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Constructing microsupercapacitors (MSCs) with an outstanding stretchability is urgent for wearable electronics, and an intrinsic biodegradability is also meaningful. Herein, laser‐induced graphene/NiO/Co3O4 (NiO/Co3O4/LIG) is in situ synthesized on a polyimide (PI) film during laser processing, then the electrodes are transferred to a biodegradable waterborne polyurethane (WPU) substrate to fabricate stretchable MSCs. Experimentally, the as‐prepared stretchable MSCs exhibit an excellent areal capacitance of 2.4 mF cm−2, high capacitance retention of 77.1% at 50% strain, and capacitance degradation of less than 19.8% after 1000 stretching cycles. These desirable properties are mainly attributed to the gradient structure of NiO/Co3O4/LIG, the synergistic effect of hybrid NiO/Co3O4 nanoparticles, and the intensive interface adhesion between the electrodes and WPU. Interestingly, the robust function of stretchable MSCs is further presented by using them to power a microsensor and assembling them with triboelectric nanogenerators to generate power from mechanical contact with skin, which makes the stretchable MSCs promising as a sustainable driving source for wearable electronics. [ABSTRACT FROM AUTHOR]

Simple and scalable manufacturing of flexible energy storage units with high electrochemical performance is essential for wearable electronic devices. Herein, a carbon cloth (CC) coated with Mo ion homo‐dispersed hydrogel ink is used as a precursor for laser scribing, during which laser‐induced graphene/MoO2 (LIG/MoO2) is in‐situ synthesized on the substrate. By regulating the surface topography and nanoparticle distribution, the as‐prepared LIG/MoO2‐CC electrode shows a network structure composed of multiple core‐shell fibers. Among them, the carbon‐fiber core phase provides strong mechanical stability, and the in‐situ growth shell of LIG/MoO2 ensures high electrochemical performance. Experimentally, the MSCs assembled by interdigital electrodes can deliver an areal capacitance of 81.8 mF cm−2 and areal energy density of 113.7 μWh cm−2 at a power density of 2.5 mW cm−2, placing them among the best performing LIG‐based MSCs. Through the series‐parallel structure design of electrodes, the output voltage and total capacitance of MSCs can be adjusted according to the demands of actual applications, presenting a huge potential for integration with other wearable electronics. [ABSTRACT FROM AUTHOR]

Latest advances have witnessed the laser scribing of various active materials from synthetic polymers to natural sources without masks, post‐treatment, or toxic substances. However, laser induced graphene (LIG) on renewable precursors usually requires flame‐retardant pretreatment and multistep pulsed or defocused irradiation. Laser scribing of silicon carbide (SiC) from polydimethylsiloxane (PDMS) is limited by its high transparency over a broad wavelength range. Here, a structural design strategy is adopted to solve these two dilemmas at the same time, that is, laser scribing of carbonized cloth/PDMS to prepare LIG/SiC composites. Natural cotton cloth is precarbonized and inserted in PDMS substrate to facilitate heat absorption for the in situ formation of SiC, while the soft PDMS attached to the carbonized cloth absorbs heat and isolates oxygen, enabling the conversion of amorphous carbon to LIG. Under these multifield coupling effects, a core–shell LIG/SiC electrode is formed on the carbonized cloth with tunable mass ratio, morphology, and graphene defects. Experimentally, the LIG/SiC pressure sensor exhibits a good sensitivity of 1.91 kPa−1 in the super‐wide sensing range of 0–226.7 kPa. By demonstrating different scenarios such as real‐time monitoring of large body movements, tiny pulses and heartbeats, the flexible pressure sensors hold great promise in wearable electronics. [ABSTRACT FROM AUTHOR]