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TiO 2 -coated Fe 2 O 3 composites exhibiting high electrochemical stability with oxygen defects were synthesized as the anode materials of Li-ion batteries using an easy sol−gel method. The industrial submicron-sized Fe 2 O 3 with no special shape and commercial tetrabutyl titanate were adopted as raw materials. The phase structures, morphologies, and elements distribution on the surface were characterized by X-ray diffraction analysis, electron paramagnetic resonance, scanning electron microscopy, X-ray photoelectron spectroscopy, and so forth. Results indicated that TiO 2 was well coated on the surface of raw Fe 2 O 3 with an average thickness of 5.5 nm, and the oxygen defects were successfully introduced into the composites with the reduction treatment. Electrochemical characterization indicated that TiO 2 coating was beneficial to the cycle performance of Fe 2 O 3 . The coating layer significantly improved the electronic conductivity and cycling stability of the Fe 2 O 3 anode material, as theoretically supported by the density functional theory calculation. Moreover, the introduction of oxygen defects in samples resulted in more excellent cycling stability compared to that in samples without reduction. The reduced Fe 2 O 3 @0.2TiO 2 sample exhibited a specific discharge capacity of 405.6 mA h•g −1 after 150 cycles, which effectively improved the intrinsic cycling performance of Fe 2 O 3 , and a corresponding discharge capacity of 50 mA h•g −1 after 30 cycles.

Hereinafter, we report onion-like carbon (OLC) and fullerene-like carbon (FLC) materials synthesized via 2,4,6-trinitrotoluene (TNT) and 1,3,5-trinitro-1,3,5-triazine (Royal Demolition Explosive, RDX) detonation technique and acetylene gas explosion process, respectively. Abundant micropores, mesopores, and different spatial structures exist inside the two carbon materials. They demonstrate good conductivity and sulfur storage capacity, and various rich pore structures, inhibiting the shuttle effect of the solved lithium polysulfide in the charge–discharge process. The pore size distribution, pore volume, specific surface area, electronic conductivity, composite structure, interaction between sulfur and carbon, and cell performance are researched. The Li–S battery furnished with the two carbon–sulfur hybrid materials as the cathode host material delivers a well reversible rate cycling performance, and a low decay rate of 0.037% and 0.056% per cycle during 1000 cycles at 1C for FLC and OLC, respectively, with a sulfur load of about 2.2 mg/cm2. The excellent electrochemical performance of the two carbon materials obtained by detonation method makes them ideal substitute products of the commercial Super P carbon material, especially the FLC material.

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