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.

Supporting Information:I. Detailed process for the synthesis of the core NPs. Synthesis of hexagonal phase (β) NaGdF 4 :Yb,Er core NPs:The synthesis of the core NPs with a size of ~ 4.5 nm in this work were similar to previously report by van Veggel et al. 1 In a typical procedure, GdCl 3 (0.8 mmol), YbCl 3 (0.18 mmol), ErCl 3 (0.02 mmol), OA (4 mL) and ODE (15 mL) were mixed together and heated to 140 °C under vacuum until a clear solution formed, after that, the solution was cooled to room temperature. A solution of NaOH (2.5 mmol) and NH 4 F (4 mmol) in methanol (10 mL) was added and the mixture was stirred for a few hours. The reaction mixture was then heated at 70 °C to remove the methanol. Afterward, the solution was heated to 270 °C and maintained for 45 min under a gentle argon flow. Subsequently, the solution was cooled to room temperature and the NPs precipitated, centrifuged and washed twice with ethanol. The NPs were finally dispersed in 10 mL of cyclohexane for further use. Synthesis of cubic phase (α) small core NPs with (NaYbF 4 :Er) and without (NaYF 4 ) dopants:The trifluoroacetates (TFA) of Y, Yb, Tm, and Er were prepared by the procedure reported by Roberts et al. 2 The syntheses of the core NPs in this work were similar to that reported previously by Chen et al. 3 In a typical procedure (NaYbF 4 :Er, ~ 9 nm), 1.00 mmol of Na-TFA, 0.90 mmol of Yb-TFA, and 0.10 mmol of Er-TFA were dispersed in 16.0 mL of OA and 8.0 mL of OAM. The result solution was then heated at 120 °C under vacuum with magnetic stirring for 30 min to remove water and oxygen. Finally, the solution was heated to 275 °C at a rate of about 15 °C/min under Ar gas protection and kept at this temperature under vigorous stirring for about 30 min. Finally, the mixture was cooled to room temperature precipitated,

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A novel ligand‐assisted assembly approach is demonstrated for the synthesis of thermally stable and large‐pore ordered mesoporous titanium dioxide with a highly crystalline framework by using diblock copolymer poly(ethylene oxide)‐b‐polystyrene (PEO‐b‐PS) as a template and titanium isopropoxide (TIPO) as a precursor. Small‐angle X‐ray scattering, X‐ray diffraction (XRD), transmission electron microscopy (TEM), high‐resolution scanning electron microscopy, and N2‐sorption measurements indicate that the obtained TiO2 materials possess an ordered primary cubic mesostructure with large, uniform pore diameters of about 16.0 nm, and high Brunauer–Emmett–Teller surface areas of ∼112 m2 g−1, as well as high thermal stability (∼700 °C). High resolution TEM and wide‐angle XRD measurements clearly illustrate the high crystallinity of the mesoporous titania with an anatase structure in the pore walls. It is worth mentioning that, in this process, in addition to tetrahydrofuran as a solvent, acetylacetone was employed as a coordination agent to avoid rapid hydrolysis of the titanium precursor. Additionally, stepped evaporation and heating processes were adopted to control the condensation rate and facilitate the assembly of the ordered mesostructure, and ensure the formation of fully polycrystalline anatase titania frameworks without collapse of the mesostructure. By employing the obtained mesoporous and crystallized TiO2 as the photoanode in a dye‐sensitized solar cell, a high power‐conversion efficiency (5.45%) can be achieved in combination with the N719 dye, which shows that this mesoprous titania is a great potential candidate as a catalyst support for photonic‐conversion applications.

Ordered mesoporous materials have attracted much attention since their discovery owing to their outstanding properties, such as tunable pore sizes and mesostructures, variable morphologies, high surface areas, and large pore volumes. [1][2][3][4][5][6][7][8] These features make them promising candidates for applications including catalysis, [9] adsorption and separation, [10] chemical sensing, [11] and biomedicine. [12] To date, significant advances have been achieved in the synthesis of mesoporous materials, particularly in the soft templating approach using surfactants or block copolymers as the templates (structuredirecting agents), and enormous ordered mesoporous materials with variable pore structures, pore sizes, and framework compositions have been prepared.Apart from exploring the methods of synthesis and strategies, considerable efforts have been devoted to designing functional ordered mesoporous materials by introducing functional nanomaterials or organic groups for practical applications. For example, using sol-gel chemistry, many functional mesoporous composites have been synthesized by coating functional nanoparticles. [13,14] Furthermore, functional organic groups or nanoparticles have been introduced into mesopores, resulting in various functional mesoporous materials that are useful in drug delivery, chemical sensing, and catalysis. [15][16][17][18][19] Particularly the immobilization of sulfonic acid groups (-SO 3 H) in mesopores have aroused great research interest because the mesoporous materials can provide a large accessible surface area for supporting high density of acidic sites, thus serving as efficient solid Brønsted acids.[18] Compared to traditional homogeneous acid catalysts (such as H 2 SO 4 , AlCl 3 , BF 3 ), the novel heterogeneous catalysts are environmentally benign and can be readily recycled from reaction medium, thus reducing the energy consumption for the production of chemicals.To introduce sulfonic acid groups on the pore walls of mesoporous silica materials, typical methods involve the attachment of sulfur-containing organic silanes (for example ÀSH, ÀSÀSÀ) by post-grafting or co-condensation and subsequent oxidation with hydrogen peroxide.[20] Van Rhijn et al.[18a] first reported the synthesis of ordered mesoporous silicas functionalized with SO 3 H groups using co-condensation or post-modification. The obtained SO 3 H-functionalized mesoporous silicas exhibited good performance in catalyzing the condensation of 2-methylfuran with acetone with high conversion (85 %) and selectivity (96 %) toward the target product 2,2-bis(5-methylfuryl)propane. By contrast, traditional microporous solid acids, such as H-b and H-US-Y zeolites, exhibited much lower conversion (ca. 60 %) and selectivity (ca. 70 %) owing to the undesired fast formation and adsorption of tarry oligomeric compounds in the narrow zeolite pores and subsequent catalyst deactivation. This result suggests that the immobilization of SO 3 H groups in mesoporous silicas with larger pore is more favorable for catalysi...