Morphological and electrochemical study of MnOxOy nanoparticle layers prepared by electrospraying

作者：Marsalek Jiri; Chmelar Josef; Pocedic Jaromir; Kosek Juraj^*

来源：Chemical Engineering Science, 2015, 123: 292-299.

DOI：10.1016/j.ces.2014.10.044

• Electrospraying
• Manganese oxide nanoparticles
• Morphology evolution
• Electrochemistry
• Raman spectroscopy

We are using the electro-hydrodynamic atomization technique (also called electrospraying) for the deposition of fine nanoparticle thin layers of different morphologies. This deposition method has a potential to enable massive fabrication of nanostructured products, but it is necessary to optimize the spraying process to reach the required product qualities. We focus on the preparation of basic (without carbon additives) nanostructured manganese oxide layers deposited on stainless steel substrates. The system of nanostructured MnO2 (with additives) is commonly used as the electrode in energy storage applications (batteries, supercapacitors). The electrochemistry of deposited layers is influenced mainly by MnO2 morphology, which strongly depends on the spraying conditions. Here we carry out the basic study of the nanostructured manganese oxide layer morphology evolution and its electrochemical changes during: (i) the electrospraying deposition period, (ii) the thermal treatment of deposits, and (iii) the electrochemical oxidation. During the electrochemical oxidation the deposited layers change their morphology and structure resulting in fine nanostructured MnO2 in the form of nanorods. This is a desired product for energy storage applications as confirmed by cyclic voltammetry. Morphology and composition analyses were carried out using Raman microscopy, XPS, SEM and AFM. A comprehensive fundamental analysis of the manganese oxide deposition and transformation processes is presented with the emphasis on the evolution of the deposited layer morphology.

• 出版日期2015-2-17