In this work, a highly ordered mesoporous carbon nitride nanorods with 971–1124 m2 g–1 of superhigh specific surface area, 1.31–1.79 cm3 g–1 of ultralarge pore volume, bimodal mesostructure, and 9.3–23 wt % of high N content was prepared via a facile nanocasting approach using SBA-15 as template and hexamethylenetetramine as carbon nitride precursor, and the specific surface area and pore volume as well as N content are strongly dependent on the chosen precursor and pyrolysis temperature. The as-prepared materials were well characterized by HRTEM, FESEM, XRD, BET, Raman, FT-IR, XPS, and the textural structure and morphology were confirmed. The finding breaks through the bottleneck problems for fabricating mesoporous carbon nitride with both ultrahigh surface area and super large pore volume by employing an unexplored hexamethylenetetramine as carbon nitride precursor. The current synthetic strategy can be extended to the preparation of various mesoporous carbon nitride with different textural characteristics by using diverse templates under changeable preparation conditions. The developed mesoporous carbon nitride material with 750 °C of pyrolysis temperature exhibits high superior catalytic performance, ascribed to the promoting effect of nitrogen within the carbon matrix, the rich CO group and defect/edge feature on the surface, small size of graphitic crystallite, as well as the ultrahigh surface area and pore volume. It can also be concluded that the microstructures including bulk and surface structure features and surface chemical properties of the carbon-based materials have a decisive influence on their catalytic performance. The developed material can be employed in various organic transformations such as the base-catalyzed reactions, selective oxidation, dehydrogenation, photocatalysis, and electrocatalysis as well as acting as a novel and efficient candidate for CO2 capture, supercapacitor, purification of contaminated water, and future drug-delivery systems.

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Framework titanium atoms in titanium-substituted silicalite (TS-1) can be identified by UV resonance Raman spectroscopy since the associated Raman bands at 1125, 530, and 490 cm(-1) (see figure) are observed only when the charge transfer transition associated with the framework Ti atoms is excited by a UV laser. Thus, framework Ti atoms can be distinguished from nonframework Ti atoms and other defect sites. This method can be applicable to identifying transition metal atoms in the frameworks of other molecular sieves.

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Framework titanium atoms in titanium-substituted silicalite (TS-1) can be identified by UV resonance Raman spectroscopy since the associated Raman bands at 1125, 530, and 490 cm(-1) (see figure) are observed only when the charge transfer transition associated with the framework Ti atoms is excited by a UV laser. Thus, framework Ti atoms can be distinguished from nonframework Ti atoms and other defect sites. This method can be applicable to identifying transition metal atoms in the frameworks of other molecular sieves.

Owing to their unique structural features and surface properties, graphene and nanodiamond have attracted tremendous attention in diverse fields. However, restacking of graphene and reagglomeration of dispersed nanodiamond inevitably depress their catalytic properties. Herein, inspired by the historic discovery of “pillared clay”, we successfully realized the simultaneous inhibition of their restacking by fabricating a N‐doped mesoporous graphene/nanodiamond (N‐RGO/ND) nanocomposite by a facile wet‐chemical approach. The electrocatalytic oxygen reduction reaction (ORR) and the thermocatalytic oxidant‐free and steam‐free direct dehydrogenation (DDH) of ethylbenzene were used to examine its catalytic properties. The nanocomposite showed synergistically improved catalytic DDH and electrocatalytic ORR activity relative to that of the individual components, which can be ascribed to synergy between graphene and nanodiamond and to the large surface area, well‐ordered mesoporous structure, small crystalline size, and rich defect and CO surface features. Moreover, the developed synthetic strategy in this work can be extended to diverse N‐doped nanocomposites from dispersion‐required carbon precursors.

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Nitrogen‐doped carbon nanotubes (CNTs) with defect‐ and CO‐group‐rich surface features were fabricated through a facile and scalable physical dry milling and subsequent pyrolysis approach of carbon nanotubes and melamine in the presence of guanidine nitrate. The catalytic performance of the as‐prepared N‐doped CNTs with diverse guanidine nitrate dosages and pyrolysis temperatures for direct dehydrogenation of ethylbenzene to styrene under oxidant‐ and steam‐free conditions was measured. Various characterization techniques including high‐resolution transmission electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, nitrogen–adsorption and thermogravimetric analysis, and Raman spectroscopy were employed to investigate the structure and surface properties, as well as to explore the relationship between catalyst nature and catalytic performance. It is found that the addition of guanidine nitrate in the pyrolysis process of CNT with melamine significantly affects the structure, surface properties, and catalytic performance. The optimized N‐doped CNTs demonstrate steady‐state styrene production rates 1.56 and 1.60 times higher than those of the parent CNTs and the established nanodiamond, as well as 6.49 times the rate of commercially available K–Fe catalyst without compromising the selectivity to styrene. The much superior catalytic performance in metal‐free catalytic direct dehydrogenation can be ascribed to the CO group‐ and defect‐rich surface nature, the basic properties resulted from N‐doping, the larger surface area and pore volume, and smaller graphitic carbon crystallites. The fabricated novel N‐doped CNTs can be considered as a promising candidate for sustainable production of styrene through oxidant‐ and steam‐free direct dehydrogenation of ethylbenzene with energy‐saving and environmentally benign features. The developed defect‐formation strategy in this work can be used for preparation of other metal‐free carbocatalysts.