An introduction by the guest editor to a selection of papers from the 10th European Meeting on Solar Chemistry & Photocatalysis: Environmental Applications - SPEA10

This special issue of Photochemical & Photobiological Sciences includes a selection of papers presented at the 10th European Meeting on Solar Chemistry & Photocatalysis: Environmental Applications – SPEA10, held at the “Palacio de Exposiciones y Congresos” Almería (Spain) between 4th and 8th of June, 2018.

The European Meeting on Solar Chemistry and Photocatalysis: Environmental Applications (SPEA) started in 2000. The first meeting was held in Saint-Avoid (France) with no more than 40 participants, the second also in Saint-Avoid and later in Barcelona and Las Palmas de Gran Canaria (Spain), Palermo (Italy), Prague (Czech Republic), Porto (Portugal), Thessaloniki (Greece) and Strasbourg (France), with a periodicity of two years. With each new conference the number of attendees and the range of countries represented has grown reaching more than 350 participants in Strasbourg and a similar number in Almería, at SPEA10. 44 countries covering all continents were present at SPEA10. Therefore, the SPEA Meeting has become mature due to the efforts of many research groups organizing different events and many high level researchers who supported SPEA with their regular attendance throughout the years.

The conference program was subdivided into eighteen focused sessions, addressing the following main areas of current research in the field of Solar Chemistry and Photocatalysis: photocatalytic, photochemical and photosynthetic systems for H₂ production and CO₂ utilization; photocatalytic hybrid systems; water treatment; water disinfection; experimental standardization and commercial applications; photocatalytic membranes and thin films; novel materials for photochemistry and photocatalysis; modelling and mechanistic studies in photochemistry and photocatalysis; green synthesis by photochemistry and photocatalysis; air treatment. Five plenary speakers gave more detailed insights into different key aspects of Solar Chemistry and Photocatalysis, namely: photocatalysis for organic synthesis, graphene as photocatalyst for solar fuels production, environmental and economic impact of photocatalysis, solar water disinfection (SODIS) and heterogeneous photocatalysis in the gas phase.

In addition to the plenary lectures, the scientific program included 85 regular oral presentations, 250 poster contributions which were discussed during the whole conference, and highlighted 36 doctoral student works within 3 flash oral sessions. The present collection includes articles dealing with new semiconductor photocatalysts, wastewater phototreatment, photoassisted inactivation of pathogens, water splitting by photoelectrochemical processes and CO₂ photoreduction. Although not exhaustive, the selection reflects the excellent perspectives for application of the processes described. The next paragraph briefly summarizes these contributions.

The photocatalytic degradation of phthalates and other emerging pollutants was studied not only for suspended TiO₂ or TiO₂ films in glass, but also by Zn–CeO and dye-sensitization, including anoxic photocatalytic treatment of mining wastewater and process intensification by a combination with ozone. Bioaerosol photocatalytic inactivation by TiO₂-coated glass rings was the objective of one study. Photo-oxidative and photo-reductive capabilities of ilmenite-rich (iron) black sands was studied using model contaminants. The theme of photocatalytic transformation for energy production through reduction was addressed by new photocatalysts for photoelectrochemical water splitting or for gas-phase CO₂ reduction. Water disinfection was considered using UV/persulfate.

The invited editor wishes to express his appreciation to all the authors for their contributions to this special issue and thank the editorial staff of Photochemical & Photobiological Sciences for assistance. Sixto Malato wishes to thank the Spanish Ministry of Economy and Competitiveness financial support under the “Acciones de Programación Conjunta Internacional 2017” Programme (Reference: PCIN-2017-005).

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