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Phase change materials (PCMs) have high energy storage density and stable phase transition temperature, and are one of the most promising thermal storage and management materials. However, the PCMs' shape instability, poor light absorption, low electrical and thermal conductivity seriously hinder their multi-functional application. Herein, a three-dimensional carbon aerogel with grid structure, large porosity, and hierarchical porous structure was prepared from resource-rich plant straw for supporting PCMs. Polyethylene glycol (PEG) as thermal energy guest was encapsulated into carbon aerogel by simple vacuum impregnation. The obtained PEG/carbon aerogel composites show high loading rate of PCMs（＞97%), high thermal storage density (＞185 J g−1), stable shape, and effective solar/electro-thermal conversion. The grid structure carbon aerogel as efficient thermal and electron transfer pathways guarantee effective solar/electro-thermal conversion of composites. PEG encapsulated in each lattice as a thermal functional unit realizes the thermal storage and management. Especially, grid-structure composites realized fast and uniform electro-thermal conversion and storage under low voltage. This work provides a feasible, economic, and large-scale preparation strategy for the multi-functional PCMs. The multi-functional composites have broad application prospects in solar energy capture and storage, waste power recycling, building energy saving, smart thermal management and so on. [Display omitted] [ABSTRACT FROM AUTHOR]

The limited light absorption, low thermal conductivity, and poor shape stability restrict the widespread application of organic phase change materials (PCMs). Herein, carbon foam (CF) with the light, inter-connective porous, and high-strength was developed based on the phenolic resin to encapsulate organic PCMs, and multi-walled carbon nanotubes (MWCNTs) were added to improve the compressive strength and light absorption at the same time. Then, the polyethylene glycol (PEG) was encapsulated in the CF/MWCNTs composite via a vacuum impregnation method. The modified CF composite could act as an efficient heat transfer channel to improve the thermal conductivity and light-thermal conversion efficiency of PEG. As a result, the PEG/CF composites displayed a high latent enthalpy (156.3 J/g to 170.9 J/g) and an excellent light-thermal conversion efficiency (61%–74%). Furthermore, the PEG/CF 10 exhibited the highest thermal conductivity of 0.68 W/(m∙K), which is about 2.24 times higher than that of pure PEG. The as-prepared PEG/CF composites with mechanical strength and thermal stability could exhibit great potential in solar energy utilization, building energy conservation, and waste heat recovery. [Display omitted] • A phenolic resin carbon foam modified by MWCNTs has been first designed by a simple template method. • The modified carbon foam with inter-connective porous act as a good supporting material to encapsulate organic PCMs. • PEG/CF composites displayed an enhanced thermal conductivity and light-thermal conversion efficiency. • The light-thermal conversion and storage mechanism has been investigated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co/Fe co-doped ZIF-8 derived porous carbon for CDI removal of Cu2+ ions. • A stable carbon cage encapsulated a porous carbon structure. • CoFe-NC has better selectivity for Cu2+ ions. • CoFe-NC shows higher electrosorption capacity in application of CDI. Due to a threat to human life from heavy metal ions pollution, unprecedented interest has been gained in the development of water purification technologies. Here, we explore another new approach to exploit a prospective carbon material for removing copper ions from aqueous solution based on rapid and easy capacitive deionization (CDI). Reasonable carbon materials modification with ideal composition and improved morphological structure is essential to additionally optimize the capabilities of CDI. We prepared a nitrogen-rich hierarchically porous carbon composites (CoFe-NC) with uniform cobalt (Co) and iron (Fe) doped metal in carbon skeleton by a simple impregnation and pyrolysis method, derived from zeolitic imidazolate framework-8, to use as highly effective CDI electrode for copper ions removal. The addition of Fe can facilitate the uniform dispersion of metals, and enable the formation of a stable carbon cage after pyrolysis. It can sufficiently expose active sites of the electrode materials and promote interfacial charge transfer, thus improving CDI electrosorption efficiency. CoFe-NC composites electrode can achieve outstanding deionization capacity (91.31 mg g−1) in 25 mg L−1 CuSO 4 solution. The carbon cage structure of CoFe-NC not only prevents aggregation of metals and avoids destruction of rich multistage pore system by pyrolysis, but also induces a faster ions transport rate. In addition, density functional theory calculations demonstrated that the co-doping of Co and Fe can remarkably increase the adsorption energies of Cu2+ ions, leading to excellent selectivity, which indicates that CoFe-NC composites can be a desired CDI electrode material. [ABSTRACT FROM AUTHOR]

• Synergistic electrosorption of HBC bilayers and MoS 2 for Cu2+ complexation. • HBC shows excellent structural stability before and after MoS 2 loading. • High selective ion removal effect is still achieved in the presence of complex ions. • Used as an electrode in capacitive deionization technology. Capacitive deionization has been considered as a promising wastewater treatment technology because of its low-cost and highly efficient. Herein, we prepared hollow bowl-type carbon materials loaded with molybdenum sulfide (HBC-MoS 2) composites and fabricated it as an innovative electrode material to remove Cu2+ in a multi-ion coexistence system. With the synergistic effect of electric double layer (EDL) and complexation between MoS 2 and Cu2+, the HBC-MoS 2 -0.02 electrode achieved effective removal of copper ions from low concentration wastewater (25 mg/L) and high electrosorption capacity of 28.97 mg g−1 at 1.0 V. Even in the presence of competing ions (Na+/Zn2+/Cu2+), the HBC-MoS 2 -0.02 electrode still can effectively remove Cu2+ with a final adsorption capacity of 28 mg g−1, showing its superiority. The mechanism of Cu2+ removal by HBC-MoS 2 is mainly due to the synergistic effect of EDL and complexation. [ABSTRACT FROM AUTHOR]