Cotton Fabric Substrates Research Articles

The influence of electrode geometry on the electrochemical performance of fabric-based screen-printed coplanar supercapacitors

Coplanar supercapacitors are promising flexible energy storage systems due to the excellent flexibility and tailored shapes and sizes of electrodes. However, the influence mechanism of electrode’ geometry parameter on the electrochemical performance of the flexible coplanar supercapacitors needs to be elucidated to realize the performance enhancement. Herein, the flexible coplanar supercapacitors with different thicknesses, widths and lengths of screen-printed electrodes were constructed on the cotton fabric substrates utilizing multi-walled carbon nanotubes ink and polymer gel electrolytes. The relationship between electrodes' geometry and overall electrochemical performance of flexible coplanar supercapacitors was detailed analyzed and demonstrated by employing equivalent series circuit model and electrode kinetic theory. Furthermore, due to the favorable aspect ratio and relatively low electrode and electrolyte resistance, the fabric-based coplanar supercapacitor with electrode size of 4 × 10 mm shows optimal electrochemical performance with areal capacitance of 3.08 mF cm−2 at 20 mV s−1, fast electrode response and effective kinetic process. Most importantly, the fabric-based supercapacitor exhibits excellent flexibility and cycling performance with capacitance retention rate over 79.6 % after 4000 charge and discharge cycles, indicating application potential in wearable electronic devices. The analysis and assessments of electrodes' geometry provides theoretical reference for the electrode design and optimization of flexible coplanar supercapacitors.

A monopole antenna with cotton fabric material for wearable applications

A monopole antenna operated at 2.45 GHz and embedded with artificial magnetic conductor (AMC) for wearable communication systems is investigated in this article. The proposed antenna is composed of a metalized loop radiator with a coplanar waveguide microstrip feedline which is affixed on a cotton fabric material substrate. As well, a cotton-based AMC surface is utilized to eliminate the body’s absorbed radiation and enhance the gain of the antenna. It is composed of 5 × 5 array unit cells etched with I-shaped slots. Using this configuration, simulations show that the specific absorption rate (SAR) level was significantly reduced. Considering flat and rounded body parts, it was found that the SAR values averaged over 10 g at a distance of 1 mm away from the tissues model were only 0.18 W/kg and 0.371 W/kg, respectively. Additionally, the antenna gain was improved up to 7.2 dBi with an average radiation efficiency of 72%. Detailed analysis with experimental measurements of the cotton-based antenna for different operation scenarios is introduced. The measured data show a good correlation with the electromagnetic simulation results.

Preparation of AgBr decorated ZnO/ZnS nanocomposite for photocatalytic and antibacterial applications

The first synthesis of AgBr decorated ZnO/ZnS heterostructure for powerful photocatalytic and antibacterial purposes is reported. The analytical results showed that the introduction of AgBr into the ZnO/ZnS matrix resulted in an increase in the specific surface area and a decrease in the optical energy gap of the sample. Moreover, various reactive species such as •O2−, •OH, Ag°, Br°, photogenerated holes and electrons were formed on the surface of the ZnO/ZnS/AgBr nanocomposites upon exposure to light. These factors played a crucial role in enhancing electron-hole pair separation and improving the photocatalytic efficiency and antibacterial activity of the material. The nanocomposites were investigated for photocatalytic degradation of synthetic dye solution under UVA-visible light irradiation. The results showed that the superior first-order kinetic rate constants (kapp) for the degradation of methylene blue and methyl orange of the as-prepared ternary composite under UVA irradiation were significantly improved to 0.109 and 0.030 min−1, respectively; which was more than twice the values of the sample without AgBr addition. Moreover, the results of inhibition of Gram-positive and Gram-negative bacteria on cotton fabric substrate showed that both the ZnO/ZnS and ZnO/ZnS/AgBr nanocomposites exhibited excellent antimicrobial efficacy of more than 99.95% under natural light.

Versatile superhydrophobic bismuth molybdate cotton fabric for oil/water separation and decompose dyestuff.

