Integration of ZnO/ZnS nanostructured materials into a cotton fabric platform

Abstract

Inorganic semiconductor nanostructures coupled to flexible substrates such as natural and synthetic fibrous materials have been studied for a wide range of potential applications that include wearable electronics, protective textiles, portable and flexible photovoltaic and solar cell devices. Here, we report the fabrication of ZnO/ZnS core-shell nanorod arrays on a cotton platform via a simple, low-temperature hydrothermal growth technique. ZnO nanorods were converted to ZnO/ZnS core-shell nanorod arrays through a mild sulfidation process with sodium sulfide. TEM, XRD, and XPS were used to characterize the nanorods to reveal a highly crystalline ZnO core with a polycrystalline ZnS shell. Photoluminescence measurements demonstrate a remarkably large UV emission for the ZnO/ZnS nanorod arrays on cotton. Such materials are anticipated to be useful for wearable, portable electronic devices and as protective textiles.

Wearable Carbon Monoxide Sensors Based on Hybrid Graphene/ZnO Nanocomposites

“…Among them, cotton fabrics are currently highly researched, not only because of their excellent properties (i.e., high flexibility, low cost, high moisture absorbency, good mechanical strength, good biocompatibility, and biodegradability), but also due to the fact that these substrates can be integrated as smart clothing to support the advancement of industrial revolution 4.0 [26], [27]. Currently, surface-modified cotton fabrics have been applied for several wearable devices, including UV filter [28]- [30], superhydrophobic functional garment [31], flame resistance composite [32], anti-bacterial component [33], and gas sensors [34]- [37].…”

ZnO Microstructures as Flame-Retardant Coatings on Cotton Fabrics

“…A slight reduction in the average sizes of the ZnO/ZnS core/shell rods occurred during the sulfidation process ( l = 1207 ± 323 nm, w = 234 ± 42 nm) (Figure 2a,c). 39 Figure 2e shows that single crystals of ZnO coated the entire cellulose fiber. The average thickness of the polycrystalline ZnS shell was 42.4 ± 7.5 nm, as measured from TEM images (Figure 2f).…”

“…Figure 2a–d shows the representative SEM images of cotton fibers coated with ZnO and ZnO/ZnS core/shell rods generated by a 24 h reaction, which were fabricated using a hydrothermal process previously reported by Athauda et al (see the Procedures section). 39 ZnO rods were produced with an average length of 1300 ± 285 nm and a width of 137 ± 39 nm (Figure 2a,c). A slight reduction in the average sizes of the ZnO/ZnS core/shell rods occurred during the sulfidation process ( l = 1207 ± 323 nm, w = 234 ± 42 nm) (Figure 2a,c).…”

“…36−38 ZnO and ZnO/ZnS rods were grown on cotton fabrics using a hydrothermal method previously published by our group. 39,40 In this paper, we show that even loosely adsorbed spherical microparticles of ZnO and ZnS can reduce the heat release rate (HRR) when coated on cotton fabrics independent of an organic flame retardant. We also show that the uniform protective coating of ZnO and ZnO/ZnS rods on the cotton surface results in a lower peak HRR (PkHRR), a lower fire growth rate (FIGRA) index, a lower maximum average rate of heat emission (MARHE), and a lower specific extinction area (SEA) compared to cotton alone.…”

“…To the best of our knowledge, no studies have investigated the flame-retardant properties of these ZnO-based coatings on cotton surfaces alone without the aid of other, usually harmful, flame-retardant additives. The designed Zn-based microparticle coatings were expected to act as a protective layer of insulation , and as a smoke suppressant because zinc salts have been shown to reduce the production of smoke during burning. − ZnO and ZnO/ZnS rods were grown on cotton fabrics using a hydrothermal method previously published by our group. , In this paper, we show that even loosely adsorbed spherical microparticles of ZnO and ZnS can reduce the heat release rate (HRR) when coated on cotton fabrics independent of an organic flame retardant. We also show that the uniform protective coating of ZnO and ZnO/ZnS rods on the cotton surface results in a lower peak HRR (PkHRR), a lower fire growth rate (FIGRA) index, a lower maximum average rate of heat emission (MARHE), and a lower specific extinction area (SEA) compared to cotton alone. , …”