Here, we have reviewed brief ideas of fabrication of superhydrophobic surfaces and their important applications, which were discussed in the concluded national/international workshops and conferences organized by different industries and laboratories of ISRO (Indian Space Research Organization), DRDO (Defence Research and Development Organization) and AERB (Atomic Energy Regulatory Board) in the last four years. A comprehensive overview of wettability, development of fabrication, techniques for artificial superhydrophobic surfaces and their natures and low surface energy materials along with surface texture is presented successfully. The purpose of this review is to assist future development to make robust superhydrophobic surfaces.

The present perspective presents a novel platform for the synthesis of catalyst free photoluminescent carbon nanoparticles derived from the combustion of camphor in a single step flame process. The soot particles were investigated using Fourier transformation infrared spectroscopy, thermogravimetry, Raman, transmission emission microscopy, X-ray diffraction, UV and photoluminescent spectroscopy. The soot particles exhibited a diamond-like carbon nanostructure, with the presence of hydrophobic functional groups imparting superhydrophobic characteristics. The camphor soot particles revealed the presence of highly graphitized amorphous carbon, which was confirmed by the appearance of G, D1 D2, D3 and D4 bands in the Raman spectra. Photoluminescence of the soot particles was observed when soot particles were excited at λ_max. A red shift was clearly noted in the UV spectrum of the soot in different solvents. The agglomeration of camphor soot particles was discussed by measuring the fractal dimensions (D_f) of the particles. Combustion of soot particles occurs at 450 °C, approx. 100 °C lower than that of graphene. In-depth investigations suggest the use of these photoluminescent camphor soot particles for superhydrophobic coating applications.

The attachment of marine organisms, for example, bacteria, proteins, inorganic molecules, and more on a sea-submerged surface is a global concern for marine industries as it controls the surface for further marine growth. Applications requiring the estimation of real-time information from oceanographic sensors conveyed for long-term deployment are vulnerable to biofouling. Therefore, an effective approach to controlling the biofouling that accumulates on marine sensors is paramount. To date, many technologies have been explored to impede biofouling; however, several factors constrain many strategies, including their reliance on environmentally toxic materials, high fabrication costs, poor coatings, and nontransparency. These challenges have motivated work to develop numerous advanced and innovative strategies based on mechanical methods, irradiation, and design of polymeric/nonpolymeric coatings with fouling resistance, fouling release, and fouling degrading coatings to protect marine sensors and housing materials from biofouling. This Review presents recent progress in the developed biofouling control strategies that have been applied to commercially available sensors and sensor housing materials. Moreover, recent findings in the literature are highlighted while considering the wettability principles for air and water environments, antifouling performance, practical feasibility, environmental and economic impact of coatings, and field trial studies. Here, we emphasize how these features can play major roles synergistically to affect antifouling coatings against nano- to microlevel organisms. This review will not only allow researchers to understand the design principles but also contribute to the development of new cost-effective strategies.

A novel self-cleaning polymer composite with self-healing ability to self-repair after chemical and mechanical damage using readily available materials like polydimethylsiloxane (PDMS) and camphor soot particles is developed. With the optimal loading of the camphor soot particles, the composite coating on glass and stainless steel surfaces reveals self-cleaning properties with a water contact angle of 171°. We also demonstrate that any degradation of its surface energy under oxygen plasma etching can be recuperated, demonstrating the self-healing ability of the superhydrophobic surface. The fabricated PDMS/camphor soot hybrid coating exhibited excellent retention of superhydrophobicity against the impact of sand particles from a height of 10–70 cm. In addition, after being damaged chemically by strong acid treatment (1 M HNO₃ solution), the coating can also restore its properties after a short thermal cycle. The quantitative measurement of mechanical properties of self-healing superhydrophobic surfaces is challenging due to their high surface roughness at the micro/nano-scale with a tolerance of low stress. In this work, we have conducted a detailed investigation of the mechanical responses of the camphor soot particle-incorporated PDMS composites by using atomic force microscopy (AFM). Using an AFM tip with a radius of approximately 10 nm, we have quantified different mechanical properties such as stiffness, the plastic work, and the effective adhesive work. Such versatile superhydrophobic surfaces can have wide applications ranging from underwater marine vessels to coating surfaces to protect them from moisture and unwanted penetration of water. These composite coatings are environmentally benign and can be readily coated on various substrates by simple spraying.