This paper analyses the effect of a solar chimney used to enhance the convective currents within a solar still. Moreover, a condenser was also installed to improve the condensation process. Condensers in solar stills typically consist of fresh seawater flowing through a bank of tubes. However, in the configuration presented, water vapour was passed through a number of ducts immersed in seawater. This solar still was constructed and tested under natural weather conditions using a typical simple solar still as a benchmark. When comparing the efficiency based on the actual evaporator (basin) area, one notes that the solar still with the solar chimney and condensers performed 8.8% better. The simple still produced 4.7 L/m² d, while the modified still generated 5.1 L/m² d with the majority of the yield (59%) condensing in the condensers of the still. This clearly shows that enhanced convection and condensation increases the evaporation efficiency and hence the distillation process of a solar still.

Photocatalysis has long been touted as one of the most promising technologies for environmental remediation. The ability of photocatalysts to degrade a host of different pollutants, especially recalcitrant molecules, is certainly appealing. Titanium dioxide (TiO₂) has been used extensively for this purpose. Anodic oxidation allows for the synthesis of a highly ordered nanotubular structure with a high degree of tunability. In this study, a series of TiO₂ arrays were synthesised using different electrolytes and different potentials. Mixed anatase-rutile photocatalysts with excellent wettability were achieved with all the experimental iterations. Under UVA light, all the materials showed significant photoactivity towards different organic pollutants. The nanotubes synthesised in the ethylene glycol-based electrolyte exhibited the best performance, with near complete degradation of all the pollutants. The antibacterial activity of this same material was similarly high, with extremely low bacterial survival rates. Increasing the voltage resulted in wider and longer nanotubes, characteristics which increase the level of photocatalytic activity. The ease of synthesis coupled with the excellent activity makes this a viable material that can be used in flat-plate reactors and that is suitable for photocatalytic water treatment.