Significantly Accelerated Photochemical Perfluorooctanoic Acid Decomposition at the Air-Water Interface of Microdroplets.

The efficient elimination of per- and polyfluoroalkyl substances (PFASs) from the environment remains a huge challenge and requires advanced technologies. Herein, we demonstrate that perfluorooctanoic acid (PFOA) photochemical decomposition could be significantly accelerated by simply carrying out this process in microdroplets. The almost complete removal of 100 and 500 μg/L PFOA was observed after 20 min of irradiation in microdroplets, while this was achieved after about 2 h in the corresponding bulk phase counterpart.

Automatic Identification of Individual Nanoplastics by Raman Spectroscopy Based on Machine Learning.

The increasing prevalence of nanoplastics in the environment underscores the need for effective detection and monitoring techniques. Current methods mainly focus on microplastics, while accurate identification of nanoplastics is challenging due to their small size and complex composition. In this work, we combined highly reflective substrates and machine learning to accurately identify nanoplastics using Raman spectroscopy.

Imaging of pH distribution inside individual microdroplet by stimulated Raman microscopy.

Aerosol microdroplets as microreactors for many important atmospheric reactions are ubiquitous in the atmosphere. pH largely regulates the chemical processes within them; however, how pH and chemical species spatially distribute within an atmospheric microdroplet is still under intense debate. The challenge is to measure pH distribution within a tiny volume without affecting the chemical species distribution.

Dense Arrays of Nanohelices: Raman Scattering from Achiral Molecules Reveals the Near-Field Enhancements at Chiral Metasurfaces.

Against the background of the current healthcare and climate emergencies, surface enhanced Raman scattering (SERS) is becoming a highly topical technique for identifying and fingerprinting molecules, e.g., within viruses, bacteria, drugs, and atmospheric aerosols.

Significantly Accelerated Hydroxyl Radical Generation by Fe(III)-Oxalate Photochemistry in Aerosol Droplets.

Fe(III)-oxalate complexes are ubiquitous in atmospheric environments, which can release reactive oxygen species (ROS) such as HO, O, and OH under light irradiation. Although Fe(III)-oxalate photochemistry has been investigated extensively, the understanding of its involvement in authentic atmospheric environments such as aerosol droplets is far from enough, since the current available knowledge has mainly been obtained in bulk-phase studies. Here, we find that the production of OH by Fe(III)-oxalate in aerosol microdroplets is about 10-fold greater than that of its bulk-phase counterpart.

Strategies and Challenges of Identifying Nanoplastics in Environment by Surface-Enhanced Raman Spectroscopy.

Nanoplastics (<1000 nm) have been evidenced to be universal in a variety of environmental media. They pose a potential cytotoxicity and health risk due to their tiny size, which allows them to easily penetrate biological barriers and enter cells. Here, we briefly review the various prevalent analytical techniques or tools for identifying nanoplastics, and further move to focus on their advantages and disadvantages.

A protocol to study microdroplet photoreaction at an individual droplet level using in situ micro-Raman spectroscopy.

Photochemical synthesis and photocatalysis in droplet microreactors represent promising approaches to relieve the global energy and environmental crises. Here, we describe a protocol for studying microdroplet photoreaction at an individual droplet level based on in situ micro-Raman spectroscopy. We provide details of superhydrophobic substrate preparation, microdroplets generation, photoreactions performing, and data analyses.

Ultrasound-boosted selectivity of CO in CO electrochemical reduction.

Among the possible products of CO electrochemical reduction, CO plays a unique and vital role, which can be an ideal feedstock for further reduction to C products, and also the important component of syngas that can be used as feedstock for value-added chemicals and fuels. However, it is still a challenge to tune the CO selectivity on Cu electrode. Here we newly construct an ultrasound-assisted electrochemical method for CO reduction, which can tune the selectivity of CO to CO from less than 10% to >80% at -1.

New insights into the role of sulfite in BiOX photocatalytic pollutants elimination: In-operando generation of plasmonic Bi metal and oxygen vacancies.

Photocatalysis has been regarded as a sustainable strategy for wastewaters remediation, and sulfite addition could significantly accelerate the photocatalytic performances. However, the related mechanisms are still not well understood. Here, we for the first time found that plasmonic Bi and oxygen vacancies were in-operando generated on BiOX (X = Cl, Br, I) in the presence of sulfite under light irradiation.

Surface-Enhanced Raman Spectroscopy Facilitates the Detection of Microplastics <1 μm in the Environment.

Micro- and nanoplastics are considered one of the top pollutants that threaten the environment, aquatic life, and mammalian (including human) health. Unfortunately, the development of uncomplicated but reliable analytical methods that are sensitive to individual microplastic particles, with sizes smaller than 1 μm, remains incomplete. Here, we demonstrate the detection and identification of (single) micro- and nanoplastics by using surface-enhanced Raman spectroscopy (SERS) with Klarite substrates.

Optimizing nanocarbon shell in zero-valent iron nanoparticles for improved electron utilization in Cr(VI) reduction.

A core-shell structured zero-valent iron@carbon (ZVI@C) nanocompoiste was designed to improve the electron utilization of ZVI in the Cr(VI) reduction. The porosity of carbon layer in ZVI@C was optimized for improving the efficiency of electron utilization of ZVI in the Cr(VI) reduction process. The porous structure of carbon layer was controllably synthesized by adjusting the carbon source and the ratio of C/Fe in the precursor.