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Since the successful isolation of a one atom thick, two-dimensional graphene layer by Novoselov and Geim in 2004, numerous new graphene synthesis methods have been proposed. Graphite oxide, with its tunable physicochemical properties, is an important precursor material in graphene production. The most commonly applied graphite oxide synthesis procedure, known as the Hummers method, involves an acidic, wet chemical oxidation of graphite. Substantial amounts of concentrated sulphuric acid and potassium permanganate are required in this method, posing serious environmental and safety hazards. In this master thesis research, photocatalytic graphite oxidation is investigated as sustainable alternative synthesis route towards graphite oxide. Highly oxidative species are produced through UV illumination of an anatase TiO2 photocatalyst layer. These reactive molecules introduce oxygen-containing functionalities on the graphite surfaces leading to photocatalytically obtained graphite oxide. Preliminary experiments examined the structural and morphological changes of natural and synthetic graphite (HOPG) upon photo-oxidation. Raman spectroscopy results confirmed the introduction of sp3 hybridised carbon networks in the sp2 dominating graphite lattice. A new sandwich deposition configuration, in which a central graphite layer is surrounded by two TiO2 layers, was proven to successfully oxidise the sp2 carbon. A configuration with graphite deposited above the TiO2 layer led to be the most efficient photo-oxidation as a result of the high graphite oxidation degree in combination with high carbon recovery. Furthermore, the increasing intensity ratio ID/IG with increasing water vapour (H2O) concentrations indicated the importance of hydroxyl radicals in the oxidative gas mixture. SEM and AFM measurements of photo-oxidised graphite revealed drastic morphological and topographical modifications such as deep surface holes and large bumps. Photo-oxidation resulted in the formation of elevated oxidation-induced islands, which are believed to be an initial state of surface blister formation. Blisters arise due to oxidative species causing intercalation and subsurface gas evolution. AFM measurements of remotely photo-oxidised HOPG demonstrated a distinct phase image contrast, increased RMS surface roughness and large blister heights, confirming the synthesis of highly oxidised graphite. For the first time, remote HOPG photo-oxidation with thin ALD prepared TiO2 films confirmed the ability of photo-oxidised species to diffuse through the gas phase for initiating graphite oxidation. Additionally, the photocatalytic activity of this ALD TiO2 was maintained as shown by sequential graphite oxidations. A self-customised Al radical quencher roughly led to a patterned graphite substrate surface, which will allow precise chemical tailoring in the long term. Also, TiO2 powder self-synthesised by a modified sol-gel method, has been proven photocatalytically active. Finally, oxygen-containing surface functionalities were held responsible for the decreased thermal stability of photo-oxidised natural graphite.