Solution-phase synthesis of single-crystal Cu3Si nanowire arrays on diverse substrates with dual functions as high-performance field emitters and efficient anti-reflective layers

Abstract

There is strong and growing interest in applying metal silicide nanowires as building blocks for a new class of silicide-based applications, including spintronics, nano-scale interconnects, thermoelectronics, and anti-reflective coating materials. Solution-phase environments provide versatile materials chemistry as well as significantly lower production costs compared to gas-phase synthesis. However, solution-phase synthesis of silicide nanowires remains challenging due to the lack of fundamental understanding of silicidation reactions. In this study, single-crystalline Cu3Si nanowire arrays were synthesized in an organic solvent. Self-catalyzed, dense single-crystalline Cu3Si nanowire arrays were synthesized by thermal decomposition of monophenylsilane in the presence of copper films or copper substrates at 420 to 475 °C and 10.3 MPa in supercritical benzene. The solution-grown Cu3Si nanowire arrays serve dual functions as field emitters and anti-reflective layers, which are reported on copper silicide materials for the first time. Cu3Si nanowires exhibit superior field-emission properties, with a turn-on-voltage as low as 1.16 V μm(-1), an emission current density of 8 mA cm(-2) at 4.9 V μm(-1), and a field enhancement factor (β) of 1500. Cu3Si nanowire arrays appear black with optical absorption less than 5% between 400 and 800 nm with minimal reflectance, serving as highly efficient anti-reflective layers. Moreover, the Cu3Si nanowires could be grown on either rigid or flexible substrates (PI). This study shows that solution-phase silicide reactions are adaptable for high-quality silicide nanowire growth and demonstrates their promise towards fabrication of metal silicide-based devices.

Spatially Correlated, Single Nanomaterial-Level Structural and Optical Profiling of Cu-Doped ZnO Nanorods Synthesized via Multifunctional Silicides

“…The bright-field optical image in Figure 1 A and SEM panels in Figure 1 B display low- and high-magnification views, respectively, of the as-synthesized Cu 3 Si NBs. The Cu 3 Si NBs on Si(100) were aligned in two specific crystal directions along [011] and [01-1] as previously reported [ 34 , 35 ], consistent with the underlying Si atom arrangement. The Cu 3 Si NBs shown in Figure 1 are approximately 750–800 nm in diameter and 11–14 μm in length.…”

“…The bottommost diffraction panel in Figure 3 A is from Cu 3 Si NBs self-assembled along the two preferential growth directions on Si(100). The peak appearing at 45.5° is indicative of Cu 3 Si (120)/(210) and the other peaks present are from Si [ 34 , 35 ].…”

High density and patternable growth of silicon, germanium and alloyed SiGe nanowires by a rapid anneal protocol

“…Silicon and germanium nanowires (NW) are an important material set that have found significant application in photovoltaic, semiconductor, battery and biomedical devices. [1][2][3][4][5][6][7][8] The most common growth protocol for Si and Ge NWs is by vapourliquid-solid (VLS), [9][10][11][12] or vapour-solid-solid (VSS) [13][14][15][16] mechanisms achieved using chemical vapour deposition (CVD), [17][18][19] molecular beam epitaxy (MBE) 20 or laser ablation. 21 More recently, solution based methods where NWs are nucleated and grown in supercritical fluids (SCF) 22,23 or high boiling point solvents (HBS) have proved attractive for high density growth directly from substrates [24][25][26][27][28][29][30] The HBS and SCF methods also take advantage of the solvents as the carrier media for organometallic precursors in liquid form negating the requirement for silane or germane gases that are highly reactive.…”

Efficient and scalable synthesis of quantum dots using hexane as the solvent in a non-microfluidic flow reactor system

“…CdSe QD reactions were carried out in a 10 mL stainless steel reactor similar to the apparatus used in previous reports. 40,41 The inlet of a stainless steel (1/16 00 i.d.) tube was connected to an injector valve (Valco) coupled with a 0.5 mL injection loop.…”