In this study, we demonstrate rapid and facile supersonic cold spray deposition of Zn2SnO4 /SnO2/CNT nanocomposite supercapacitor electrodes with promising combinations of power and energy density. Cyclic voltammetry confirmed the capacitive behavior of the optimized electrode, with specific capacitance reaching 260 F·g–1 at a current density of 10 A·g–1. We attribute this high performance to the optimal combination of CNT (carbon nanotube; double-layer capacitance) and Zn2SnO4 /SnO2 (pseudocapacitance) properties. The mesoporous and accessible surface of the CNT significantly contributed to the excellent retention (approximately 93%) of the specific capacitance after 15000 galvanostatic charge/discharge cycles. In addition, the supercapacitor exhibited a remarkable energy density, electrochemical properties, and mechanical stability. The materials and approach presented here can enable cost-effective, efficient, and scalable production of high-performance supercapacitor electrodes.

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The demand for wearable, stretchable soft electronics for human–machine interface applications continues to grow given the potential of these devices in humanoid robotics, prosthetics, and health-monitoring devices. We demonstrate fabrication of multifunctional sensors with simultaneous temperature-, pressure-, proximity-, and strain (or bending)-sensing capabilities, combined with heating and UV-protection features. These multifunctional sensors are flexible, light, and transparent and are thus body-attachable. Silver nanowires are supersonically sprayed on a large-scale transparent and flexible roll-to-roll substrate. The junctions between nanowires are physically fused by a strong impact resulting from supersonic spraying, which promotes adhesion and efficient deposition of the nanowire network. Accordingly, nanowires are strongly interconnected, facilitating efficient propagation of electric signals through the fused nanowire network, which allows simultaneous operation of such sensors while maintaining significant transparency. These multifunctional sensors are mechanically durable and retain long-term stability. A theoretical discussion is provided to explain the respective mechanisms of heating and proximity, pressure, and strain sensing.

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Electrospun metal-plated nanofibers and supersonically sprayed nanowires were used to fabricate hybrid films exhibiting a superior low sheet resistance of 0.18 Ω sq−1, a transparency of 91.1%, and a figure-of-merit of 2.315 Ω−1.