Growth of ZnO nanorods on cotton fabrics via microwave hydrothermal method: effect of size and shape of nanorods on superhydrophobic and UV-blocking properties

Abstract

In this present research, a novel microwave hydrothermal method was applied to cotton fabrics to develop a superhydrophobic surface by rapid synthesis of aligned ZnO nanorods on the surface of the cotton fabric. A two-step approach was used to grow the ZnO nanorods. Firstly, the cotton fabric was coated by a seed layer of ZnO nanocrystals, synthesized using the microwave-assisted sol gel method. Secondly, the ZnO nanorods were grown rapidly on the seeded cotton fabrics using the microwave hydrothermal method. Moreover, a layer of nonfluorinated silane was applied on the as-grown nanorods to fabricate a superhydrophobic surface. Non-fluorinated silane was selected as it is less harmful to the skin than fluorinated silanes. The effect of the zinc nitrate hexahydrate (Zn(NO 3 ) 2 Á6H 2 O) concentration, reaction time and microwave power on the growth of ZnO nanorods was investigated in detail using scanning electron microscopy. The surface topography and roughness of the nanorods grown on the fabrics were studied using atomic force microscopy. EDS analysis and X-ray diffraction techniques were used to study the structural properties of the ZnO nanorods. The ultraviolet protection properties were investigated by a UV-Vis-NIR spectrophotometer. The ZnO nanorods grown on the cotton fabrics exhibited excellent UV blocking properties. A maximum UPF value of 114 was observed for the ZnO nanorods grown on the cotton fabric with 100 mM of zinc nitrate hexahydrate (Zn(NO 3 ) 2 Á6H 2 O). The superhydrophobic properties were examined based on contact angle and roll-off angle measurements, where a maximum water contact angle of 170.2°and a minimum roll-off angle of 1°were found for 25 mM of zinc nitrate hexahydrate. The ZnO-OTMS coated fabrics were evaluated for superhydrophobic durability against mechanical abrasion, laundering, chemical and UV action. Moreover, the ZnO-OTMS coated fabrics showed excellent potential for separation of floating and underwater oil layers or an oil-water mixture.

Functionalization of cotton fabric with ZnO nanoparticles and cellulose nanofibrils for ultraviolet protection

“…There are other studies on UV protection cotton fabrics, the UPF values in which are range from tens to hundreds. [62][63][64] Only from the perspective of UV protection, our research is at a high level.…”

Facile fabrication of superhydrophobic polyester fabric based on rapid oxidation polymerization of dopamine for oil–water separation

“…The idea to prepare superhydrophobic fabrics is to introduce low surface energy substances to reduce the surface tension of the fabric, and to generate nanoparticles on the surface of the fabric or etch them chemically or physically to construct a structure with a micro/ nano rough structure similar to the lotus leaf surface. Therefore, researchers have adopted different strategies, 2 for example, by chemical vapor deposition, 3 sol-gel coating 4,5 and other methods to introduce uorinating agents [8][9][10][11][12][13] and other low surface energy substances into the fabric, or using nanoparticle in situ growth, 14 chemical etching 15 or plasma etching 16,17 to endow the fabric surface with a micro/nano-level rough structure to achieve the superhydrophobic aim. However, the operations of these methods are complicated, or the reagent used is not environmentally friendly, and the prepared superhydrophobic material has poor stability, which seriously hinders practical application.…”

Controllable growth of Cu–Bi co-doped ZnO nanospheres on cotton fabrics and a study on their photocatalytic performance in visible light

“…9,10 ZnO as a wide band gap (3.37 eV) semiconductor material has great chemical stability and biocompatibility, and has high exciton binding energy (60 meV) at room temperature; most research studies chose to attach or grow nanomaterials on the fabric to endow or change the performance of the fabric. [11][12][13][14] For example, Irmak et al 15 reported the growth of ZnO nanowires in carbon bres and proved that ZnO nanowires signicantly improved the photocatalytic performance of carbon bres. Sha et al 16 successfully prepared single-crystalline wurtzite ZnO nanorods on carbon bers and experimental results showed an outstanding degradation of MB solution and good recyclability.…”