Solar‐driven CO2 reduction reaction (CO2RR) is largely constrained by the sluggish mass transfer and fast combination of photogenerated charge carriers. Herein, we find that the photocatalysis CO2RR efficiency at the abundant gas-liquid interface provided by microdroplets is two orders of magnitude higher than that of the corresponding bulk phase reaction. Even in the absence of sacrificial agents, the production rate of HCOOH over WO3·0.33H2O mediated by microdroplets reaches 2536.23 μmol h-1g-1 (vs. 13.32 μmol h-1g-1 in bulk phase), which is significantly superior to the previously reported photocatalysis CO2RR in bulk phase water. Beyond the efficient delivery of CO2 to photocatalyst surfaces within microdroplets, we reveal that the strong electric field at the gas-liquid interface of microdroplets essentially promotes the separation of photogenerated electron-hole pairs. A scalable HCOOH photocatalysis production is further demonstrated by using an electric nebulizer to generate a large number of microdroplets. This study provides a deep understanding of ultrafast reaction kinetics mediated by the gas-liquid interface of microdroplets and a novel way of addressing the low efficiency of photocatalytic CO2 reduction.

People of all ages consume salt every day, but is it really just salt? Plastic nanoparticles (nanoplastics) polluting the oceans and the atmosphere are posing an increasing environmental threat and have begun to contaminate everyday salt in consumer goods. Herein, we developed a combined Surface Enhanced Raman Scattering (SERS) and Stimulated Raman Scattering (SRS) approach that can simultaneously realize the filtration, enrichment, and detection of nanoplastics in commercial salt. SERS was used to explore the potential types of nanoplastic contaminants in salts. SRS was used to conduct imaging and to quantify the presence of nanoplastics. Nanoplastics in sea salts produced from different sources were studied, with the following nanoplastics detected: polystyrene (PS), polyethylene (PE), polypropylene (PP). We estimate that, depending on location, an average person could be ingesting as many as 63,100 nanoplastics per year through the consumption of sea salt alone. Nanoplastics can readily adsorb organic matter and heavy metal particles, so the potential harm to human health should not be underestimated.