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Growth kinetics evaluation of hydrothermally synthesised Co2(OH)3Cl nanoparticles for application in solar thermal heat transfer fluids.

Version 3 2025-02-05, 08:36
Version 2 2024-08-13, 05:59
Version 1 2024-07-02, 09:14
dataset
posted on 2025-02-05, 08:36 authored by Patricia NtumbaPatricia Ntumba

This research project reports a novel type of nanofluid consisting in the addition of cobalt hydroxychloride (Co2(OH)3Cl) nanopowders to pure water via a two-step method. Co2(OH)3Cl nanoparticles were synthesized via hydrothermal precipitation at varying propanol concentrations ranging from 0% to 100%. Morphological analysis revealed hexagonally shaped Co2(OH)3Cl nanoplates with average sizes ranging from 83.6 nm to 56.1 nm at propanol concentrations below 50%. In contrast, spherical Co2(OH)3Cl nanoparticles, with average sizes ranging from 22.6 nm to 9.6 nm, were formed at propanol concentrations higher than 50%. Thermal conductivity analysis of the prepared nanofluids were performed at temperatures ranging from 298 K to 318 K. The use of both experimental and molecular dynamics simulation method to determine their thermal conductivity at different temperature, nanoparticle size, and shape was also reported. The thermal conductivity of nanofluids prepared with Co2(OH)3Cl nanoparticles of the smallest diameter (9.6 nm) showed the highest enhancement (17.7%) at a temperature of 318 K compared to pure water. Viscosity analysis of the prepared nanofluids was performed at temperatures ranging from 298 K to 308 K. At 303 K, the nanofluid made of Co2(OH)3Cl nanoplates at ~58 nm displayed an increase in viscosity of ~11%. Moreover, the growth of Co2(OH)3Cl in the presence of 70% propanol and water has been studied over time. In water, Co2(OH)3Cl nanoplates grew first via OR kinetics then OA kinetics whereas a simultaneous OR and OA growth kinetics occurred for nanospheres. In 70% propanol, the growth of Co2(OH)3Cl nanospheres was controlled first by OR kinetics, then by OA kinetics. This novel nanofluid holds considerable potential for application as an advanced heat transfer fluid in medium-temperature solar collector systems.

History

Is this dataset for graduation purposes?

  • Yes

Supervisor email address

FesterV@cput.ac.za