PR also offers a thermodynamic advantage over photocatalytic water splitting by oxidising organic substrates such as ethylene glycol (a monomeric component of polyethylene terephthalate; PET) or glucose (a monomeric component of cellulose), giving a reforming reaction (E 0 = ~0.0 V vs. reversible hydrogen electrode (RHE)) at approximately the H2 evolution potential, as opposed to water oxidation which has a high thermodynamic (E 0 = 1.23 V vs. RHE) and kinetic energy barrier. While, in principle, PR produces CO2 as an end oxidation product, in practice, the reaction does not proceed to completion and >50% of the carbon remains as small organic products (e.g. formate) dissolved in solution and the remaining CO2 remains mineralised as CO3 under alkaline conditions, allowing for zero-carbon H2 production. PR was first demonstrated using a UV-light absorbing RuO2/TiO2/Pt photocatalyst in a sugar, starch, or cellulose substrate solution, with a more recent focus on application to a wider range of realistic waste materials, including lignocellulose, polymers such as PET, polylactic acid, and polyurethane, and food waste. Further materials development has focused on the utilisation of visible light-absorbing photocatalysts such as CdS/CdOx, carbon nitride (CNx), or carbon dots, and inexpensive co-catalysts as an alternative to noble metals such as Ni2P, MoS2, and NiO. Currently, waste photoreforming offers H2 production with a smaller carbon footprint than standard steam methane reforming, but a variety of improvements need to be made to achieve cost-competitiveness such as optimised photocatalyst durability, recyclability, and application in a variety of aqueous waste solutions, including turbid suspensions. Among these improvements, photocatalyst durability is a critical consideration, with catalyst reuse lifetimes of at least one year proposed as necessary for cost effective H2 production. CNx recycling has been deployed using three methods: magnetisation, immobilisation and as photocatalytic membranes. In the first two, CNx is directly exposed to the substrate solution for direct oxidation and reduction, whereas in photocatalytic membranes, the substrates are first removed from solution by adsorption, then subsequently oxidised by CNx photocatalysis. In general, immobilisation techniques and membranes are preferred over magnetic recovery due to lower maintenance, stability, and ease in efficient recovery from remaining waste solutions or solids. Membranes also present challenges such as fouling, oxidation damage from the photocatalyst, and scaling challenges due to their complicated production processes. Catalyst immobilisation can be performed on a variety of support materials ranging from static, macroscopic supports such as glass plates, tubes, or reactor vessel walls to free supports such as glass beads, activated carbon, or sand. In the context of PR, CNx has already been immobilised on flat glass panels as part of a flow-through reactor, reaching activities of 52 ± 3 μmol m -2 h -1 with a Ni2P cocatalyst and pre-treated PET substrate in 0.5 mol L -1 KOH. Though significant recent progress has been made on photocatalytic panel systems, slurry-based systems may present a more scalable and economic approach enabled by improved light penetration and mass transfer, allowing higher photon conversion efficiency. Among free supports suitable for application in a slurry system, floating materials have gained attention due their enhanced light harvesting, gas exchange, and recovery resulting from catalyst concentration at the surface of the solution. Already explored for water treatment, floating composites make use of robust, low-density support materials such as expanded perlite, fly ash cenospheres, hollow glass microspheres, and polymer beads. The integration of fuel-generating catalysts with floating platforms allows for versatile and decentralised deployment scenarios, such as efficient use with turbid waste streams or enabling fuel production over open waters. To date, the scope of PR using recyclable photocatalyst composites has been limited to panel immobilisation and exploration of floating PR composites is necessary for further scaling of this technology.