Intelligent sensors have attracted substantial attention for various applications, including wearable electronics, artificial intelligence, healthcare monitoring, and human−machine interactions. However, there still remains a critical challenge in developing a multifunctional sensing system for complex signal detection and analysis in practical applications. Here, we develop a machine learning-combined flexible sensor for real-time tactile sensing and voice recognition through laser-induced graphitization. The intelligent sensor with a triboelectric layer can convert local pressure to an electrical signal through a contact electrification effect without external bias, which has a characteristic response behavior when exposed to various mechanical stimuli. With the special patterning design, a smart human−machine interaction controlling system composed of a digital arrayed touch panel is constructed to control electronic devices. Based on machine learning, the real-time monitoring and recognition of the changes of voice are achieved with high accuracy. The machine learning-empowered flexible sensor provides a promising platform for the development of flexible tactile sensing, real-time health detection, human−machine interaction, and intelligent wearable devices.

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Metallic micro/nano structures with special physicochemical properties have undergone rapid development owing to their broad applications in micromachines and microdevices. Ultrafast laser processing is generally accepted as an effective technology for functional structures manufacture, however, the controllable fabrication of specific metallic micro/nano structures remains a challenge. Here, this work proposes a novel strategy of laser induced transient solid‐liquid transition to fabricate unique structures. Through modulating the transient state of metal from solid to liquid phase using the initial pulse excitation, the subsequent ultrafast pulse‐induced recoil pressure can suppress the plasma emission and removal of liquid phase metals, resulting in the controllable fabrication of coffee‐ring structures. The solid‐liquid transition dynamics, which related with the transient reflectivity and plasma intensity, are revealed by established two temperature model coupled with molecular dynamics model. The coffee‐ring structure exhibits tunable structure color owing to various optical response, which can be used for color printing with large scale and high resolution. This work provides a promising strategy for fabricating functional micro/nano structures, which can greatly broaden the potential applications.

Hybrid supercapacitors use electric double‐layer capacitance and Faradaic pseudocapacitance as energy storage mechanisms. This type of supercapacitor is becoming a prime candidate for next‐generation energy storage devices, with advantages in terms of energy density, specific capacitance, and life cycle. However, reducing the electrode area and increasing the specific capacitance of hybrid supercapacitors remain challenging. In this study, a MoCl5 Precursor‐assisted Ultrafast Laser Carbonization (MPAULC) method to fabricate symmetric hybrid supercapacitors with improved capacitance and reduced size is proposed. The method uses an ultrafast laser to induce the formation of carbon/MoO3 composite with the assistance of the MoCl5 precursor. This ultrafast laser carbonization method exhibited high processing precision. The role of the precursor in laser processing is studied using time‐resolved imaging and temperature calculations. The specific area capacitance of the C/MoO3 hybrid supercapacitor is 11.85 mF cm−2, 9.2 times higher than that of the laser‐induced carbon supercapacitor without precursor. The MPAULC method provides a reliable pathway for fabricating miniaturized hybrid supercapacitors with carbon/metal oxide composite electrodes on polymer substrates.

Supercapacitors are widely used in electronic systems as energy storage devices. The fabrication of a miniaturized supercapacitor with high specific capacitance has attracted much attention in recent years. Here, we propose a new method to fabricate supercapacitors with a nanoscale electrode gap by using a femtosecond laser. The original femtosecond laser was converted to a nondiffraction Bessel light field with nanoscale beam width and microscale focal depth. Nanoscale processing precision was achieved by regulating the Bessel beam. We fabricated graphene supercapacitors with different electrode gap widths (varying from the microscale to the nanoscale) using this method. Supercapacitors fabricated by this method have advantages in both size miniaturization (electrode gap width down to ∼500 nm) and electrochemical performance improvement (a specific volumetric capacitance of 195 F/cm 3 ). This work demonstrates that the femtosecond laser Bessel beam processing method provides a reliable pathway to fabricate miniaturized supercapacitors with high specific capacitance and other nanoscale electronic devices.