Exothermic low temperature sintering of Cu nanoparticles

Sintering of the Cu nanopartide at low temperatures resulted in exothermic behavior after its initiation. The calorimetry study of the heating of a 20 nm copper nanoparticles agglomerate revealed the evolution of 41.17 J/g of heat between 170 degrees C and 270 degrees C. High resolution transmission electron microscopy (HRTEM) images indicated that the heat generation was accompanied by sintering. The surface energy of the 20 nm copper nanopartides was estimated to be 1.23 x 10(3) erg/cm(2) based on the heat released during sintering. The in situ high resolution transmission electron microscope (HRTEM) investigation showed that vigorous sintering occurred between 217 and 234 degrees C, which took place through the dislocation sintering mechanism. (C) 2015 Elsevier Inc. All rights reserved.