Nanocrystals (NCs) present unique physicochemical properties arising from their size and the presence of ligands. Comprehending and controlling the ligand− crystal interactions as well as the ligand exchange process is one of the central themes in NC science nowadays. However, the relationship between NC structural disorder and the ligand exchange effect in the NC atomic structure is not yet sufficiently understood. Here we combine pair distribution function analysis from electron diffraction data, extended Xray absorption fine structure, and high-resolution transmission electron microscopy as experimental techniques and first-principles density functional theory calculations to elucidate the ligand exchange effects in the ZrO 2 NC structure. We report a substantial decrease in the structural disorder for ZrO 2 NCs caused by strain rearrangements during the ligand exchange process. These results can have a direct impact on the development of functional nanomaterials, especially in properties controlled by structural disorder.

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This work reports the synthesization of nanoparticles cobalt oxide (Co 3 O 4 ) with no secondary phase by a modified sol-gel method and its structural morphological and electrochemical characterizations. FTIR, XRD and Raman analysis showed the formation of spinel cobalt oxide with no secondary phase. TEM images revealed that an undefined morphology with average crystallite size estimated by Scherrer's equation was found to be 30 nm. Experiments of cyclic voltametric, galvanostatic chargedischarge and impedance spectroscopy were evaluated at 1 mol L -1 KOH and revealed an intrinsic pseudocapacitance. The studies of complex capacitance and complex power revealed the resistive and capacitive characteristics with a specific capacitance of 120 F g -1 .