Aqueous Nanofluids Based on Copper MPA: Synthesis and Characterization

Abstract

The application and use of efficient cooling fluids have become increasingly important due to the increasing industrial and energy demand associated with the miniaturization of various electronic devices. The search for high-efficiency heat exchanger fluids in the early 1990s led to the development of a new class of refrigerants called nanofluids. The use of nanofluids is linked to obtaining stable colloidal dispersions which exhibit high thermal conductivity. For this purpose, the efficiency of a nanofluid will depend on the type of fluid used and the dispersed nanomaterial. In this work, a stable aqueous nanofluid based on mercaptopropionic acid-coated copper sulfide nanoparticles (Cu 2 S/MPA), synthesized by the chemical reduction method, was developed. The nanofluid presented colloidal stability in alkaline medium and an average increase of 36% in thermal conductivity for a volumetric fraction of 0.05%.

Ligand-Tuned Energetics for the Selective Synthesis of Ni2P and Ni12P5 Possessing Bifunctional Electrocatalytic Activity toward Hydrogen Evolution and Hydrazine Oxidation Reactions

“…For both Ni 2 P-Cys and Ni 2 P-MPA, bands at 1610 cm −1 characteristic of the carboxylate group and those around 2900−3000 cm −1 characteristic of the amino group appeared. 25,26 This confirms the presence of the ligands on the surface of nickel phosphide (Figure 3a,b). Interestingly, the peaks corresponding to the −S−H (2550−2670 cm −1 ) were absent in both Ni 2 P-Cys and Ni 2 P-MPA.…”

“…To comprehend the nature of interactions between ligand molecules and as-synthesized nickel phosphides, we compared the Fourier transform infrared (FT-IR) spectroscopy features of nickel phosphide with those of the ligands used during the corresponding synthesis. For both Ni 2 P-Cys and Ni 2 P-MPA, bands at 1610 cm –1 characteristic of the carboxylate group and those around 2900–3000 cm –1 characteristic of the amino group appeared. , This confirms the presence of the ligands on the surface of nickel phosphide (Figure a,b). Interestingly, the peaks corresponding to the −S–H (2550–2670 cm –1 ) were absent in both Ni 2 P-Cys and Ni 2 P-MPA.…”

Synthesis of anisotropic Cu2−xS-based nanostructures by thermal oxidation

“…In the case of nCu:nS of 2:1, the spectra show a peak at 476 cm -1 that is specific to Cu-O vibrations [33]. Moreover, for all measured samples, bands attributed to copper sulfate (619 cm -1 ) and the SO 4 2group (496 and 1124 cm -1 ) are visible [34][35][36]. In addition, modes assigned to the residue of the precursor are present.…”

“…In the temperature between 25 and 200°C, spectra show no vibrations band, which suggests that the bonds present in the material are inactive in this range of infrared region. Above 200°C bands attributed to copper sulfate (617 cm -1 ) and the SO 4 2group (1109 cm -1 ) are visible [34][35][36]. According to Eq.…”

Contribution to the Study of Fluid Flow in a Stirred Tank by Introducing Microparticles

“…There are two strong demands in the industry: firstly, ensure the quality of finished products. Secondly, work in a more and more concentrated environment for pollution and cost problems, in order to know and check all the involved aspects in the process, in particular hydrodynamics and heat transfer [28,29].…”