RESUMO
VO2 (B) nanorods with average width ranging between 50-100 nm are synthesized via a hydrothermal method and the post hydrothermal treatment drying temperature is found to be influential in their overall phase and growth morphology evolution. The nanorods with unusually high optical bandgap for a VO2 material are effective in enhancing the thermal performance of ethylene glycol nanofluids over a wide temperature range as is indicated by the temperature dependent thermal conductivity measurements. Humidity and LPG sensors fabricated using the VO2 (B) nanorods bear testament to their efficient sensing performance, which can be partially attributed to the mesoporous nature of the nanorods.
RESUMO
NiO nanostructures were synthesized via a simple wet chemical solution method with varying calcination temperatures. The synthesized nanostructures were characterized by XRD, TG/DSC, FT-IR and high-resolution electron microscopy techniques. The nanostructures revealed dependence of particle size, stoichiometry, optical band gap and luminescence intensity on calcination temperatures. The materials exhibited efficient electrochemical properties with decent capacitance values. Ethylene-glycol-based nanofluids of these nanoparticles registered excellent thermal conductivity enhancement of 59-69% in the room temperature region and 125% enhancement at higher temperatures (80 ° C), establishing NiO to be a top-draw contender for high-performance heat transfer fluids.