Water pollution caused by the discharged insolubility petroleum contaminants and organic compound dyes seriously threatens the natural self-purity capacity of the water body and the survival of aquatic species, so it is imperative to restraint the deterioration of the aquatic environment. In this paper, pathways are propounded for the simultaneous removal of insoluble spilling oil and organic dye contaminants. Particularly, hydrophobic ZnSnO3 after stearic acid modification and Bi2MoO6 photocatalysts are introduced into the cotton fabric substrate through solution dip-coating. The durability of the prepared fabric suffers from the acid-base corrosion, thermal treatment and mechanical wear, while still exhibiting remarkable water-repellent (WCA > 150°) property. Furthermore, the remarkable photocatalytic activity makes it possible for reusable degradation and the primary active species, namely the holes, to be verified by the radicals-capturing experiment. It is worth observing that as-prepared superhydrophobic fabric possesses admirable water-proof property and cycling durability of decomposing toxic water-soluble organic dye, thereby contributing to further realizing the ecological concept of clear waters.

Ionic interaction-driven switchable bactericidal surfaces

Bacteria in the external environment inevitably invade the wound and subsequently colonize the wound surface during surgery and biomedical operations, which slows down the process of wound healing and tissue repair; this poses a significant threat to human health. Therefore, the development of an intelligent antibacterial surface has become the focus of research in the field of antimicrobial strategies, which has important social and economic significance. Here, we present a simple approach of producing an ionic interaction-driven anionic activation substratum which is then functionalized with cationic molecules through coulombic interactional immobilization. The switchable multifunctional antibacterial surface can decrease bacterial attachment and inactivate the attached microorganisms, thus overcoming the conventional challenge for antibacterial surfaces. Briefly, poly (3-sulfopropyl methacrylate potassium salt) (PSPMA) brushes were constructed by surface-initiated atom transfer radical polymerization on silicon or cotton fabric substrates, and a positive-charged component, namely lysozyme (LYZ), hexadecyl trimethyl ammonium bromide (CTAB) or chitosan (CS), was loaded on negative-charged sulfonate groups through electrostatic interactions. The resultant brush-grafted surfaces exhibited more than ∼95.5% bactericidal efficacy and ∼92.8% release rate after the introduction of an adequate amount of contra-ions (1.0 M; Na+ & Cl−) against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, thus achieving a regenerated surface through the cyclic process of “assembly-dissociation”. Smart cotton fabric (Fabric-PSPMA/LYZ and Fabric-PSPMA/CS) surfaces were constructed, which were found to promote wound epidermal tissue regeneration with a higher efficiency after 7-day in vivo studies. This ionic interaction-driven method used in the present work is simple and can reversibly renew antibacterial surfaces, which will help in the wider utilization of switchable antibacterial materials with a more ecologic and economic significance. Statement of significanceSmart antibacterial surfaces with renewable characteristics have attracted considerable interests over the past few years. Here, we used ionic interaction-driven force to manipulate dynamic conformational changes in PSPMA surface brushes, accompanied by highly switchable bacteria killing and bacteria releasing behaviors. Different cationic molecules were also designed for assembly/dissociation on the PSPMA-modified surfaces, and the essential parameters, including chemical structures, molecular weight, and cationic charge density, were investigated. With the refined structural combinations and the balance of bacteria killing/bacteria releasing behaviors, smart cotton fabrics (e.g., Fabric-PSPMA/lysozyme and Fabric-PSPMA/chitosan) were designed that could promote wound healing and tissue repair. These results contribute to the fundamental understanding of a switchable cationic-anionic pair design and the corresponding practical, renewable, highly antibacterial fabric.

