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A hierarchical carbon material containing nanopores (micropores and mesopores) and micrometric sized capillaries (macropores) is produced using a combination of hard and soft templates. The hard template is a polypropylene (PP) cloth which decomposes during pyrolysis leaving a macroporous structure. The soft template is a cationic polyelectrolyte which stabilizes the resorcinol/formaldehyde (RF) resin porous structure during drying to give a nanoporous RF resin. The method produces a nanocomposite of the porous RF resin with an imbibed PP cloth. The composite is then pyrolyzed in a inert gas atmosphere to render a carbon material having macropores as well as micro/mesopores. The material exhibits both a large surface area (S_BET = 742 ± 2 m²/g) due to nanopores and goof fluid permeability due to micrometric sized pores. The macropores can be oriented during fabrication. The nanoporous surface can be used to support metal nanoparticles for fuel cell while the macropores allow easy flux of gas and liquids through the monolithic material.

Carbon-modified Ti${}^{3+}$ self-doped hierarchical porous titanium dioxides were synthesized by one-step soft chemical method. The contents of carbon and Ti${}^{3+}$ of the catalysts were tuned through a facile heat treatment. The prepared photocatalysts possess well-packed uniform macropores with the size of $\sim 200$nm, mesoporous structure with the pore size of 5.9–6.8nm, and the specific surface area of 50–200m²/g. The results illustrate the carbon combined with TiO₂ via the interfacial C$-$O$-$Ti bonds and the rich existence of Ti${}^{3+}$. The catalyst with 18wt.% carbon content exhibits a degradation ratio of crystal violet up to 97.5%. The enhanced photocatalysis is ascribed to the synergistic effect of carbon and Ti${}^{3+}$. The interfacial C$-$O$-$Ti bonds act as the pathway to transfer excited electrons and the Ti${}^{3+}$ can trap the electrons to hinder the recombination of electrons and holes.

In rechargeable lithium-sulfur (Li-S) batteries, the conductive carbon materials with high surface areas can greatly enhance the electrical conductivity of sulfur cathode, and metal oxides can restrain the dissolution of lithium polysulfides within the electrolyte through strong chemical bindings. The rational design of carbon-metal oxide nanocomposite cathodes has been considered as an effective solution to increase the sulfur utilization and improve cycling performance of Li-S batteries. Here, we summarize the recent progresses in the carbon-metal oxide composites for Li-S battery cathodes. Some insights are also offered on the future directions of carbon-metal oxide hybrid cathodes for high performance Li-S batteries.

In this paper, carbon particles with micro- and nano-particle size were synthesized through a hydrothermal reaction of glucose, namely C-1(123.1 nm), C-2(229.2 nm), C-3(335.1 nm), C-4(456.2 nm) and C-5(534.0 nm) with distinct sizes. We utilized five size carbon particles as individual fillers into the EHS matrix materials to prepare composite eutectic phase change materials (C/EHS PCMs) by melt blending technique. The impact of carbon particle size on the dispersion stability and thermal properties of Na₂SO₄⋅10H₂O–Na₂HPO₄⋅12H₂O (EHS) phase change materials was investigated. Scanning electron microscopy (SEM) and dynamic light scattering (DLS) analysis were done to analyze the diameters of carbon particles. The cryogenic-scanning electron microscopy (Cryo-SEM) analysis indicated that the carbon particles resulted in modification in the morphology of the EHS. The results of in situ X-ray diffraction (XRD) and Fourier-transformed infrared (FTIR) analysis showed only simple physical mixing between carbon particles and EHS. It is shown that adding 0.2 wt.% C-2 can decrease the supercooling degree of EHS to 1.5${}^{\circ }$C. The cyclic stability of C/EHS varies significantly depending on the size of carbon particles. The thermal conductivity of EHS increased by 42.1%, 39.9%, 14.4%, 19.5%, and 18.8% with the addition of C-1, C-2, C-3, C-4, and C-5, respectively, at a mass fraction of 0.2%. The results of differential scanning calorimetry reveal that the incorporation of C-1, C-2, C-3, and C-4 into EHS leads to an enhancement of latent heat. The latent heat capacity of EHS with 0.2 wt.% C-2 is 243.4 J⋅g${}^{-1}$, and after undergoing 500 cycles of solid-liquid phase transition, the latent heat remained above 200 J⋅g${}^{-1}$. Through the comprehensive analysis, the C-2/EHS composite phase change material holds significant potential for advancing building insulation and solar energy storage technologies.

As green anode materials with wide distribution, controllable cost, and diversified structure, carbon materials have received more attention. In this paper, iodine- and nitrogen-co-doped carbon flower materials were prepared. The flower-like structure of the material ensures the rapid diffusion of lithium ions, and the synergistic effect of iodine and nitrogen atoms improves the pore size distribution, the conductivity and the active sites of carbon materials realizing the high ion storage and the fast charge diffusion. As the anode material of lithium-ion batteries, the iodine- and nitrogen-co-doped carbon flower could have the capacitance of 410 mAh g${}^{-1}$ at the current density of 0.1 A g${}^{-1}$ after 150 cycles and 181 mAh g${}^{-1}$ at the high current density of 2.0 A g${}^{-1}$ after 1000 cycles. The results of electrochemical impedance spectroscopy, kinetics, and GITT show this material has fast charge transport kinetics and excellent rate performance.