| PbO2 is widely employed as an anode in the chemical industry, as it has high conductivity, excellent corrosion resistance, chemical stability, high current tolerance and low cost. If the functional nanomaterials could be dispersed into PbO2 matrix, they would benefit each other through synergetic effects arising from the intimate electronic interaction of the components. The novel PbO2 matrix composite electrode materials will have special properties.In this study, we have synthesized nano-Co3O4, nano-Mn3O4, nano-WO3 and nano-SnO2, respectively, via one-step homogeneous precipitation at low temperature and hydrothermal synthesis method. Subsequently, the nano-Co3O4+PbO2, nano-Mn3O4+PbO2, nano-WO3+PbO2 and nano-SnO2+PbO2 composite electrode materials are prepared by anodic composite electrocodeposition on Ti substrate. Furthermore, we have studied the controllable preparation conditions, structure, composition, electro-properties and applications of these four composites in detail. The resultes indicate that the novel PbO2 matrix composite electrode materials have promising application potentials in the fields of electro-catalytic and storage.Electrolytic deposition of composite oxides was performed in a three-electrode electrolytic cell under constant-potential control. The 100 mL of electrolytic solution consisted of 0.1 mol/L Pb(NO3)2 and suspended nano-particles/sheets, the pH value of the electrolyte is about 3～4. It is found that the embedded nano-particles/sheets concentration is increased with the increasing concentration of the nano-particles/sheets suspended in the planting. However, the content of the particles/sheets embedded increased to a limiting value. The optimal preparation conditions for the composites were as follows:deposition potential is 1.4 V; electrolytic solution consisted of 20% acetone and 80% water; deposition time is 2 h; deposition temperature is room temperature.The composite on the electrode surface is composed of spinel nano-Co3O4 andβ-PbO2. Composite porosity and specific area increase and the grains decrease with the nano-Co3O4 doping content increasing. The composite shows excellent activity for OER (oxygen evolution reaction) and high-capacity in alkaline medium, owing to the intimate electronic interaction between PbO2 and nano-Co3O4, and the porosity of the composite. Electrical tests indicate that the overpotentials of the composites for OER shift to the negative, whereas the onset potential (Eonset) decreases by approximately 160 mV to the maximal degree. The nano-Co3O4+PbO2 composite shows the highest specific capacitance up to～220 F/g.The nano-Mn3O4+PbO2 composite is composed of tetragonalγ-Mn3O4 andβ-PbO2. Composite porosity and specific area increase and the grains decrease with the nano-Mn3O4 doping content increasing. It is a porous quasi-3D material with a maximum electrochemically effective area ratio (RF) of 72. The composite shows excellent activity for OER and high-capacity in neutral medium. This could be attributed to the intimate electronic interaction between PbO2 and nano-Mn3O4, and the porous quasi-3D structure of the composite. The activity for OER and capacity is improving with the embedded nano-Mn3O4 increasing. The Eonset decreases by approximately 160 mV to the maximal degree. The nano-Mn304+Pb02 composite shows high specific capacitance up to～340 F/g.The nano-WO3+PbO2 composite is composed of WO3·H2O andβ-PbO2. Composite porosity and specific area increase and the grains decrease with the nano-WO3 doping content increasing. It is a porous material with a maximum electrochemically effective area ratio (RF) of 57. The composite shows excellent activity for OER and high-capacity in acidic medium. This could be attributed to the intimate electronic interaction between PbO2 and nano-WO3, and the porous structure of the composite. The activity for OER and capacity is improving with the embedded nano-WO3 increasing. The Eonset decreases by approximately 200 mV to the maximal degree. The nano-WO3+PbO2 composite shows high specific capacitance up to～320 F/g.The nano-SnO2+PbO2 composite is composed of rutile phase SnO2 andβ-PbO2. Composite specific area increase and the grains decrease with the nano-SnO2 doping content increasing. The Eonset of the composite is similar to SnO2 andβ-PbO2, which is about 1.9 V～2.0 V. Owing to the intimate electronic interaction between PbO2 and nano-SnO2, the nano-SnO2+PbO2 composite shows high specific capacitance up to～208 F/g.
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