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Considering the significant threat of heat to electronic equipment and the heat dissipation problems existing in powerful systems, thermal management materials are in high demand. In conjunction with the increasing desire of dissipating heat and stabilizing temperature, high thermal conductivity and phase change latent heat are attracting more attention when designing thermal management material. This work proposes a strategy to combine phase change matrix and thermally conductive filler using freeze casting. The highest thermal conductivity reaches 23.1 W m-1 K-1 accompanied by 62 J g-1 phase change latent heat. Meanwhile, replacing ice with organic phase change material in freeze casting can result in an aligned structure. This discovery will pave a novel way for introducing thermal latent heat without abandoning the aligned structure.

Enabling efficient and durable charge storage under high sulfur loading and lean electrolyte remains a paramount challenge for Li-S battery technology to truly demonstrate its commercial viability. This work reports an amphoteric polymer binder, whose negatively and positively charged moieties allow for coregulation of both lithium cations and heteropolar lithium polysulfides through multiple intermolecular interactions. These interactions and the physical properties lead to simultaneously improved Li

The space within the interlayer of 2-dimensional (2D) nanosheets provides new and intriguing confined environments for molecular interactions. However, atomic level understanding of the adsorption mechanism of CO2 confined within the interlayer of 2D nanosheets is still limited. Herein, we present a comparative study of the adsorption mechanisms of CO2 confined within graphene–molybdenum disulfide (MoS2) nanosheets using density functional theory (DFT). A comprehensive analysis of CO2 adsorption energies (EAE) at various interlayer spacings of different multilayer structures comprising graphene/graphene (GrapheneB) and MoS2/MoS2 (MoS2B) bilayers as well as graphene/MoS2 (GMoS2) and MoS2/graphene (MoS2G) hybrids is performed to obtain the most stable adsorption configurations. It was found that 7.5 A and 8.5 A interlayer spacings are the most stable conformations for CO2 adsorption on the bilayer and hybrid structures, respectively. Adsorption energies of the multilayer structures decreased in the following trend: MoS2B > GrapheneB > MoS2G > GMoS2. By incorporating van der Waals (vdW) interactions between the CO2 molecule and the surfaces, we find that CO2 binds more strongly on these multilayer structures. Furthermore, there is a slight discrepancy in the binding energies of CO2 adsorption on the heterostructures (GMoS2, MoS2G) due to the modality of the atom arrangement (C–Mo–S–O and Mo–S–O–C) in both structures, indicating that conformational anisotropy determines to a certain degree its CO2 adsorption energy. Meanwhile, Bader charge analysis shows that the interaction between CO2 and these surfaces causes charge transfer and redistributions. By contrast, the density of states (DOS) plots show that CO2 physisorption does not have a substantial effect on the electronic properties of graphene and MoS2. In summary, the results obtained in this study could serve as useful guidance in the preparation of graphene–MoS2 nanosheets for the improved adsorption efficiency of CO2.

A density functional theory study was conducted to analyze CO2 adsorption on defective and non-defective MoS2 surfaces with or without nitrogen doping. The MoS2_1VS and MoS2_1VMo_3NS were found exhibiting outstanding adsorption activity and stability, which is linked to an enhanced electron charge on the surface in the presence of vacancies and N species that alters strength and type of interactions with CO2 molecules. Results showed the dissociative chemisorption of CO2 on the MoS2_1Vs and a significantly enhanced physisorption of CO2 on the MoS2_1VMo_3NS, which displays an adsorption energy of −1.818 eV compared with −0.139 eV of the pristine MoS2 surface. Meanwhile, the MoS2_1Vs exhibits an excellent selective adsorption of CO2 over N2 and H2O, with the highest adsorption ratio of 5.1 and 3.5, respectively. Partial dissociation of CO2 to CO over the MoS2_1Vs is also observed and attributed to increased covalent attractions at the vacant site, while the improved CO2 physisorption over the MoS2_1VMo_3NS is attributed to the enhanced electrostatic interactions at the vacancy site due to N doping. These findings are confirmed by the computed vibrational frequencies of CO2 bound on these surfaces. The N-doping enabled defect engineering of MoS2 is proved effective and enhanced selective adsorption of CO2.