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Designing ultra‐light, green, and flexible films for efficient electromagnetic interference (EMI) shielding is crucial yet challenging. Herein, laminated Ti3C2Tx MXene nanosheets are prepared and impregnated into a delignified wood matrix to fabricate composite films. Through a facile drop‐casting and densification strategy, highly aligned cellulose fibers are used for regulating the stacking behavior of MXenes, and the MXenes are encapsulated and attached tightly to the cellulose chains through hydrogen bonds. A high MXene loading up to 32.5 wt.% can be realized, and the resultant MXene/wood film exhibits a tensile strength of 260.7 MPa. The EMI shielding effectiveness is calculated to be 55.5 dB (X‐band, 8.2–12.4 GHz), with a normalized surface‐specific shielding effectiveness of 2673.4 B cm2 g−1. Moreover, the superior electrical conductivity and structural robustness of the composite film give it pressure‐sensing properties and show high sensitivity for monitoring diverse human physiological movements. [ABSTRACT FROM AUTHOR]

Abstract ZIF-8 wrapped two-dimensional ZIF-L(Co) was prepared. By adjusting the Zn2+ concentration in precursor, ZIF-8 layer with different thickness was coated onto sheet-like ZIF-L. After carbonization, hierarchical porous carbon with CNTs wrapping was formed. Proper ZIF-8 coating would result in the porous carbon with relative high BET surface area, N content, electrical conductivity and proper pore size distribution; thus showing higher supercapacitive performance than that of carbonized ZIF-8 or carbonized ZIF-L. The highest specific capacitance is 274 F/g for carbonized composite materials compared to that of 220 F/g for carbonized ZIF-8 and 57 F/g for carbonized ZIF-L. Moreover, such composite sample (CZ-6) showed high stability and the energy density reached 6.99 W h/kg at a power density of 0.262 kW/k, which is better than most of other ZIF-based porous carbon reported before. Graphical abstract Image 1 Highlights • ZIF-8 wrapped Co-ZIF-L was synthesized and carbonized into core-shell carbon. • The core-shell structure combined the merits of carbonized ZIF-8 and ZIF-L. • ZIF-L could avoid the agglomeration of ZIF-8 and help the graphitization of carbon. • Carbonized ZIF-L@ZIF-8 shows the highest specific capacitance of 274 F/g. [ABSTRACT FROM AUTHOR]

Because of multi-valence state of molybdenum (Mo), MoO 3 @MoO 2 heterojunction anchored on two dimensional (2D) g-C 3 N 4 nanosheets is created by calcining ammonium heptamolybdate with urea in a muffle furnace. The 2D porous structure of g-C 3 N 4 provides abundant active sites for lithium-ion storage, and it helps enhance the electrical conductivity and relieve large volume expansion effect during the discharge/charge process. The MoO 3 @MoO 2 heterojunction can accelerate the Li+/e- transfer, further improving sluggish charge transport kinetics and supplying high pseudocapacitive. Therefore, the resulting MoO 3 @MoO 2 heterojunction on g-C 3 N 4 electrode delivers a high capacity of 992 mAh g−1 0.5 A g−1 after 100 cycles and excellent rate performance. It still shows stable cycling performance when assembled into a full lithium-ion battery. • MoO 3 @MoO 2 heterojunction are anchored on two dimensional g-C 3 N 4. • g-C 3 N 4 provides abundant active sites and relieves large volume expansion effect. • MoO 3 @MoO 2 heterojunction could accelerate the Li+/e– transfer. • MoOx-UCN electrode shows excellent lithium-ion storage and rate performance. [ABSTRACT FROM AUTHOR]