3.1.1 SC Toilets
Maric et al. 74, students from University of Connecticut, Storrs, SCT developed and fabrication of a SC toilets for practical application. They conclude that in public bathroom tend to be difficult to keep clean regularly, without checking the functionality of the facility. The problem has been solved by these students to develop a project has an intelligently designed, self-regulating, cleaning system that could be retroactively fitted onto a variety of toilet seats. The durability test indicated that the device would be able to survive the conditions of the working environments commonly associated with bathrooms.
3.1.2 SC Mineral Paints for Architectural Heritage
A mineral silicate paint has been developed by Pal et al. 75 for use of architectural heritage, and to enhance durability. Potassium silicate was the binder agent proposed to give strong adherence and durability to stone and concretes. The SC activity of the mineral paint was assessed by the degradation of organic dyes under solar light irradiation. SC activity compared with the organic binder-based paints and commercial paints, established paints possess high stability as compared the other paints. The SC action on the paint assessed by the photocatalytic degradation of organic dyes under solar irradiation. Figure 18 shows the picture of rhodamine B dye droplet on three kinds of paint surfaces as a function of the solar light exposure along with the photocatalytic degradation kinetics. The silicate paint shows 7 times higher efficiency than the resin and commercial paints in the case of rhodamine B dye and 4–6 times higher efficiency for methylene blue are reported 76.
Fig.18. Photodegradation of rhodamine B silicate paint, (b) resin paint, (c) commercial paint with solar light irradiation time are reproduced from ref.76. Copyright 201.
3.1.3 SC Photovoltaic Devices/Solar Panel
The SCT was mainly originating from a mixture of the photocatalytic oxidative decomposition of organic contaminants and superhydropilicity, which causes water droplets to spread on the TiO2 surface, helping the cleaning process. However, it also observed that most of the photocatalytic effect lost within 5.5 years of outdoor exposure. For dry (waterless) environments, the glass itself should have a nano-structured surface so that dust does not settle on the surface, and water allowed to spread. Therefore, the combination of both SC and antireflective properties with strong durability is desirable for applications in photovoltaic devices 16. The novel and facile fabrication methods have been invented for future practical application besides this the routine completed fabrication processes of coatings (dip coating, spray-coating, and roll to roll coating) were not suited to mass and large-area production 77, 78. The fabrication coatings would be high transmittance, superamphiphobicity, and excellent robustness then only possible generally use in the broad spectrum of applications 79.
The low cost and flexible nanocone films were fabricated by molding polydimethylsiloxane (PDMS) with anodic alumina inverse-nanocone arrays on aluminum substrates. The film was found to be SHP with SC function, it is highly versatile, and enables a new route to fabricate cost-effective AR layers. Figure 19 a) indications of a photograph of a fabricated nanocone film, which demonstrates its outstanding flexibility. 19 b) schematically explains the construction of the solar cell device with nanocone PDMS film attached to the top. 19 c) shows the visual effect of the nanocone AR layer on CdTe devices captured under a “reflection mode”. 19 d) a 2 µL water droplet was placed on the surface of the nanocone PDMS film and the CA was found to be 152°. 19 e) and found to be 98°; this clearly demonstrates the improvement of hydrophobicity with nanocone structure 80.
Fig. 19. a) Flexible nanocone film. b) Schematic structure of the solar cell device, c) Visual effect of the nanocone AR layer on CdTe devices. The bare sample on the right and the sample with PDMS nanocone on top on the left. d) A drop of water on the nanocone PDMS film showing a large contact angle of 152°. e) A drop of water on the flat PDMS film showing a contact angle of 98° are reproduced from 80
Han et al. 81 established a simple and fast process to modify the cover glasses of solar panel/photovoltaic system by atmospheric pressure plasma treatment process. The photovoltaic system was tested for a 20-day outdoor test, the average total conversion efficiency of the bare glass-covered cell was 12.79%.
1.4.3 SC Fabrics/ Textile Industry
Fabrics/Textile goods performance an imperative role in our basic need and also vital role in other fields such as agricultural and health of human being. For this reason, a nonstop development and invention in the area of nanotechnology correlated with textile industry. Today, many researchers have been concentrated on their research attention to the usage of nanotechnology in the fabrics/textile industry has augmented quickly in recent years. Nowadays, nanotechnology had been used to improve textile qualities, such as smoothness, durable, fire retardancy, breathability, yarns and water repellency82, 83. The researcher mainly concentrates on some of the innovative methodologies and to manufacturing high value-added textiles that deliver consumers by the better levels of safety, aesthetics, comfort, and functional performance 84. The researchers design and developed a SC cloth from the uses of nanotechnology and multipurpose chemical finished. Based on lotus leaf concept, researcher established a new concept of SC, and textile surface cleaned as itself without using any laundering action. Gupta and Gulrajani 76 reported that the SCS for textiles and cotton fabrics 48.
Nanocomposite fibers were developed by scientists from IIT Delhi 85, fibers have much superior unique features of SC, dyeability, toughness and thermal stability and electrical conductivity, which depends on the type of nanomaterials used in carbon nanotubes, nano-clays, silica or titanium nanoparticle. They work currently on nanocomposite coatings on textile and nanofibers based on polymer nanocomposites for making functional textiles with improved durability and performance. Simultaneously, Wu et al. 86 reported that dry-wash durability was expected to provide inspiration for use for hash or sensitive conditions.
Yu et al. 87 reported that the TiO2 nanoparticles have been covalently immobilized onto cotton fabrics, first by esterification with MAH, and then co-grafting with HEA under ?-ray irradiation are presented in Fig. 20.
They showed that enhancement laundering durability experiment carried out to measure the effects of the strength of the covalent bonds between the TiO2 nanoparticles and cotton fabrics linked by PHEA graft chains. Further characterization carried out then shows the TiO2 nanoparticles still immobilized on the surface of the cotton fibers after 30 accelerated laundering circles. Finally, concludes that the photocatalyzed SC ability of the functionalized cotton fabrics was well-retained 87. The coating shows excellent durability against organic solvents, acid and base solutions, as well as repeated washing. This SHP coating used for developing functional fabrics for various applications for personal protective clothing. The coating was durable enough to withstand 100 laundry cycles. It also had excellent stability against long immersion times of organic solvents, and acid and base solution 88. A multifunctional superamphiphobic cotton fabric has been invented by coating silica nanoparticles on the cotton fabric surface and further modification by 1H,1H,2H,2H-perfluorooctyl trichlorosilane (FOTS) and the surface free energy of the fabric composite reduced by FOTS modifier presented in Fig.21. They also showed that the prepared cotton fabrics showed high liquid repellency to water, colza oil and n-hexadecane with lower surface tension, show a CA of 158°, 152°, and 153° respectively. The superamphiphobic cotton fabric controlled desirable chemical and mechanical durability, SC, self-healing
3.1.1 SC Toilets