Synthesis of uniform nano-structured lead oxide by sonochemical method and its application as cathode and anode of lead-acid batteries Hassan Karami a, * , Mohammad Ali Karimi b , Saeed Haghdar b a Department of Chemistry, Payame Noor University, Abhar, Iran b Department of Chemistry, Payame Noor University, Ardakan, Iran Received 22 June 2007; received in revised form 22 October 2007; accepted 16 November 2007 Available online 26 November 2007 Abstract This paper discusses the results of a research aimed at investigating the synthesis of nano-structured lead oxide through reaction of lead nitrate solution and sodium carbonate solution by the sonochemical method. At the first, lead carbonate was obtained in a synthesized solution and then, after filtration, it was calcinated at the temperature of 320 8C so that nano-structured lead oxide can be produced. The effects of different parameters on particle size and morphology of final lead oxide powder were optimized by a ‘‘one at a time’’ method. The prepared lead oxide powder was characterized by scanning electron microscopy (SEM), transmission electron spectroscopy (TEM) and X-ray diffraction (XRD). Under optimum conditions, uniformed and homogeneous nano- structured lead oxide powder with more spongy morphology and particle size of 20–40 nm was obtained. The synthesized lead oxide, as anode and cathode of lead-acid batteries, showed an excellent discharge capacity (140 mA h/g). # 2007 Elsevier Ltd. All rights reserved. Keywords: A. Nanostructures; B. Chemical synthesis; C. Electrochemical measurements; C. Electron microscopy; D. Energy storage 1. Introduction The overall goal of this program was to obtain an easy method for synthesizing more porous nano-structured lead oxide. Such structure probably can be useful as pigment and active material of lead-acid batteries. During the last few years, the synthesis of nano-structured oxide materials has attracted considerable attention [1–5]. Lead element has a lot of oxide forms including PbO (a, b and amorphous), Pb 2 O 3 , Pb 3 O 4 , PbO 2 (a, b and amorphous). Among lead oxides, lead dioxide has been studied more than other forms. A number of electrochemical techniques have been used to prepare lead dioxide, which included constant current and constant potential [6], cyclic voltammetry [7] and pulse current [8]. Shen and Wei [6] deposited lead dioxide from a solution containing Pb 2+ on three different substrates (i.e. Au, Pt and Ti) with different techniques. Morales and et al. synthesized lead dioxide by using various methods in the range of nanometric to micrometric size and tested the obtained particles as positive active material in lead-acid cells [9]. Bervas et al. synthesized the nanosized a- PbO 2 and b-PbO 2 at room temperature by a low-cost solution technique involving the chemical oxidation of lead www.elsevier.com/locate/matresbu Materials Research Bulletin 43 (2008) 3054–3065 * Corresponding author. E-mail address: karami_h@yahoo.com (H. Karami). 0025-5408/$ – see front matter # 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.materresbull.2007.11.014