Non‐contact mode triboelectric nanogenerators effectively avoid physical contact between two triboelectric materials and achieve long‐term reliable operation, providing broad application prospects in the field of self‐powered sensing. However, the low surface charge density of triboelectric materials restricts application of contactless sensing. Herein, by controlling Rayleigh Instability deformation of the spinning jet and vapor‐induced phase separation during electrostatic spinning, a polyvinylidene fluoride@Mxene (Ti3C2Tx) composite film with spheres multiple physical network structures is prepared and utilized as the triboelectric material of a self‐powered contactless sensor. The structure of the composite film and high conductivity of Ti3C2Tx provide triboelectric materials with high output performance (charge output and power output up to 128 µC m–2 and 200 µW cm–2 at 2 Hz) and high output stability. The self‐powered contactless sensor shows excellent speed sensitivity (1.175 Vs m–1). Additionally, it could accurately identify the motion states such as running (55 mV), jumping (105 mV), and walking (40 mV) within the range of 70 cm, and present the signals in different pop forms. This work lays a solid foundation for the development and application of high‐performance triboelectric materials, and has guiding significance for the research of self‐powered contactless sensing.

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Gas-sensitive materials are capable of dynamic identification and content monitoring of specific gases in the environment, and their applications in the field of gas sensing are promising. However, weak adsorption properties are the main challenge limiting the application of gas-sensitive materials. A highly adsorbent gas-sensitive cellulose nanofibril (CNF)-based triboelectric material with a layered structure is prepared here and it is applied to self-powered gas sensing. The layered structure of the triethoxy-1H,1H,2H,2H-tridecafluoro-n-octylsilane cellulose nanofiber (PFOTES-CNF)-based gas-sensitive material further enhances the adsorption of the material due to electrostatic adsorption in the electrostatic field induced by triboelectricity. It is found that the ammonia-sensitive material obtained by loading Ti 3 C 2 T x in PFOTES-CNF has a fast response/recovery (12/14 s), high sensitivity response (V air /V gas = 2.1), high selectivity response (37.6%), and low detection limit (10 ppm) for 100 ppm of ammonia gas. In addition, the ammonia-sensitive CNF-based triboelectric material can accurately identify NH 3 concentration changes in the range of 10-120 ppm and transmit the signal wirelessly to the user interface, facilitating real-time online monitoring of NH 3 in the environment. A novel strategy is provided here for designing and preparing high-performance gas-sensitive composites and the analysis of self-powered gas sensing is guided.

advanced materials with natural hierarchical structures have attracted considerable attention from researchers. [18][19][20][21][22][23][24] As an inexhaustible and sustainable resource, biomass materials show advantages in the development of highperformance structural materials due to their special hierarchical and porous structure. [25][26][27][28][29] The highly ordered hierarchical structure provides strong mechanical support for plant growth and promotes the vertical transportation of nutrients. The natural pore structure provides a channel for the exchange of material between adjacent cells and improves the energy storage efficiency of plants. [30,31] Inspired by this interesting organizational structure, researchers have developed composite advanced materials based on natural cellulose scaffolds, which is attracting attention in many fields such as energy storage, smart wearable electronics, [32][33][34] especially in the field of distributed micro-nano energy harvesting due to its special structure and excellent performance. [31,35] However, most bio-based composite materials still suffer from high-temperature decomposition, low-temperature brittleness, and even material decomposition, which severely limits their expansion and application in polar exploration, aerospace, and other extreme conditions. Therefore, it is still a great challenge to develop triboelectric functional materials with high efficiency, environmental stability, and rich sensing types.Compared with other biomass materials, bamboo, as a natural composite material, has a special functional gradient, in which the main components include lignin and cellulose. [36] In bamboo, fiber cells with various orientations composed of cellulose transport sufficient nutrients for the growth of lignin, while lignin provides adhesion and physical defense for the growth of fiber cells. Inspired by the "mutual benefit and winwin" model of natural bamboo, this research reports a simple and mild "three-step" strategy to the in situ growth of polyaniline (PANI) in bulk bamboo-derived cellulose scaffolds to construct hierarchical porous Bamboo/PANI triboelectric materials (BPTM) with continuous conductive pathways. The hierarchical porous cellulose scaffold constructed in this work enables abundant nucleation sites for the growth of PANI without complicated processes. Additionally, the hierarchical porous structure derived from natural bamboo allows the triboelectric charge to be distributed not only on the contact surface but also Synthetic polymer materials such as paraformaldehyde and polyamides are widely used in the field of energy engineering. However, they pose a challenge to environmental sustainability because they are derived from petrochemicals that are non-renewable and difficult to degrade in the natural environment. The development of high-performance natural alternatives is clearly emerging as a promising mitigation option. Inspired by natural bamboo, this research reports a "three-step" strategy for the large-scale production of triboelectric ...

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