Highly robust silicon nanowire/graphene core–shell electrodes without polymeric binders

Abstract

A large theoretical charge storage capacity along with a low discharge working potential renders silicon a promising anode material for high energy density lithium ion batteries. However, up to 400% volume expansion during charge-discharge cycling coupled with a low intrinsic electronic conductivity causes pulverization and fracture, thus inhibiting silicon's widespread use in practical applications. We report herein on a low cost approach to fabricate hybrid silicon nanowire (SiNW)/graphene nanostructures that exhibit enhanced cycle performance with the capability of retaining more than 90% of their initial capacity after 50 cycles. We also demonstrate the use of hot-pressing in the absence of any common polymer binder such as PVDF to bind the hybrid structure to the current collector. The applied heat and pressure ensure strong adhesion between the SiNW/graphene nano-composite and current collector. This facile yet strong binding method is expected to find use in the further development of polymer-binder free anodes for lithium ion batteries.

Design Considerations for Unconventional Electrochemical Energy Storage Architectures

“…In some cases, surface functionalization was found to lead to improved graphene–active material interface . Several Li‐ion battery materials have been tested using this fabrication approach and displayed improved cycling performances upon graphene incorporation …”

GaN nanowire ultraviolet photodetector with a graphene transparent contact

“…Graphene has been used as a growth substrate for nanowires 1,2 as well as an electrode material. 3 The graphene/nanowire hybrid materials have demonstrated their promise for a broad range of applications, in particular for energy harvesting and storage devices such as solar cells, 3,4 piezogenerators 5 or supercapacitor electrodes, 6 for light emitting diodes 7,8 as well as for gas sensing devices. 9 Several nanowire/graphene photodetectors have been recently reported based on CdS 10 and ZnO 11,12 nanowires.…”

Cu3Si@Si core–shell nanoparticles synthesized using a solid-state reaction and their performance as anode materials for lithium ion batteries

“…After 6 h, the EDX mapping images ( Fig. 29 At the same time, the sharp peak 20 below 0.1 V appearing in the 1st cycle represents the alloy reaction of crystallized Si and Li + . TEM image of Sample-6 h (Fig.…”