Enhanced Secondary Battery Anodes Based on Si and Fe₃O₄ Nanoparticle Infilled Monodisperse Carbon Starburst Colloidal Crystals

the observed capacity fade, the poor calendar life, and a large hysteresis during cycling. [ 1 ] Strategies currently utilized to improve conductivity include addition of carbon, [ 32 ] use of a conductive scaffold [ 1,15,16 ] and carbon nanotubes, [ 30 ] and “coating” by graphene encapsulation. [ 17,33 ] However, even after conductivity is improved, the charge–discharge hysteresis remains signifi cant. Some of the hysteresis is likely due to activation barriers for the reduction and oxidation reactions, which may be a function of the size and uniformity of the Fe 3 O 4 active materials formed after the fi rst discharge. [ 1 ] Fe 3 O 4 nanoparticle-based anodes have been investigated as a route to decrease this barrier; however, particle aggregation is a problem. [ 15,17,30,33,34 ] Interestingly, when Fe 3 O 4 nanoparticles were decorated on graphene sheets, the hysteresis was reduced to 0.7 V, as compared to that of 0.9 V for a graphene-free Fe 3 O 4 anode. [ 34 ]