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Graphical abstract Highlights • Interface-facilitated synthesis of graphene-like carbon nanosheets. • P123 serves a dual function of structure-directing agent and carbon precursor. • Carbon nanosheets can self-organize into film with high uniformity. Abstract A novel interface-facilitated synthesis of graphene-like carbon nanosheets from P123 is reported. The morphology and structure of the carbon nanosheets were characterized though FESEM, TEM, AFM, XRD, Raman and FTIR. The formation mechanism of the graphene-like carbon nanosheets is proposed. P123 serves a dual function of structure-directing agent and carbon precursor, which first assembles at the toluene-HCl interface and then is in situ carbonized to carbon nanosheets. This process shows several advantages such as mild condition, simple procedure and low cost. In addition, the obtained carbon nanosheets can be effectively confined at the interface and self-organize into film with high uniformity. [ABSTRACT FROM AUTHOR]

• Hierarchical Co-embedded porous carbon microspheres were controllably synthesized. • The Co-based catalyst showed superior performance beyond noble-metal-based catalysts. • The partially uncovered and totally in-built Co species were likely the active sites. The direct pyrolysis of metal organic frameworks (MOFs) has recently provided an effective method to prepare various metal-incorporated composite carbon materials. In this work, hierarchical Co-embedded N-doped porous carbon microspheres were synthesized by controlled pyrolysis of bimetallic Zn-Co Prussian blue analogues (PBAs), in which the metallic Zn component served as thermally removable template and ligand [Co(CN) 6 ]3− served as both Co and N sources. When devoted to catalyzing the reduction of 4-nitrophenol (4-NPh) into 4-aminophenol (4-APh), the optimized catalyst exhibited a large apparent rate constant of 1.35 min−1 and high turnover frequency (TOF) of 0.0204 s−1, which was superior to the majority of noble-metal-based catalysts. Besides, a home-made continuous flow catalysis system was readily constructed. Control experiments confirmed that both partially uncovered and totally in-built active metallic Co species acted as catalytically active sites. This work might provide a further understanding of the identification of active sites within metal-incorporated carbon-based catalysts. [ABSTRACT FROM AUTHOR]

N-doped carbon possesses the advantages of electronic modification and immobilization of metal nanoparticles. Hence, N-doped carbon-based metal catalysts have received extensive attention. This study prepared uniformly dispersed Ni nanoparticles (24.0 wt%) on porous N-doped carbon, which was fabricated via the high temperature pyrolysis of nitrogen-rich ZnNi MOFs with 1H-1,2,3-triazole as the ligand. The 1H-1,2,3-triazole as a high energy ligand could volatilize violently to form a N-doped macroporous carbon-based structure. Zn acted as a fence and prevented the accumulation of Ni during the pyrolysis of ZnNi MOFs. The synergistic effect from the abundant porous structure together with uniformly dispersed Ni nanoparticles proves the excellent catalytic activity toward the hydrogenation of dicyclopentadiene, showing 100% DCPD conversion and >99% THDCPD selectivity. Uniformly dispersed Ni nanocatalyst on porous N-doped carbon which was fabricated through increasing the pyrolysis temperature of ZnNi MOFs, shows enhanced catalytic activity toward the hydrogenation of DCPD. [Display omitted] [ABSTRACT FROM AUTHOR]

New shape‐stabilized paraffin/porous carbon materials derived from metal organic gel (cMOG)/boron nitride (BN) composites were prepared by the impregnation method. In the composites, paraffin was used as phase change material, while cMOG as a supporting and loading large paraffin content in the pores owing to high specific surface area and BN employed to enhance the thermal conductivity. The scanning electron microscopy images showed better filler–filler connectivity in BN/cMOG than the individual supporting materials. With the synergy of BN and cMOG, the thermal conductivity of BN/cMOG/PCM composites exhibited up to 232.1 % of pristine PCM and 82.3 % of binary BN/PCM composites at the same wt.‐% of BN. The latent heat as‐synthesized composite attains up to 163.1 J/g with up to 80 wt.‐% of paraffin retained in the composites without any leakage. In addition, the composites revealed enhanced heat transfer performance in both the solid and liquid states. Similarly, the XRD and FTIR analysis showed excellent chemical compatibility between paraffin and the supporting materials. In addition, the composite has high thermal stability, reduced supercooling extent, and better reliability after 200 times thermal cycling, which indicate a promising method for large‐scale thermal energy storage. Shape‐stabilized porous carbon materials derived from metal organic gel/BN/paraffin were prepared. They have enhanced heat transfer performance in both the solid and liquid phases and large energy storage capacity. [ABSTRACT FROM AUTHOR]

A systematic mesoporous N-doped carbons/myristic acid-stearic acid composite materials with improved thermal conductivity, energy storage density and shape stable performance were prepared by encapsulating myristic acid-stearic acids (MA-SA) eutectic mixture into porous carbon matrixes derived from two synthesis strategies. The effect of synthesis strategies and the N species present in porous carbons on the microstructure and thermal energy storage properties of composite phase change materials were studied by various characterization techniques. The results indicated that N-doped porous carbons derived from in situ (NPC) had maximum of up to 88 wt% PCM loading with a melting latent heat of 164.33 ± 0.29 kJ/kg, which was up to 45.69% higher than that of composite PCMs by post synthesis route (MGC/MA-SA). Factors, like pore characteristics, capillary force, surface tension and additional interaction with N species present in carbon matrix played vital roles for encapsulation of MA-SA to the pores of supporting materials. Notably, NPC/MA-SA composite materials exhibited excellent thermal conductivity, 117.65% higher than pristine PCM, while 74.59% for MGC/MA-SA. The content, homogeneous distribution and graphitic nature of N as well as the interconnected porous carbons improves the heat transfer pathways in the composite PCMs during phase change process. All the prepared samples were thermally and chemically compatible even after 100 times thermal cycling, confirming that the prepared composite materials were a promising candidates for thermal management system in a medium phase transition temperatures like domestic solar hot water supply and air-conditioning purposes. [ABSTRACT FROM AUTHOR]

Hierarchical and hollow nanostructures have recently attracted considerable attention because of their fantastic architectures and tunable property for facile lithium ion insertion and good cycling stability. In this study, a one-pot and unusual carving protocol is demonstrated for engineering hollow structures with a porous shell. Hierarchical TiO2 hollow spheres with nanosheet-assembled shells (TiO2 NHS) were synthesized by the sequestration between the titanium source and 2,2′-bipyridine-5,5′-dicarboxylic acid, and kinetically controlled etching in trifluoroacetic acid medium. In addition, annealing such porous nanostructures presents the advantage of imparting carbon-doped functional performance to its counterpart under different atmospheres. Such highly porous structures endow very large specifics surface area of 404 m2 g−1 and 336 m2 g−1 for the as-prepared and calcination under nitrogen gas. C/TiO2 NHS has high capacity of 204 mA h g−1 at 1 C and a reversible capacity of 105 mA h g−1 at a high rate of 20 C, and exhibits good cycling stability and superior rate capability as an anode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]