EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

The bottom-up synthesis of silicon nanowires (SiNWs) has traditionally been associated with challenging reaction conditions such as high temperatures, sub-atmospheric pressures and long reaction times. In this work, we have developed a bottom-up synthesis method for SiNWs at temperatures as low as 380 °C, using atmospheric pressures and reaction times as short as 60 seconds. These favourable reaction conditions enable the rapid synthesis of SiNWs in a glassware-based system, which significantly reduces the cost of synthesis. SiNW growth proceeds via the vapour-liquid-solid (VLS) mechanism using an air-stable silicon precursor (phenylsilane). We demonstrate controllability over NW diameter (<150nm) and mass loading by tailoring reaction times and temperatures. We show the versatility of this method for NW growth on various different substrates such as stainless steel foil, glass and high surface area substrates like fiberglass wool, stainless steel sponge and sodium chloride powder. Furthermore, we show the scalability of this approach by producing 1g of SiNWs per reaction when sodium chloride powder is used as the growth substrate.