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[Display omitted] • A zwitterionic hydrogel was introduced for moisture-energy generation. • The polyelectrolyte changes were resisted through the salt-in effect. • The adsorption capacity of the hydrogel reached 3.0 g g−1 at 90% RH and 25 °C. • The device exhibiting an I sc of up to 945 μA cm−1 and a V oc of 0.802 V. Hygroscopic salt composite hydrogels (HSCHs) offer a promising solution for combating global water scarcity by harvesting atmospheric water. Importantly, this is aided by an interior water gradient that facilitates ion transport, which opens up opportunities for power generation. The current and potential outputs are restricted by inadequate water collection and excessive cross-link density. Herein, a novel zwitterionic nanocomposite conductive hydrogel (ZNCH) is introduced to resist polyelectrolyte changes by leveraging the salt-in effect of cationic and anionic functional groups. The poly-[2-(methacryloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide-based ZNCH endows the HSCH with an enhanced swelling property together with an improved water storage capacity. The adsorption capacity of water reaches 3.0 g g−1 after 10 h of operation at 25 °C and 90% RH. More importantly, ZNCH replaces H bonds with Li bonds under the Hofmeister effect, resulting in the generation of a substantial number of free H+ ions. These endow the ZNCH with highly efficient power generation performance, associating with a short-circuit current of up to 945 μA, a current density of 945 μA cm−1, and an open-circuit voltage of 0.802 V. This work motivates the improvement of materials and devices that convert energy from atmospheric water. [ABSTRACT FROM AUTHOR]

• Ultrahigh through-plane thermal conductivity achieved by continuous carbon fibers. • Thermal-induced and slant slicing-induced flexibility. • Leakage proof capacity from polymer skeleton and carbon fiber arrays. • Novel thermal management capacity from high through-plane thermal conductivity and heat absorbed during phase change. With the rapid development of micro-nano electronics, thermally conductive materials with remarkable through-plane thermal conductivity (κ ⊥) and great flexibility are greatly urgent to effective thermal management. The fillers with high thermal conductivity (TC) are commonly assembled to achieve this target. However, the imperfect contact between the joint fillers will lead to high thermal resistance (R), hindering thermal transport. Herein, we fabricated thermal interface materials (TIMs) with ultra-high κ ⊥ (up to 168.4 W m−1 K−1) and adjustable flexibility by the combination of highly thermally conductive carbon fiber bundles (CF) and polymer encapsulated phase change materials (PCMs). The alignment of consecutive CF guarantees the continuity of thermal paths, greatly facilitating thermal transport. While the slantly slicing technique and softening effect of PCMs beyond phase transition temperature lead to an attenuated compression stress (1.6 MPa@10% strain with a CF loading of 50 wt%). What's more, the latent heat absorbed by PCMs is also conducive to thermal management. Thus, during a CPU temperature-control experiment, the application of as-prepared TIMs manifests a temperature decline of 33.9 °C of CPU. This work opens a new perspective to fabricating TIMs with ultrahigh κ ⊥ and low compression stress (σ) by the combination of thermally induced flexible matrix and the slantly slicing technique of aligned CFs. [ABSTRACT FROM AUTHOR]

[Display omitted] • h-BN assembles into spherical aggregated BN (A-BN) assisted by the vortex flow. • The mechanism and operating conditions of A-BN formation are systematically studied. • A through-plane TC of 6.56 W/(mK) is achieved due to the formation of A-BN. • A-BN/AlN/SR composite demonstrates excellent heat dissipation performance as TIMs. Thermal interface materials (TIMs) with high thermal conductivity and good insulation properties are in high demand for thermal management systems. Platelet-like materials such as BN and graphene usually orient horizontally in polymer composites, causing minor Through-plane thermal conductivity (TC) enhancement. Herein, aggregated BN (A-BN)/AlN/silicone rubber (SR) composites with enhanced through-plane TC are fabricated assisted by vortex flow during the planetary centrifugation process. It is found that BN platelets assembled into A-BN with spherical AlN as cores based on concentric vortex. Due to the formation of spherical A-BN, through-plane TC of as-prepared composites with 40 wt% BN and 45 wt% AlN is as high as 6.56 W/(m·K) while it is only 4.62 W/(m·K) for composites without A-BN. Such high TC should mainly be attributed to the large-sized spherical BN interconnected structure which constructs an efficient thermally conductive path in the through-plane direction. The heat dissipation evaluation test also demonstrates the excellent performance of the A-BN/AlN/SR composite. This work provides a facile strategy to produce large-sized BN agglomerates and gives insights into the vortex flow during the planetary centrifugation process. [ABSTRACT FROM AUTHOR]