Admicellar Polymerization of Tris(2-acryloyloxyethyl)phosphate on Cotton Fabric for Flame Retardant Finishing

To improve the flame retardant property, the admicellar polymerization process was applied to polymerize and coat the tris(2-acryl-oyloxyethyl)phosphate (PTAP) monomer on cotton fabric (CF). The polymerization was completed with the support of a cationic surfactant cetyltrimethylammonium bromide (CTAB) and an initiator 2,2′-azobisisobutyronitrile (AIBN). Thermogravimetric analysis (TGA) and limiting oxygen index test (LOI) were performed to find out the effects on degradation and flammability of modified cotton fabric. One of the modified cotton fabric samples (CF-PTAP) show the decrease in onset temperature caused by acid catalyzed dehydration released from PTAP polymer placed on cotton fabric substrate. The increase in char yield (20.9%) and LOI value (25.0% demonstrated a condensed phase flame retardant action) owing to the presence of PTAP polymer on substrate.

Textile electrodes for bioimpedance measuring

This article deals with the development and comparison of eight different electrodes made out of a cotton fabric substrate, a silver coated yarn and partly conductive finishes, i.e. a PEDOT:PSS Orgacon ICP 1050 dip-coating and a Powersil coating. The purpose is the application especially in the medical field of angiopathy like for bioimpedance measurements during compression therapies. To be able to compare the suitability of the electrodes, various tests have been performed of the coating abrasion resistance, the stability of electrical resistance values, as well as resistance and bioimpedance measurements. Significant differences between the electrodes regarding their resilience and resistance that are visualized in a value-added analysis were found, with one hand-embroidered, one machine-sewn and one commercial electrode showing optimum properties.

Fabrication and characterization of a thin coated adsorbent for antibiotic and analgesic adsorption: Experimental investigation and statistical physical modelling

Sulfamethoxazole (antibiotic) and acetaminophen (analgesic) are classed as common Contaminants of Emerging Concern (CEC) that have been detected in significant quantities in sewage treatment plants in Malaysia and other countries. Unfortunately, the conventional sewage treatment plants are not effective to reduce the concentrations of these compounds. Therefore, this study introduces a novel Contaminant Emerging Remover (COATER) to face the pollution caused by these CECs. This COATER was formulated using epoxidized neutral rubber (ENR-50) and poly(vinyl) chloride (PVC) as binders besides activated carbon as an adsorbent, which was coated on white cotton fabric (substrate) via brushing technique. Characterization analysis of this COATER was performed using SEM-EDX, FTIR and BET quantifications to study the surface chemistry and to obtain insights about the adsorption mechanism. Results of surface morphology analysis showed a good distribution of activated carbon onto the substrate where the surface area and pore volume of the COATER were 64.3 m2/g and 0.07 cm3/g, respectively. Adsorption isotherms of tested CECs on COATER were experimentally quantified at different temperatures. A monolayer adsorption model based on statistical physics was used to understand the adsorption mechanism. Modelling results showed that the adsorption orientation of tested molecules was similar but it could occur a change in the interaction of these pollutants with the adsorption sites of COATER surface during the removal process since this adsorbent contained a variety of functional groups. It was concluded that the adsorption mechanism of tested adsorbates on COATER included pore interaction, chemical bonding and electrostatic forces.

Grain boundaries of Co(OH)2-Ni-Cu nanosheets on the cotton fabric substrate for stable and efficient electro-oxidation of hydrazine

Metal/metal hydroxide hybrid heterostructures exhibits superior performances in diverse research fields, especially in catalysis due to the presence of ample grain boundary interfaces and the strong metal/metal hydroxide synergistic actions. Herein, Co(OH)2-Ni hybrid heterostructures with a crystalline Ni and Co(OH)2 is prepared on the cotton fabric substrate by a simple electrochemical process. The Co(OH)2-Ni hybrid heterostructures are explored as a highly active catalyst for the electro-oxidation of hydrazine in an alkaline medium. The existence of ample grain boundary interfaces and promotional synergistic effect between the nanocrystalline metallic Ni and Co hybrid heterostructures lead to a very low-onset hydrazine oxidation potential of −0.06 V vs RHE. Moreover, the Co(OH)2-Ni hybrid heterostructured electrode exhibits excellent long-term catalytic stability.

