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The pollution profiles of 25 legacy and emerging poly- and perfluoroalkyl substances (PFASs) in the estuaries along the Laizhou Bay, northern China were investigated to better understand the new structure of PFASs under international regulations and to estimate the mass loadings of PFASs in coastal rivers. About 39.87 kg/d of PFASs were discharged into the Laizhou Bay by the Xiaoqing, Mi and Zhimai Rivers. Total PFAS concentrations in the Xiaoqing River decreased notably in recent years, but were still greater than the levels in 2011. Contribution of replacement substances exhibited an increasing trend in recent years. However, the long-chain chemicals were still the larger contributors of PFASs. Perfluoromethoxypropionic acid (PFMPA) was first detected with high concentrations ranging from 165.3 to 586.3 ng/L in the Xiaoqing River. The results of this study provided baseline data for ecological risk assessment, environmental management and corresponding development of pollution treatment technology. • Perfluoromethoxypropionic acid (586.3 ng/L) was first detected in the Xiaoqing River. • Long-chain poly- and perfluoroalkyl substances were still the dominant contributors. • Pollution of poly- and perfluoroalkyl substances in the Xiaoqing River decreased. • Three study rivers discharged 39.87 kg/d of 25 poly- and perfluoroalkyl substances. [ABSTRACT FROM AUTHOR]

A fresh type of lithium-ion battery anode called high entropy oxide (HEO) has a remarkable specific capacity and outstanding cycle performance. The advantage of HEO consists in the distinct adjustable contents along with governable chemical constitution, which makes it possible to develop novel electrode materials using infinite combinations of elements. We successfully synthesized (FeCoNiCuZn) 3 O 4 material via a straightforward hydrothermal way in this work. At a lofty current density of 1 A g−1, obtaining an invertible capacity of 540 mAh g−1 behind 500 cycles, the unique structure of (FeCoNiCuZn) 3 O 4 exhibits remarkable stability. We analyzed the valence states of the metal elements and further investigated their relationship with electrochemical and kinetic properties after using X-ray photoelectron spectroscopy (XPS). Subsequently, by incorporating the (FeCoNiCuZn) 3 O 4 anode with activated carbon (AC) in a lithium-ion hybrid capacitor (LIHC), which could deliver an outstanding power density of 4000 W kg−1 and energy density of 158 Wh kg−1 while maintaining excellent capacity retention property even after 5000 cycles, the anode showed considerable performance. This is the first time HEO has been used in LIHC, as far as we are aware. [ABSTRACT FROM AUTHOR]

Fluoroquinolones (FQs) are a class of antibiotics with emerging concern. This study investigated the photochemical properties of two representative FQs, i.e., norfloxacin (NORF) and ofloxacin (OFLO). Results showed that both FQs could sensitize the photo-transformation of acetaminophen under UV-A irradiation, during which excited triplet state (3FQ*) was the main active species. In the presence of 3 mM Br‾, the photolysis rate of acetaminophen increased by 56.3% and 113.5% in the solutions with 10 μM NORF and OFLO, respectively. Such an effect was ascribed to the generation of reactive bromine species (RBS), which was verified by 3,5-dimethyl-1H-pyrazole (DMPZ) probing approach. 3FQ* reacts with acetaminophen through one-electron transfer, producing radical intermediates which then couple to each other. Presence of Br‾ did not lead to the formation of brominated products but the same coupling products, which suggests that radical bromine species, rather than free bromine, were responsible for the accelerated acetaminophen transformation. According to the identified reaction products and assisted with the theoretical computation, the transformation pathways of acetaminophen under UV-A irradiation were proposed. The results reported herein suggest that sunlight-driven reactions of FQs and Br‾ may influence the transformation of coexisting pollutants in surface water environments. [Display omitted] • FQs can sensitize the degradation of acetaminophen under UV-A irradiation. • 3FQ* is the dominant reactive species attacking acetaminophen. • 3FQ* can oxidize bromide (Br‾) to yield reactive bromine species (RBS). • Radical RBS accelerates the degradation of acetaminophen. [ABSTRACT FROM AUTHOR]

Aluminum, known as a natively abundant and trivalent charge carrier, has a high volumetric density and theoretical specific capacity. Due to these characteristics, aluminum-ion batteries are recognized as a prospective technology for large-scale energy storage in the future. However, the practical applicability of aluminum ion batteries has been hindered by the confirmed decline of the electrode host structure and the slow diffusion kinetics of aluminum ion. Here, in this work, layered NH 4 V 4 O 10 nanosheets cathode materials were first applied to the aqueous aluminum-ion battery. Thanks to the interlayer support of NH 4 +, which acts as a "pillar", the sample demonstrates a high capacity of 257.78 mA h g−1 at a current density of 0.5 A g−1 and excellent rate performance of 87.80 mA h g−1 at a current density of 5 A g−1. Besides, the evolution of electrode crystal/electronic structure and the charge compensation mechanism during Al3+ intercalation/deintercalation have been investigated through systematic experimental measurements and theoretical computations. This work is anticipated to provide fresh perspectives and more thorough insights into exploration of competent cathode material and charge storage mechanisms for aqueous aluminum-ion batteries with high electrochemical properties. [Display omitted] • Layered NH 4 V 4 O 10 nanosheet has been synthesized by a simple hydrothermal method. • NH 4 V 4 O 10 was first applied to the aqueous aluminum-ion battery as the cathode material. • The as-prepared NH 4 V 4 O 10 realizes excellent rate performance with a high capacity of 87.80 mA h g−1 at a high current density of 5 A g−1. • The mechanism of reversible removal of Al3+ was revealed by DFT calculation, XPS and XRD. [ABSTRACT FROM AUTHOR]