficiency of the electrocatalyst.

}, keywords = {electrocatalysts, HER, high entropy alloys, solvothermal synthesis}, issn = {1613-6810}, doi = {10.1002/smll.202408317}, author = {Chandran, M. Athira and Sahoo, Sudeshna and Singh, Ashutosh K. and Prasad, Bhagavatula L. V.} }