Electrochemical Analysis of the Printed NiCo2O4 // Reduced Graphene Oxide Solid-State Hybrid Supercapacitors on Fabric Substrates for Wearable Applications

The rapid developments of the wearable or body-integrated electronics and boom in the portable healthcare devices have increased the demand of the wearable energy storage devices [1-3]. Inkjet printing is an emerging technology to transfer the device components on the variety of the substrates at the specific locations. However, achieving the good electrochemical performance of the printed electrode materials on wearable substrates is still a major challenge [4, 5]. Here we report a printed, binder-free, flexible, and high-performance NiCo2O4// Reduced Graphene Oxide (rGO) battery- supercapacitor hybrid device on cotton fabric substrates. A thin layer of polydimethysiloxane (PDMS) polymer was applied over the textile fabric for surface planarization. The NiCo2O4 micro-flower arrays were successfully fabricated over this cloth substrates using printing and low-temperature heat treatment method and further treated with the UV irradiation. The crystalline and conducting NiCo2O4 micro-flower array layer acts as a self-supporting electrode, and its open space structure ensures the fast electron transport and full utilization of the electrode surface. The printed NiCo2O4 // rGO asymmetric device with the LiCl –PVA gel electrolyte displays good electrochemical performance within a potential window of 0 to 1.6 V. The fabricated device exhibited excellent electrochemical performance including high areal capacitance of 7.2 F/cm2 (2650 F/g) at a current density of 1 mA/cm2, good cycle life (89 % capacitance retention after 5000 charge-discharge cycles), high rate capability, high power density, high energy density, and low charge transfer resistance both in the normal and flexed conditions. The obtained results are comparable to the existing literature for the high temperature processed NiCo2O4 based energy storage devices, and therefore the reported method has a great potential for the direct fabrication of electrode materials over the temperature sensitive fabric substrates. These fabric based supercapacitors can be easily integrated with the various flexible and wearable devices and exhibit the great beneficial for the next generation of the wearable electronic devices. References Zeng, W., et al., Fiber‐based wearable electronics: a review of materials, fabrication, devices, and applications. Advanced Materials, 2014. 26(31): p. 5310-5336.Kim, J., et al., Advanced materials for printed wearable electrochemical devices: A review. Advanced Electronic Materials, 2017. 3(1): p. 1600260.Bandodkar, A.J., Wearable biofuel cells: Past, present and future. Journal of The Electrochemical Society, 2017. 164(3): p. H3007-H3014.Sundriyal, P. and S. Bhattacharya, Inkjet-Printed Electrodes on A4 Paper Substrates for Low-Cost, Disposable, and Flexible Asymmetric Supercapacitors. ACS applied materials & interfaces, 2017. 9(44): p. 38507-38521.Choi, K.-H., D.B. Ahn, and S.-Y. Lee, Current status and challenges in printed batteries: toward form factor-free, monolithic integrated power sources. ACS Energy Letters, 2017. 3(1): p. 220-236.

Facile and eco‐friendly fabrication of hierarchical superhydrophobic coating from eggshell biowaste

AbstractThis study reports a facile and sustainable approach to fabricate superhydrophobic coating from eggshell biowaste. The coating was prepared by ball milling chicken eggshells, composed of hydrophilic calcium carbonate (CaCO3), to microsized particles followed by surface hydrophobilizing with stearic acid (C17H35COOH) to form low surface energy nanosized calcium stearate ((C17H35COO)2Ca) through the esterification of hydroxyl groups (‐OH) absorbed on a surface of CaCO3 with carboxyl groups (–COOH) of stearic acid. Then, a layer of modified eggshell particles dispersed in polystyrene (PS) binder was dip‐coated on a substrate. A coated surface with water contact angles of 151° ± 1° on glass and 153° ± 1° on cotton fabric substrates was achieved when a 4:1 weight ratio of the modified eggshell:PS was used. The uniform distribution of the modified eggshell particles throughout the coating led to a surface with high degree of hierarchical micro‐nanoscale roughness which resulted in superhydrophobicity. The superhydrophobic eggshell coating showed good environmental stability, self‐cleaning, and oil/water separation properties. These results suggest that eggshell biowaste can be utilized for superhydrophobic applications.

