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Bioinspiration is an emerging field of study. It translates to the creation of products, devices, and processes by using materials and processes found in living nature. Economic impact of bioinspired materials and surfaces is significant, on the order of several hundred billion dollars per year worldwide. Along the same line, this PhD dissertation attempts on solving two problems using bioinspired solutions: 1) the water crisis and 2) gas bubbles movement.Fresh water sustains human life and is vital for human health. Water scarcity affects more than 40% of the global population and is projected to rise. Furthermore, various factors, including population growth and unsafe industrial practices, have put strain on “clean” water supply in many parts of the world, including the Americas. It is certain than the current supply of fresh water needs to be supplemented to meet future needs. Living nature provides many lessons for water source. It has evolved species, which can survive in the most arid regions of the world by water collection from fog and condensation in the night. Before the collected water evaporates, species have mechanisms to transport water for storage or consumption. In this dissertation, first, an overview of these mechanisms is presented. Then, based on these mechanisms, the work done on bioinspired water harvesters is presented. Based on the results, design and projections of water harvesting towers is also presented. Gas bubbles are of interest in natural and technological applications. These applications include biomedicine, food production, drag reduction, water treatment, oil removal and surface cleaning. On the contrary, gas bubbles may also have a deleterious effect. For example, the gas bubbles produced in oil could potentially cause corrosion of pipelines resulting in reduced equipment life and wasted resources. Therefore, the study of gas bubbles movement in terms of their formation, interaction with underlying surfaces, and their movement is important. It was found that movement of gas bubbles and water droplets are similar in a way. Therefore, in this dissertation, the previously learnt lessons from nature, were also used for the gas bubbles movement. The results from the bioinspired gas bubble movement are also discussed in this dissertation.

Bioinsipration is an emerging field of study. Commercially-available bioinspired products have already affected industries including water treatment, energy conservation and storage, transportation, and data and computing. Bioinspired products are estimated to impact the United States GDP by the order of $400 billion by 2030. The field of bioinspiration is highly interdisciplinary and it involves learning lessons from biological functions, structures, and principles of various objects found in nature. Using the lessons learned, fabricating products and/or surfaces of commercial interest can be produced. In this research, a chapter on lessons learned on painless mosquito bite is presented first. The chapter starts with providing an overview on bioinsipiring attributes of mosquitoes, which are standing on water, sticking to any surface, flying in rain, and painless piercing. The first three attributes are a result of superhydrophobic legs, dry adhesion in the foot, and hydrophobic wings and antifogging eyes, respectively. The understanding of the fourth attribute—painless piercing—is further elucidated by investigating nanomechanical properties of its mouthpart. The mouth is a bundle of seven coherently functioning subparts. Based on experiments and available literature, it was hypothesized that mosquitoes painlessly bite using a combination of pre-bite numbing, the frequency-dependent-gradient in its labrum’s mechanical properties, its serrated-design, and vibratory actuation. At end of the chapter, based on the hypothesis, a set of mosquito-inspired microneedle design guidelines has also been proposed.A second chapter presented is on bioinspired fabrication of water- and oil-repellent leather. Leather is a flexible, yet strong material, which has found applications including footwear, furnishing, automotive, clothing, gloves, sports, and bags. For many applications, the leather should have properties such as liquid-repellency, self-cleaning, low adhesion at high temperature, and anti-smudge. In this study for the first time, artificial leather has been reported to achieve high water- and oil-repellency by using multi-layered nanocomposite coating structure. The coated surface exhibited self-cleaning, low adhesion up to 70°C, and high mechanical durability.