Lead citrate precursor route to synthesize nanostructural lead oxide from spent lead acid battery paste

Abstract Nanostructural lead oxides were prepared by the decomposition of a new type of lead citrate precursor (Pb 3 (C 6 H 5 O 7 ) 2 ·3H 2 O), which was synthesized through leaching of spent lead acid battery paste in citrate salt aqueous system and more economical compared with former precursor (Pb(C 6 H 6 O 7 )·H 2 O). The products were characterized by thermogravimetric–differential thermal analysis, scanning electron microscopy and X-ray diffraction. The results show that when lead citrate of columnar-shape crystals are calcined in N 2 gas, orthorhombic β-PbO is the main product containing small amount of Pb and C. On combusting the citrate in air, a mixture of orthorhombic β-PbO, tetragonal α-PbO and Pb with the particle size of 100–200 nm is obtained, with β-PbO as the major product. And the cyclic voltammetry measurements of lead oxides present different electrochemical redox potentials because of the different structure of lead oxide obtained from Pb 3 (C 6 H 5 O 7 ) 2 ·3H 2 O.