Silver Nanowire Ink for Flexible Circuit on Textiles.

Low cost electronics implemented in textiles could pave the way to a fully new generation of smart products in the fields of healthcare, sport, fashion, and safety. Although many methods have found their way into the market, many problems still need to be solved and much progress has to be made to enable the commercial exploitation of such products. In this paper, silver nanowires of 60–100 nm in diameter and 8–15 μm in length were achieved by the polyol solvothermal method, and aqueous silver nanowire conductive inks were prepared with the synthesized silver nanowires as the conductive phase, in the presence of polyaniline, guar, and hydrochloric acid. The conductive inks were printed on cotton fabric substrate by screen printing process. The effects of the amount of silver nanowires, layers of coating, and treatment temperature on the microstructure and electrical properties of samples were investigated by scanning electron microscopy and the four-point probe method. The results show that the conductivity and densification of the samples increased with increased amount of silver nanowires, layers of coating, and treatment temperature. The heat treatment helped to improve densification of the silver nanowires and conductivity of the sample. The resistance of the samples increased after bending due to loosening of the overlap between the silver nanowires.

Substrate Dependent Analysis of Printed Sensors for Detection of Volatile Organic Compounds

This paper investigates all-printed gas sensors developed on different unconventional substrates and their effect of the detection of various volatile organic compounds (VOCs). An inkjet printing system is used to deposit the functional materials on PET (polyethylene terephthalate), paper and cotton fabric substrates. The different surface morphology and texture of the substrates are explored and used for developing the VOC sensors. Silver (Ag) nanoparticles based ink is used for printing the interdigital electrodes and the interconnect lines, whereas carbon black paste is used as the sensing layer. Sensors are tested against two different concentrations i.e. 4 and 22 ppm (parts per million) of three types of VOCs, i.e. acetone, ethanol and isopropanol. The comparative studies show a strong dependence of the VOCs detection on the type of substrates. Pros and cons of all the substrates, based on the processability, wearability, sensitivity and response times etc. are evaluated. This research presents significant contribution towards developing large area, low-cost and wearable VOC sensors, which are highly demanding in industrial and environmental monitoring as well as for potential analytes in biosensors to detect various chronic diseases.

Classical Least Squares-Assisted Mid-Infrared (MIR) Laser Spectroscopy Detection of High Explosives on Fabrics.

Mid-infrared (MIR) laser spectroscopy was used to detect the presence of residues of high explosives (HEs) on fabrics. The discrimination of the vibrational signals of HEs from a highly MIR-absorbing substrate was achieved by a simple and fast spectral evaluation without preparation of standards using the classical least squares (CLS) algorithm. Classical least squares focuses on minimizing the differences between the spectral features of the actual spectra acquired using MIR spectroscopy and the spectral features of calculated spectra modeled from linear combinations of the spectra of neat components: HEs, fabrics, and bias. Samples in several combinations of cotton fabrics/HEs were used to validate the methodology. Several experiments were performed focusing on binary, ternary, and quaternary mixtures of TNT, RDX, PETN, and fabrics. The parameters obtained from linear combinations of the calculated spectra were used to perform discrimination analyses and to determine the sensitivity and selectivity of HEs with respect to the substrates and to each other. However, discrimination analysis was not necessary to achieve successful detection of HEs on cotton fabric substrates. The RDX signals ( mRDX > 0.02 mg) on cotton were used to calculate the limit of detection (LOD). The signal-to-noise ratios (S/N) calculated from the spectra of cotton dosed with decreasing masses of RDX until S/N ≈ 3 resulted in a LOD of 15-33 µg, depending on the vibrational band used. Linear fits generated by comparing the mass dosed RDX with the fraction predicted were also used to calculate the LOD based on the uncertainty of the blank and the slope. This procedure resulted in a LOD of 58 µg. Probably the most representative value of the method LOD was calculated using an interpolation of a threshold determined using the predicted average value for the blank plus 3.28 times the standard deviations ( p-value threshold) for low surface dosages of RDX (LOD = 40 µg). The contribution demonstrates that to achieve HE detection on fabrics using the proposed algorithm, i.e., determining the presence/absence of HEs on the substrates, the library must contain the spectra of HEs, substrates, and potential interferents or that these spectra be added to the models in the field. If the model does not contain the spectra of the fabric components, there is a high probability of finding false positives for clean samples (no HEs) and a low probability for failed detection in samples with HEs. More work will be required to demonstrate that these new approaches to HE detection work on real-world samples and when contaminating materials are present in the samples.

