The development of surfaces which reduce biofouling has attracted much interest in practical applications. Three picosecond laser generated surface topographies (Ti1, Ti2, Ti3) on titanium were produced, treated with fluoroalkylsilane (FAS), then characterised using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Raman Spectroscopy, Fourier Transform Infra-Red (FTIR) spectroscopy, contact angle measurements and white light interference microscopy. The surfaces had a range of different macro/micro/nano topographies. Ti2 had a unique, surface topography with large blunt conical peaks and was predominantly a rutile surface with closely packed, self-assembled FAS; this was the most hydrophobic sample (water contact angle 160°; ΔG was -135.29mJm). Bacterial attachment, adhesion and retention to the surfaces demonstrated that all the laser generated surfaces retained less bacteria than the control surface. This also occurred following the adhesion and retention assays when the bacteria were either not rinsed from the surfaces or were retained in static conditions for one hour. This work demonstrated that picosecond laser generated surfaces may be used to produce antiadhesive surfaces that significantly reduced surface fouling. It was determined that a tri-modally dimensioned surface roughness, with a blunt conical macro-topography, combined with a close-packed fluoroalkyl monolayer was required for an optimised superhydrophobic surface. These surfaces were effective even following surface immersion and static conditions for one hour, and thus may have applications in a number of food or medical industries.

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Stable superhydrophobic and superhydrophilic surfaces were created using laser surface micro/nano patterning. These were based on periodic 3D micro/nanostructures produced on 316L stainless steel over large areas using nanosecond and picosecond laser surface fabrication. The effects of laser processing parameters on controlling the micro-/nano-topographical characteristics of 24 different types of structures were presented. Surface roughness, surface chemical composition and wettability (via water contact angle) of these surfaces were characterised. Aging experiments were carried out for up to 8 months to analyse the durability of the prepared surfaces under three conditions of water (hot, normal and icy). Samples with superhydrophobic characteristics, processed with the ps or ns lasers in air, kept dry (water repellent) for over 8 months when tested in ice water (0C-4C), whilst those stored in hot water (80C) or room temperature water could only be kept dry for 3-14 weeks. Samples processed in water had shorter water repellent life and samples processed with the ns laser in air had the longest water repellent periods. The hybrid superhydrophobic and superhydrophobic surfaces had a stability life for water repellent and water spreading of over 6 months.