Highly oriented macroporous graphene hybrid monoliths for lithium ion battery electrodes with ultrahigh capacity and rate capability.

The highly oriented macroporous graphene monoliths hybridized with carbon-coated metal oxide or phosphate (C/M/GM) with core/shell structure were fabricated by an ice-templating co-assembly of M/GO nanosheets (metal oxide/phosphates decorated graphene oxide) and polyvinyl alcohol (PVA), and following thermal treatment. With either tin oxide (SnO 2 ) or iron phosphate (FePO 4 ), the resulting C/M/GMs possess periodic macropores with diameters ranging from 5 to 20 μm and high loading contents of active components (~70 wt%). Served as the anode in LIBs, C/SnO 2 /GM maintains an ultrahigh capacity of 1665 mA h g −1 at a current density of 0.2 A g −1 for 200 cycles. Even at an ultrafast charge rate of 10 A g −1 , a decent capacity of 300 mA h g −1 can still be achieved, with excellent cycling stability. And C/FePO 4 /GM also delivers a highly reversible capacity of 175 mA h g −1 at a current density of 0.05 A g −1 for 150 cycles and a good capacity of 57 mA h g −1 at 2 A g −1 when as the LIB cathode electrode. [ABSTRACT FROM AUTHOR]