Latent heat thermal energy storage (LHTES) uses phase change materials (PCMs) to store and release heat, and can effectively address the mismatch between energy supply and demand. However, it suffers from low thermal conductivity and the leakage problem. One of the solutions is integrating porous supports and PCMs to fabricate shape-stabilized phase change materials (ss-PCMs). The phase change heat transfer in porous ss-PCMs is of fundamental importance for determining thermalfluidic behaviours and evaluating LHTES system performance. This paper reviews the Highlights: 1. The recent advances in experimental and numerical investigations on phase change heat transfer in porous ss-PCMs are reviewed. 2. Paraffin and metal foams are the mostly used PCM and porous support respectively in the experimental studies. 3. Compared to REV-scale simulation, the pore-scale simulation can provide extra flow and heat transfer characteristics in pores. 4. There exists a research gap between phase change heat transfer and material preparation.

Two dimensional (2D) bimetal–MOFs (CoxFe–MOF) nanosheets have been successfully synthesized, which can simultaneously meet the requirement of both OER and NRR, thus providing the potential for coupling both OER and NRR in a full-cell configuration.

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Exploration of sustainable electrocatalysts toward oxygen reduction reaction (ORR) with high catalytic activity remains a key challenge in the development of metal-air batteries and fuel cells. In this work, a hybrid electrocatalyst composed of cobalt (Co/CoO) nanoparticles encapsulated in Co/N-doped mesoporous graphene (Co/CoO@Co/N-graphene) is reported for efficient ORR catalysis. The catalyst is rationally designed and synthesized via a facile combination of spontaneous one-pot polymerization of dopamine in the presence of graphene oxide (GO) and Co ions and the subsequent carbonization process. The morphology, doping nature and ORR activity of the as-prepared catalyst are systematically investigated. It is found that there are abundant Co/N active sites and Co/CoO nanoparticles in this hybrid catalyst, leading to a synergistic enhancement effect for improved ORR activity. In an alkaline environment, this Co/CoO@Co/N-graphene catalyst displays Pt/C-comparable ORR activity in terms of half-wave potential and four-electron reduction selectivity, and higher limiting current density, better methanol tolerant ability and long-term durability. When being evaluated in a Zn-air battery, it demonstrates superior performance to the commercial Pt/C catalyst.

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A carbon-based solid acid catalyst was prepared by sulfonation of partially carbonized peanut shell, and characterized by SEM, EDS, BET analysis, FTIR spectroscopy, NH 3 TPD, and TGA. The analytic results indicate that sulfonated peanut shell catalyst has an amorphous porous structure with a high acid capacity and good thermal stability and exhibits better catalytic activity for the glycerol etherification reaction than cation-exchange resin. With a molar ratio of isobutylene to glycerol of 4:1, a catalyst-to-glycerol mass ratio of 6 wt %, a reaction temperature of 343 K, and a reaction time of 2 h, glycerol was completely transformed into a mixture of glycerol ethers including mono-tert-butylglycerols (MTBGs), di-tert-butylglycerols (DTBGs), and tri-tert-butylglycerol (TTBG), and the selectivity toward the sum of the desired DTBGs and TTBG of 92.1% was obtained. Moreover, excellent reusability of the catalyst was also confirmed by repeated experiments.

Regulating the electronic states of single atomic sites around the Fermi level remains a major concern for boosting the electrocatalytic oxygen reduction reaction (ORR). Herein, a Fe d‐orbital splitting manner modulation strategy by constructing axial coordination on FeN4 sites is presented. Experimental investigations and theoretical calculations reveal that the axial tractions induce the distortion of square‐planar field (FeN4 SP), up to the quasi‐octahedral coordination (FeN4O1 OCquasi), thus leading to the electron rearrangement with a diluted spin polarization. The declined population of unpaired electrons in dz2, dxz and dyz states engenders a moderate adsorption of ORR intermediates, thereby reinforcing the intrinsic reaction activity. In situ infrared spectroscopy further demonstrates that the reordering of d‐orbital splitting and occupation facilitates the desorption of *OH. The FeN4O1 OCquasi exhibits a dramatic improvement of kinetic current density and turnover frequency, which are fivefold and tenfold higher than those of FeN4 SP. This work presents a novel understanding on improving the electrocatalytic performance through the orbital‐scale manipulation.

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