Bencheikh, YasminaHarnois, MaximeJijie, RoxanaAddad, AhmedRoussel, PascalSzunerits, SabineHadjersi, ToufikAbaidia, Seddik-El-HakBoukherroub, Rabah2021-04-042021-04-0420190013-4686https://www.sciencedirect.com/science/article/abs/pii/S0013468619307698#!DOI: 10.1016/j.electacta.2019.04.083https://dspace.univ-boumerdes.dz/handle/123456789/6746The continuous increase of small electronic devices calls for small energy storage components, commonly known as micro-supercapacitors, that can ensure autonomous operation of these devices. In this work, we propose a simple and straightforward method to achieve high energy and power densities of a silicon-based micro-supercapacitor, consisting of silicon nanowires decorated with ruthenium nanoparticles (Ru/Si NWs). The Si NWs are obtained through the common vapor-liquid-solid (VLS) growth mechanism, while a simple electroless process is used to deposit Ru nanoparticles. While silicon nanostructuration allows to increase the surface area, coating with Ru NPs introduces a pseudocapacitance necessary to attain high energy and power densities. The Ru/Si NWs micro-supercapacitor exhibits a specific capacitance of 36.25 mF cm−2 at a current density of 1 mA cm−2 in a neutral Na2SO4 electrolyte and a high stability over 25 000 cycles under galvanostatic charge-discharge at 1 mA cm−2. A solid state supercapacitor is then fabricated with symmetric electrodes separated by a polyvinyl alcohol/sulfuric acid electrolyte. The device displays a specific capacitance of ∼18 mF cm−2 at a current density of 1 mA cm−2 and a specific power density 0.5 mW cm−2. This solid-state nanowire device also exhibits a good stability over 10 000 galvanostatic charge-discharge cyclesenMicro-supercapacitorsSilicon nanowiresRuthenium nanoparticlesSolid-state devicesArticle