We devise simple and readily scaleable photochemical methods to synthesize silver nanostructures of varying size, morphologies, and optical properties using batch and flow strategies.

Antimicrobial materials are gaining significant interest as awareness of pathogens spread through contact becomes increasingly prevalent. While various compounds with antibacterial properties have been explored as active ingredients in such materials, many are prone to leaching, leading to undesirable risks to the environment and to human health. Herein, we develop and test a multilayered plastic film filled with silver nanoparticles, long known to be potent antibacterial agents, supported in a silica matrix. Cross-linked methacrylate layers on both sides of these nanostructures prevent leaching even after several uses, making the material essentially benign. Furthermore, we derive silica from rice husk, an abundant and affordable agricultural waste product. Our findings demonstrate that initial irradiation of the material with UVA light facilitates the photothermal migration of nanoparticles towards the material’s surface, thereby significantly enhancing its antimicrobial properties. Remarkably, after just 5 min of visible light irradiation, the material exhibits over 99.999% inhibition of bacterial growth. This environmentally friendly plastic composite harnesses visible light to actively combat bacteria, providing an exciting proof-of-concept for future applications in antimicrobial coatings.

The kinetics of the interaction of several cannabinoids with singlet oxygen have been examined in acetonitrile solution using laser flash photolysis techniques and using xanthone as a singlet oxygen sensitizer. Typical rate constants for these Type 2 reactions are in the 1–7 × 10 ⁷ M ⁻¹ s ⁻¹ range and are in accordance with typical reactivities for phenolic compounds. Protection of the phenolic function reduces the reactivity by approximately a factor of five, thus confirming that singlet oxygen quenching is dominated by the phenolic group.

The United Nations and the World Health Organization provide clear guidelines to ensure water security for urban and rural populations. Common contaminants include bacteria and a variety of organic contaminants, such as medications and agricultural runoff. The rapid advancement of point-of-use water treatment is crucial to align with these international recommendations. While some problems are chronic and require long-term solutions, others are transient contamination issues that occur without warning and frequently lead to boil water advisories that can last for extended periods. In these cases, providing reliable water security requires solutions that can be deployed rapidly, are affordable, and can be implemented at the point of use with minimal operator training. Our research explores the state of the art in photocatalysis as a method for purifying water from organic contaminants and bacteria. We present a comparative analysis of various catalysts, supports, and light sources, along with our perspective on the benefits of flow systems. Practical solutions require flow techniques that are portable and can address at least the recommended survival requirements of ~7.5 L per capita per day for small communities, schools, or small hospitals. In this perspective, we propose that flow-compatible modified TiO₂ catalysts can offer practical solutions implemented with either solar light or LED sources in the UVA or visible region.

We report an efficient method for the testing of multiple potential photocatalysts designed for the removal of volatile organic compounds (VOC) from contaminated air. The method is based on the facile deposition of films of catalytic powders on the walls of standard crimp vials and the introduction of small amounts of contaminants under a gas atmosphere of choice. The samples are rotated under a suitable light source, such as UVA lamps, and are analyzed by GC–MS following dissolution in a convenient carrier solvent. The catalyst‐treated vials can be reused, and multiple vials can be irradiated simultaneously. This strategy allows numerous catalytic materials, contaminants, and condition variations to be screened in a short time, upward of 20 samples per day.