In this work, a visible-light-driven plasmonic Ag–ZnO nanohybrid photocatalyst was prepared by a one-pot approach with the aim of tailoring its structural, electronic and photocatalytic properties. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV-vis optical diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy and electron spin resonance (ESR) spectroscopy. The effects of silver loading on the electronic structure and photodegradation of a rhodamine B dye solution were investigated experimentally and theoretically. It was found that the Ag–ZnO nanohybrid showed an enhanced photocatalytic activity for the degradation of the rhodamine B dye solution under visible-light irradiation and the photocatalytic performance was optimized at an Ag/Zn molar ratio of 0.05. The enhancement of the photocatalytic activity was attributed to the effective charge transfer from the plasmon-excited Ag nanoparticles to ZnO, which suppresses the charge recombination during the photocatalytic process. Optionally, the effective recycling of the photocatalyst was achieved by visible light illumination, free of secondary environmental contamination. This work may provide a new insight into the design and preparation of advanced ZnO-based visible-light photocatalytic materials.

The release of heavy metals during coal combustion may pose potential hazards to the surrounding environment and human health. In this study, we investigated the migration characteristics and ecological risks of heavy metals during the combustion of two distinct raw coal samples (C1 and C2) sourced from Shanxi Province. The analytical results demonstrate significant differences in volatilization behavior between the samples, with total heavy metal release rate ranging from 30.25% to 98.92% for C1 and from 17.77 to 98.16% for C2. Four elements—Cd, As, Pb, and Hg—exhibited preferential migration to fly ash fractions A1 and A2, displaying higher transfer coefficients compared to other monitored heavy metals. Chemical speciation analysis revealed that elemental release behavior was predominantly governed by residual phases (2.2–81.4%), Fe-Mn oxide-bound forms (3.7–45.6%), and sulfate-associated fractions (1.3–56.8%). Combustion temperature showed nonlinear positive correlations with the volatilization rates of Cd, As, Pb, and Hg. Hg volatilization decreases at a combustion temperature below 600 °C, whereas for Cd, As, and Pb, this temperature is below 800 °C. Ecological risk indices (RI) indicate substantial contamination potential in fly ash matrices: A1 (RI = 285.32) is dominated by Hg (I_geo = 1.9, $E_r^i$ = 224) with a notable contribution from Cd ($E_r^i$ = 51), whereas A2 (RI = 246.67) showed a predominance of Cd (I_geo = 1.6, $E_r^i$ = 138) over Hg ($E_r^i$ = 94.4). These findings underscore the need for optimized combustion parameters and enhanced particulate filtration systems to mitigate environmental impacts associated with coal-fired power generation.

C₅H₆O₃N₂, monoclinic, P2₁/c (no. 14), a = 11.3451(10) Å, b = 4.9505(5) Å, c = 10.3200(8) Å, β = 99.220(3)°, V = 572.12(9) ų, Z = 4, R _gt (F) = 0.0429, wR _ref (F ²) = 0.1031, T = 170 K.

Complete desorption of contaminants from electrode materials is required for the efficient utilization and long service life of capacitive deionization (CDI) but remains a major challenge. The electrodesorption capacity of CDI in the conventional electrode configuration is limited by the narrow electrochemical stability window of water, which lowers the operating potential to approximately 1.2 V. Here, we report a graphite anode–titanium cathode electrode configuration that extends the cathode potential to −1.7 V and provides an excellent (100%) electrodesorption performance, which is maintained after five cycles. The improvement of the cathode potential depends on the redox property of the electrode. The stronger the oxidizability of the anode and reducibility of the cathode, the wider the cathode potential. The complete desorption potential of SO₄²⁻ predicted by theoretical electrochemistry was the foundation for optimizing the electrode configuration. The desorption efficiency of Cl⁻ depended on the ionic strength and was negligibly affected by circulating velocities above 112 mL min⁻¹. This work can direct the design optimizations of CDI devices, especially for reactors undergoing chemisorption during the electrosorption process.