We report a new solution deposition method to synthesize an unprecedented type of two-dimensional ordered mesoporous carbon nanosheets via a controlled low-concentration monomicelle close-packing assembly approach. These obtained carbon nanosheets possess only one layer of ordered mesopores on the surface of a substrate, typically the inner walls of anodic aluminum oxide pore channels, and can be further converted into mesoporous graphene nanosheets by carbonization. The atomically flat graphene layers with mesopores provide high surface area for lithium ion adsorption and intercalation, while the ordered mesopores perpendicular to the graphene layer enable efficient ion transport as well as volume expansion flexibility, thus representing a unique orthogonal architecture for excellent lithium ion storage capacity and cycling performance. Lithium ion battery anodes made of the mesoporous graphene nanosheets have exhibited an excellent reversible capacity of 1040 mAh/g at 100 mA/g, and they can retain at 833 mAh/g even after numerous cycles at varied current densities. Even at a large current density of 5 A/g, the reversible capacity is retained around 255 mAh/g, larger than for most other porous carbon-based anodes previously reported, suggesting a remarkably promising candidate for energy storage.

Nanoparticles with ordered mesostructures benefit from advantages resulting from the remarkable and complementary property of the mesochannels and quantum effects in the nanoscale. Their open-framework structures, large surface area and porosity, and nanosize make ordered mesoporous nanoparticles useful in adsorption, [1][2][3] controlled drugs release, [4][5][6][7][8][9] cellular delivery, [10][11][12][13][14][15][16] energy storage, [17][18][19][20][21][22] and catalysis.[23] Among mesoporous nanoparticles, silicates have been extensively synthesized by a well-controllable process based on sol-gel chemistry. Mesoporous carbon materials have many advantages over silica materials, such as electrical conductivity, chemical inertness, hydrophobic property, which enable them to be widely used as supercapacitors, [17,18] fuel cells, [19,20] lithium batteries, [22] and hydrophobic drugs carriers.[12] Similar to silica, carbon nanoparticles are nontoxic, biocompatible, and nonimmunogenic, which allows them to be used extensively in cellular delivery. [15,16] Therefore, many efforts have been made to fabricate mesoporous carbon nanoparticles. In general, a nanocasting strategy was adopted by employing nanosized mesoporous silica as a hard template. [15,[24][25][26][27][28][29] Nevertheless, nanocasting is a very fussy, highcost, and thus industrial unfeasible method.[30] Also, the mesostructures and morphologies of the replicated carbon nanoparticles are limited to the parent silica template. However, small mesoporous carbon nanoparticles are difficult to obtain by hard-templating approach because of the aggregation and cross-linking tendency of the nanosized silicate templates and the carbon resource. [10,11] Recently, an organic-organic assembly method has been successfully developed to synthesize ordered mesoporous carbons with various structures by using amphiphilic triblock copolymers as a soft template and phenolic resol as a carbon source. [31][32][33][34][35][36][37] Two routes can be used to prepare the mesoporous carbon materials, one is the well-known evaporation induced selfassembly (EISA) method in ethanol solution, and another is aqueous solution route under a "hydrothermal" [38][39][40][41] conditions at a low temperature of 60-70 8C. Morphologies of the mesoporous carbon materials synthesized from the EISA strategy are usually films and monolithic, whereas the aqueous route usually yields powder carbon materials with particle sizes in the micrometer or millimeter scale. More recently, mesoporous carbon microspheres with the diameter over 50 mm were synthesized by a suspension assisted method, which was developed by Long and co-workers. [42] In this work, the spherical diameters were limited to micrometer-sized emulsion droplets. In this case, ordered mesoporous carbon nanoparticles are difficult to synthesize under the present conditions. To the best of our knowledge, there are no reports of the direct synthesis of ordered mesoporous carbon nanoparticles, especially nanospheres with uniform size.Herein, ...

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A sandwich-like 2D-mesoporous-carbon/MoS -nanosheet heterostructure is fabricated for the first time. The hybrid structure is composed of three well-stacked monolayers: an ordered-mesoporous-carbon monolayer, a MoS monolayer, and a further ordered-mesoporous-carbon monolayer. This unique heterostructure exhibits excellent electrochemical performance as an anode material for lithium-ion batteries.