Flame retardant and hydrophobic coatings on cotton fabrics via sol-gel and self-assembly techniques

Nanocoatings consisting of ammonium polyphosphate (APP), sodium montmorillonite (MMT), and vinyltrimethoxysilane (VTMS) were prepared via self-assembly and in situ sol-gel techniques and applied onto cotton fabrics to achieve both flame retardancy and hydrophobicity. The impacts of APP concentration on the hydrophobicity and fire resistance of the coated fabrics were investigated. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) characterization results verified the hydrolysis-condensation reaction of VTMS and the formation of Si-O-Si network structure. X-ray diffraction (XRD) proved the formation of a layered structure based on MMT nanosheets in the coatings. Both vertical flame test (VFT), limiting oxygen index (LOI), thermogravimetric analysis (TGA) and microscale combustion calorimeter (MCC) characterization were conducted to evaluate the flame retardancy, thermostability and heat release behavior of the coated cotton fabrics, respectively. The results suggested that a higher concentration of APP is beneficial for both hydrophobicity and flame retardancy of the coated substrates. Overall, our research provides a facile and very effective approach to prepare flame retardant and hydrophobic multifunctional coating for cotton fabric and other substrates.

Superhydrophobic organosilicon-based coating system by a novel ultravoilet-curable method

A robust superhydrophobic organosilica sol-gel-based coating on a cotton fabric substrate was successfully fabricated via a cost-effective one-step method. The coating was prepared by modification of silica nanoparticles with siloxane having long alkyl chain that allow to reduce surface energy. The coating on cotton fabric exhibited water contact angle of 151.6°. The surface morphology was evaluated by scanning electron microscopy, and surface chemical composition was measured with X-ray photoelectron spectroscopy. Results showed the enhanced superhydrophobicity that was attributed to the synergistic effect of roughness created by the random distribution of silica nanoparticles and the low surface energy imparted of long-chain alkane siloxane. In addition, the coating also showed excellent durability against washing treatments. Even after washed for 30 times, the specimen still had a water contact angle of 130°, indicating an obvious water-repellent property. With this outstanding property, the robust superhydrophobic coating exhibited a prospective application in textiles and plastics.

Toward Graphene-Based Passive UHF RFID Textile Tags: A Reliability Study

This paper discusses the fabrication, wireless performance, and reliability of graphene-based passive ultrahigh-frequency radio-frequency identification (RFID) tags on a fabric substrate. The conductive ink comprising functionalized graphene nanoplatelets is deposited directly on a cotton fabric substrate to fabricate the tag antennas. After attaching the chips, the tag performance is evaluated through wireless tag measurements before and after high-humidity conditions, bending, and stretching. Initially, the peak read range of the tag is about 1.6 m, which increases to 3.2 m in 100% humidity conditions. Additionally, after drying, the performance of the tag returns back to normal. In a bending test, the read range of a bent tag decreases below 1 m. Furthermore, the read range of the tag in a nonbended state gradually decreases and is about 1.1 m after 100 bending cycles. According to our measurements, stretching has a serious detrimental effect on these tags and they cannot be considered stretchable. However, these initial results show that this low-cost and eco-friendly graphene RFID tag has a remarkable and unique response to moisture and high reliability in harsh bending conditions. Overall, it also has a strong potential to be used in future wearable sensor applications.

