Interfacial Electronic Interactions Promoted Activation for Nitrate Electroreduction to Ammonia over Ag-Modified Co3O4.

Electrocatalytic nitrate (NO3 -) reduction to ammonia (NRA) offers a promising pathway for ammonia synthesis. The interfacial electronic interactions (IEIs) can regulate the physicochemical capabilities of catalysts in electrochemical applications, while the impact of IEIs on electrocatalytic NRA remains largely unexplored in current literature. In this study, the high-efficiency electrode Ag-modified Co3O4 (Ag1.5Co/CC) is prepared for NRA in neutral media, exhibiting an impressive nitrate conversion rate of 96.86 %, ammonia Faradaic efficiency of 96.11 %, and ammonia selectivity of ~100 %. Notably, the intrinsic activity of Ag1.5Co/CC is ~81 times that of Ag nanoparticles (Ag/CC). Multiple characterizations and theoretical computations confirm the presence of IEIs between Ag and Co3O4, which stabilize the CoO6 octahedrons within Co3O4 and significantly promote the adsorption of reactants (NO3 -) as well as intermediates (NO2 - and NO), while suppressing the Heyrovsky step, thereby improving nitrate electroreduction efficiency. Furthermore, our findings reveal a synergistic effect between different active sites that enables tandem catalysis for NRA: NO3 - reduction to NO2 - predominantly occurs at Ag sites while NO2 - tends to hydrogenate to ammonia at Co sites. This study offers valuable insights for the development of high-performance NRA electrocatalysts.

Quercetin-loaded PLGA nanoparticles coating with macrophage membranes for targeted delivery in acute liver injury.

Quercetin (QU), a natural flavonoid with potent anti-inflammatory and antioxidant properties, holds promise in treating acute liver injury (ALI). Nonetheless, its limited solubility hampers its efficacy, and its systemic distribution lacks targeting, leading to off-target effects. To address these challenges, we developed macrophage membrane-coated quercetin-loaded PLGA nanoparticles (MVs-QU-NPs) for active ALI targeting. The resulting MVs-QU-NPs exhibited a spherical morphology with a clear core-shell structure. The average size and zeta potential were assessed as 141.70 ± 0.89 nm and -31.83 ± 0.76 mV, respectively. Further studies revealed sustained drug release characteristics from MVs-QU-NPs over a continuous period of 24 h. Moreover, these MVs-QU-NPs demonstrated excellent biocompatibility when tested on normal liver cells. The results of biodistribution analysis in ALI mice displayed the remarkable ALI-targeting ability of MVs-DiD-NPs, with the highest fluorescence intensity observed in liver tissue. This biomimetic approach combining macrophage membranes with nanoparticle delivery, holds great potential for targeted ALI treatment.

Biothiol-Functionalized Cuprous Oxide Sensor for Dual-Mode Sensitive Hg2+ Detection.

Hg2+ ions are one of the highly poisonous heavy metal ions in the environment, so it is urgent to develop rapid and sensitive detection platforms for detecting Hg2+ ions. In this work, a novel electrochemical and photoelectrochemical dual-mode sensor (l-Cys-Cu2O) was successfully fabricated, and the sensor exhibits a satisfactory detection limit (0.2 and 0.01 nM) for the detection of Hg2+, which is far below the dangerous limit of the U.S. Environmental Protection Agency. The linear ranges of dual-mode Hg2+ detections were 0.33-3.3 and 0.17-1.33 µM, respectively. Moreover, the sensor shows desirable stability, selectivity, and reproducibility for detecting Hg2+ ions. For river water samples, the recoveries of 96.6-101.4% (electrochemical data) and 93.0-105.6% (photoelectrochemical data) were obtained, indicating that the sensor could be successfully applied in the determination of Hg2+ ions in environmental water. Therefore, the designed sensor has a potential in the trace-level detection of Hg2+ ions.

Effect of the isoelectric point of pH-responsive lignin-based amphoteric surfactant on the enzymatic hydrolysis of lignocellulose.

The isoelectric point (pI) of lignin-based surfactant is an important factor in the enhancement on the enzymatic hydrolysis of lignocellulose. In this work, lignin carboxylate (LC) and quaternary ammonium lignin carboxylates (LCQ-x, x%: the mass ratio of quaternizing agent to enzymatic hydrolysis lignin) with different isoelectric points were synthesized. LC or LCQ-x with pI significantly lower or higher than 4.8 reduced the non-productive adsorption of cellulase on lignin, but for the significant inhibitory effect on cellulase activity, their enhancements on the enzymatic hydrolysis of lignocellulose were not remarkable. However, LCQ-x with pI around 4.8 preserved the cellulase activity, and significantly reduced the non-productive adsorption of cellulase, therefore remarkably enhanced the enzymatic hydrolysis. 2 g/L LC, LCQ-40 (pI = 5.0) and LCQ-100 (pI = 9.2) increased the enzymatic digestibility of pretreated eucalyptus from 35.2% to 53.4%, 95.3% and 60.4% respectively. In addition, for the excellent pH-response performance, LCQ could be efficiently recovered after enzymatic saccharification.