Heterogeneous photocatalysis using titanium dioxide (TiO₂) and zinc oxide (ZnO) has been widely studied in various applications, including organic pollutant remediation in aqueous systems. The popularity of these materials is based on their high photocatalytic activity, strong photosensitivity, and relatively low cost. However, their commercial application has been limited by their wide bandgaps, inability to absorb visible light, fast electron/hole recombination, and limited recyclability since the nanomaterial is difficult to recover. Researchers have developed several strategies to overcome these limitations. Chief amongst these is the coupling of different semi-conductor materials to produce heterojunction nanocomposite materials, which are both visible-light-active and easily recoverable. This review focuses on the advances made in the development of magnetic ferrite-based titanium oxide and zinc oxide nanocomposites. The physical and magnetic properties of the most widely used ferrite compounds are discussed. The spinel structured material had superior catalytic and magnetic performance when coupled to TiO₂ and ZnO. An assessment of the range of synthesis methods is also presented. A comprehensive review of the photocatalytic degradation of various priority organic pollutants using the ferrite-based nanocomposites revealed that degradation efficiency and magnetic recovery potential are dependent on factors such as the chemical composition of the heterojunction material, synthesis method, irradiation source, and structure of pollutant. It should be noted that very few studies have gone beyond the degradation efficiency studies. Very little information is available on the extent of mineralization and the subsequent formation of intermediate compounds when these composite catalysts are used. Additionally, potential degradation mechanisms have not been adequately reported.

Several anthropological studies on policy in Africa have highlighted discrepancies between the conception, implementation and outcome of development projects. Using my case study, which is drawn from an ethnographic research conducted between 2011 and 2012 in central Mozambique, I demonstrate the post-colonial government policy contradiction in relation to land and how this has been influencing the way livelihoods discourses, plans and projects led by the government and NGOs are designed. My findings show how the land lease policy is a continuous factor that structures local land use and livelihoods across the twentieth and twenty-first centuries and has fuelled a growing demand for land and conflicts. I argue that official policy and local practices differ since the power of discourses has been unable to shape reality.