Robust Nanostructured Silver and Copper Fabrics with Localized Surface Plasmon Resonance Property for Effective Visible Light Induced Reductive Catalysis

Inspired by high porosity, absorbency, wettability, and hierarchical ordering on the micrometer and nanometer scale of cotton fabrics, a facile strategy is developed to coat visible light active metal nanostructures of copper and silver on cotton fabric substrates. The fabrication of nanostructured Ag and Cu onto interwoven threads of a cotton fabric by electroless deposition creates metal nanostructures that show a localized surface plasmon resonance (LSPR) effect. The micro/nanoscale hierarchical ordering of the cotton fabrics allows access to catalytically active sites to participate in heterogeneous catalysis with high efficiency. The ability of metals to absorb visible light through LSPR further enhances the catalytic reaction rates under photoexcitation conditions. Understanding the modes of electron transfer during visible light illumination in Ag@Cotton and Cu@Cotton through electrochemical measurements provides mechanistic evidence on the influence of light in promoting electron transfer during heterogeneous catalysis for the first time. The outcomes presented in this work will be helpful in designing new multifunctional fabrics with the ability to absorb visible light and thereby enhance light‐activated catalytic processes.

Study of plasma-induced graft polymerization of stearyl methacrylate on cotton fabric substrates

A simple and facile method to prepare the cotton fabric with hydrophobicity was described in the present work. In the one-step process, the cotton fabric pre-impregnated with the monomer solution of stearyl methacrylate (SMA) was placed in the plasma chamber and followed by glow discharge of the Helium low temperature plasma. The cotton fabrics before and after the plasma treatment were characterized by field emission scanning electron microscopy (FESEM), infrared spectroscopic analysis (FTIR), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA), respectively. The wettability of the cotton fabrics was evaluated by contact angle measurement. Fabric Hand Values and mechanical properties were also measured in the experiment.The results showed that polymer films could be coated on the cotton fibers through the plasma induced grafting polymerization of SMA. The modified cotton fabrics exhibited an extraordinary hydrophobicity with a contact angle of 149° for a 5μL water droplet and excellent thermal stability. The relative hand value and mechanical breaking strength of the cotton fabrics declined slightly after graft polymerization of SMA by the plasma.

Robust Flower‐Like TiO2@Cotton Fabrics with Special Wettability for Effective Self‐Cleaning and Versatile Oil/Water Separation

Inspired by the hierarchical structure of the mastoid on the micrometer and nanometer scale and the waxy crystals of the mastoid on natural lotus surfaces, a facile one‐step hydrothermal strategy is developed to coat flower‐like hierarchical TiO2 micro/nanoparticles onto cotton fabric substrates (TiO2@Cotton). Furthermore, robust superhydrophobic TiO2@Cotton surfaces are constructed by the combination of hierarchical structure creation and low surface energy material modification, which allows versatility for self‐cleaning, laundering durability, and oil/water separation. Compared with hydrophobic cotton fabric, the TiO2@Cotton exhibits a superior antiwetting and self‐cleaning property with a contact angle (CA) lager than 160° and a sliding angle lower than 5°. The superhydrophobic TiO2@Cotton shows excellent laundering durability against mechanical abrasion without an apparent reduction of the water contact angle. Moreover, the micro/nanoscale hierarchical structured cotton fabrics with special wettability are demonstrated to selectively collect oil from oil/water mixtures efficiently under various conditions (e.g., floating oil layer or underwater oil droplet or even oil/water mixtures). In addition, it is expected that this facile strategy can be widely used to construct multifunctional fabrics with excellent self‐cleaning, laundering durability, and oil/water separation. The work would also be helpful to design and develop new underwater superoleophobic/superoleophilic materials and microfluidic management devices.