Silica nanowires: Growth, integration, and sensing applications

Abstract

This review (with 129 refs.) gives an overview on how the integration of silica nanowires (NWs) into micro-scale devices has resulted, in recent years, in simple yet robust nano-instrumentation with improved performance in targeted application areas such as sensing. This has been achieved by the use of appropriate techniques such as di-electrophoresis and direct vapor-liquid-growth phenomena, to restrict the growth of NWs to site-specific locations. This also has eliminated the need for post-growth processing and enables nanostructures to be placed on pre-patterned substrates. Various kinds of NWs have been investigated to determine how their physical and chemical properties can be tuned for integration into sensing structures. NWs integrated onto interdigitated micro-electrodes have been applied to the determination of gases and biomarkers. The technique of directly growing NWs eliminates the need for their physical transfer and thus preserves their structure and performance, and further reduces the costs of fabrication. The biocompatibility of NWs also has been studied with respect to possible biological applications. This review addresses the challenges in growth and integration of NWs to understand related mechanism on biological contact or gas exposure and sensing performance for personalized health and environmental monitoring.

Influence of substrate temperature on the morphology of silicon oxide nanowires synthesized using a tin catalyst

“…. SiO x ( x ≤ 2) nanowires have diverse and flexible morphology, good biocompatibility, a low refractive index, and intense photoluminescence at room temperature, and are compatible with conventional semiconductor technology . The surface of these nanostructures can be easily modified and functionalized.…”

“…Usually, silicon oxide nanowires are synthesized by the vapor‐liquid‐solid mechanism on catalyst particles using the thermal evaporation method . However, this method is characterized by high temperatures, which is not always suitable for device applications.…”

“…Functionalized silicon oxide nanowires are used to control surface wettability [10], which is important for biological applications and for the enhancement of boiling heat transfer on nanostructured surfaces [10,11]. Usually, silicon oxide nanowires are synthesized by the vapor-liquid-solid mechanism on catalyst particles using the thermal evaporation method [2,4,5]. However, this method is characterized by high temperatures, which is not always suitable for device applications.…”

Nanowire Chemical/Biological Sensors: Status and a Roadmap for the Future

“…Silica NWs (SiO 2 NWs), however,have been substantially documented as an excellent material for sensing applications because of their ease of modification, functionalization, and biocompatibility. [48] Si/Ge NWs can be synthesized through methods such as thermal evaporation. [49,50] Ac ommon technique for growing various inorganic NWs is the vapor-liquid-solid (VLS) method by using chemical vapor deposition (CVD) processes.…”

Ni‐Catalyzed Growth of Silica Nanowires From Amorphous Silicon Films and Growth Mechanism

“…Silica nanowires (NWs) have received a considerable amount of attention for applications such as low-dimensional waveguides, scanning near-field optical microscopy, blue light emitters, nanoscale optical devices, and sensors. [1][2][3] They have particularly high potential for environmental and biological sensor applications owing to their large surface-to-volume ratio and excellent physical and chemical stability. [4,5] To meet diverse application requirements, a variety of methods for producing silica NWs have been proposed.…”