Monodispersed hard carbon spherules with uniform nanopores

Hard carbon with perfect spherical morphology was prepared for the first time by a hydrothermal method. It has controllable monodispersed particle size and a smooth surface. Transmission electron microscopy shows that there are a large quantity of uniform nanopores of about 0.4 nm in diameter and only very few parallel graphene sheets exist within the spherules. This hard carbon material has a specific BET surface area of 400 m2/g for N2 as adsorbate, and can reversibly store lithium up to 430 mAh/g. This shows convincingly that carbon nanopores can store a large quantity of lithium.