Synthesis of Mesoporous Single Crystal Co(OH)2 Nanoplate and Its Topotactic Conversion to Dual-Pore Mesoporous Single Crystal Co3O4

A new class of mesoporous single crystalline (MSC) material, Co(OH)(2) nanoplates, is synthesized by a soft template method, and it is topotactically converted to dual-pore MSC Co3O4. Most mesoporous materials derived from the soft template method are reported to be amorphous or polycrystallined; however, in our synthesis, Co(OH)(2) seeds grow to form single crystals, with amphiphilic block copolymer F127 colloids as the pore producer. The single crystalline nature of material can be kept during the conversion from Co(OH)(2) to Co3O4, and special dual-pore MSC Co3O4 nanoplates can be obtained. As the anode of lithium-ion batteries, such dual-pore MSC Co3O4 nanoplates possess exceedingly high capacity as well as long cyclic performance (730 mAh g(-1) at 1 A after the 350th cycle). The superior performance is because of the unique hierarchical mesoporous structure, which could significantly improve Li+ diffusion kinetics, and the exposed highly active (111) crystal planes are in favor of the conversion reaction in the charge/discharge cycles.