Highlights Anthropogenic pollution has continuously increased since the industrial revolution.  Nanoparticles can provide solutions to in situ cleanup challenges.  Nano-objects are increasingly being deployed in the field since the 2000s.  Their use is not exempt of limitations (aggregation, human health risks). 5 Their slow development in Europe is also due to economic motives and regulatory issues.  Questions concerning toxicity and migration into the matrices need to be answered.Highlights (for review : 3 to 5 bullet points (maximum 85 characters including spaces per bullet point)

A modular molecular hybrid colloidal photocatalyst composed by TiO2 nanocrystals (TiO2-NCs) as light-absorber and the molecular complex [Ru(tda)(pypyr)2], Ru-tda, as a water oxidation catalyst precursor, both anchored onto Single-Walled Carbon Nanotubes (SWCNTs) is described. This colloidal molecular hybrid photocatalyst, labeled as Rutda/SWCNT/TiO2-NCs, is a robust material that can be easily prepared and scaled up. At neutral pH, in the presence of 3 suns illumination, the molecular hybrid material Rutda/SWCNT/TiO2-NCs is capable of achieving the photocatalytic oxidation of water to dioxygen in the presence of persulfate, giving an unprecedented turnover number (TON) of 229.

Emerging pollutants such as pharmaceuticals are of special concern because despite their low environmental concentration, their biological activity can be intense, and they should be prevented to reach uncontrolledly to the environment. A graphene-based hybrid material decorated with Fe3O4 and TiO2 nanoparticles (NPs) has been prepared to effectively remove emerging pollutants as nonsteroidal anti-inflammatory drugs (NSAIDs) Ibuprofen and Diclofenac present in water at low environmental concentrations by a one-step functionalization process following a novel gentle and scalable surfactant depletion approach. Following this methodology, nanoparticles are progressively deprived of their original surfactant in the presence of graphene, leading to the formation of hybrid nanostructures composed of two different types of nanoparticles well dispersed over the graphene nanosheets. Ibuprofen and Diclofenac adsorption kinetics on the composites was investigated via UV-Vis spectroscopy. The as prepared hybrid material possesses high adsorption capacity, superparamagnetic properties, photocatalytic behavior, and good water dispersibility. Thanks to incorporating TiO2 nanoparticles as in situ catalysts, the adsorption performance of composites is restored after use, which could be a promising recycling pathway for the adsorbents in wastewater treatments.