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The active sites of inexpensive transition metal electrocatalysts are sparse and singular, thus high‐entropy alloys composed of non‐precious metals have attracted considerable attention due to their multi‐component synergistic effects. However, the facile synthesis of high‐entropy alloy composites remains a challenge. Herein, we report a "one‐stone, two‐birds" method utilizing zinc (Zn)‐rich metal–organic frameworks as precursors, by virtue of the low boiling point of Zn (907 °C) and its high volatility in alloys, high‐entropy alloy carbon nanocomposite with a layered pore structure was ultimately synthesized. The experimental results demonstrate that the volatilization of zinc can prevent metal agglomeration and contribute to the formation of uniformly dispersed high‐entropy alloy nanoparticles at slower pyrolysis and cooling rates. Simultaneously, the volatilization of Zn plays a crucial role in creating the hierarchically porous structure. Compared to the zinc‐free HEA/NC‐1, the HEA/NC‐5 derived from the precursor containing 0.8 Zn exhibit massive micropores and mesopores. The resulting nanocomposites represent a synergistic effect between highly dispersed metal catalytic centers and hierarchical adsorption sites, thus achieving excellent electrocatalytic oxygen reduction performance with low catalyst loading compared to commercial Pt/C. This convenient zinc‐rich precursor method can be extended to the production of more high‐entropy alloys and various application fields. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) with remarkable latent heat storage/release capacity have demonstrated prominent advantages in energy conservation and efficient thermal management. Nevertheless, simultaneously achieving high thermal energy storage capacity, excellent toughness, and flexibility in PCMs is a significant challenge for programmable deformations when used in complex environmental scenarios. A flexible PCM is reported with programmable deformation constructed through a three‐dimensional (3D) dynamic cross‐linked network. This approach has culminated in the development of homogeneously cross‐linked and self‐supporting polyurethane‐based solid‐solid PCM with graphene enhancement, which exhibits exceptional properties of high latent heat storage/release capacity (∆Hm = 105.3 J g−1, ∆Hc = 105.0 J g−1), high toughness (ε = 1543%, σ = 19.2 MPa), excellent flexibility, and shape memory behavior (Rr = 90.3%). Notably, when subjected to photothermal stimulation, it can lift objects weighing more than 2620 times their weight, presenting a working density of 1330 kJ m−3. This flexible PCM, which simultaneously possesses a high latent capacity and photothermal‐driven performance, opens a new pathway for artificial muscles or soft robots with the requirements for energy conservation and thermal management in complex scenarios. [ABSTRACT FROM AUTHOR]