Flexible tactile sensors are garnering substantial interest for various promising applications, including artificial intelligence, prosthetics, healthcare monitoring, and human–machine interactions (HMI). However, it still remains a critical challenge in developing high‐resolution tactile sensors without involving high‐cost and complicated manufacturing processes. Herein, a flexible high‐resolution triboelectric sensing array (TSA) for self‐powered real‐time tactile sensing is developed through a facile, mask‐free, high‐efficient, and environmentally friendly laser direct writing technique. A 16 × 16 pixelated TSA with a resolution of 8 dpi based on patterned laser‐induced graphene (LIG) electrodes (7 Ω sq−1) is fabricated by the complementary intersection overlapping between upper and lower aligned semicircular electrode arrays. With the especially patterning design, the complexity of TSA and the number of data channels is reduced. Meanwhile, the TSA platform exhibits excellent durability and synchronicity and enables the achievement of real‐time visualization of multipoint touch, sliding, and tracking motion trajectory without power consumption. Furthermore, a smart wireless controlled HMI system, composed of a 9‐digital arrayed touch panel based on a LIG‐patterned triboelectric nanogenerator, is constructed to control personal electronics wirelessly. Consequently, the self‐powered TSA as a promising platform demonstrates great potential for an active real‐time tactile sensing system, wireless controlled HMI, security identification and, many others.

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A phase change material (PCM) essentially making up hexadecyl acrylate-grafted graphene (HDA-g-GN) was fabricated via a solvent-free Diels–Alder (DA) reaction. The novel material exhibits multiresponsive, enhanced thermal and electrical conductivities and valid thermal enthalpy. In addition, the optimum DA reaction conditions were explored. A variety of characterization techniques were used to study the thermal, crystalline, and structural properties of HDA-g-GN. The melting and crystallizing enthalpies of HDA-g-GN were as high as 57 and 55 J/g, respectively. Furthermore, the melting and freezing points of HDA-g-GN were 29.5 and 32.7 °C, respectively. The thermal conductivity of HDA-g-GN reached 3.957 W/(m K), which is well above that of HDA itself and the previously reported PCMs. HDA-g-GN exhibited an excellent electric conductivity of 219 S/m. Compared to HDA, the crystalline activation energy of HDA-g-GN decreased from 397 to 278 kJ/mol (Kissinger model) and 373 to 259 kJ/mol (Ozawa model). Moreover, HDA-g-GN exhibited excellent thermal stability, shape stability, and thermal reliability. More importantly, HDA-g-GN can be employed to realize high-performance light-to-thermal and electron-to-thermal energy conversion and storage, which provides wide application prospects in energy-saving buildings, battery thermal management system, bioimaging, biomedical devices, as well as real-time and time-resolved applications.

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The applications of phase change materials (PCMs) in some practical circumstances are currently limited due to the constant strong rigidity, poor thermal conductivity, and low photoabsorption property. Therefore, the design of flexibility-enhanced, highly efficient PCMs is greatly desirable and challenging. In this work, novel PCM composites (CPmG-x) with stable forms and thermally induced flexibility were successfully prepared by grafting the comblike poly-(hexadecyl acrylate) polymer (PA16, phase change working substance) onto a cellulose support by atom transfer radical polymerization (ATRP). Modified graphene (GN16) was incorporated into the synthesized material to enhance its enthalpy, thermal conductivity, and physical strength. The prepared CPmG-x composites exhibit excellent softness and flexibility after phase transition of PA16. The addition of GN16 increases the thermal conductivity and enthalpy of CPmG-x materials to 1.32 W m −1 K −1 (9 wt % GN16) and 103 J g −1 (5 wt % GN16), respectively. Assessments of the solar-to-thermal energy conversion and storage efficiencies indicate that CPmG-x composites possess great potential for use in thermal energy management applications and solar energy collection systems.

The study has fabricated a TEG with enhanced solar–thermal–electric energy conversion and expands the application of PCMs on TEG and promises a new potential application in advanced energy-related devices, waste heat reuse and other fields.

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