Graphene enhances Li storage capacity of porous single-crystalline silicon nanowires.
We demonstrated that graphene significantly enhances the reversible capacity of porous silicon nanowires used as the anode in Li-ion batteries. We prepared our experimental nanomaterials, viz., graphene and porous single-crystalline silicon nanowires, respectively, using a liquid-phase graphite exfoliation method and an electroless HF/AgNO3 etching process. The Si porous nanowire/graphene electrode realized a charge capacity of 2470 mAh g(-1) that is much higher than the 1256 mAh g(-1) of porous Si nanowire/C-black electrode and 6.6 times the theoretical capacity of commercial graphite. This relatively high capacity could originate from the favorable charge-transportation characteristics of the combination of graphene with the porous Si 1D nanostructure.
Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, United States.
Xiao-Liang
XL
Wang
Wei-Qiang
WQ
Han
D003460:Crystallization / Q000379:methods; D011211:Electric Power Supplies; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation*; D010316:Particle Size; D016062:Porosity; D012825:Silicon / Q000737:chemistry*
D006108:Graphite; D008094:Lithium; D012825:Silicon