Lixia Zhao

A hydrocyclone-assisted strategy is developed to construct core–shell ZrO ₂ /ZnIn ₂ S ₄ heterojunctions, enabling effective IEF and bandgap engineering for enhanced photocatalytic performance, with the underlying mechanism systematically investigated.

Given the widespread overuse and intricate toxicological features of different antibiotics, developing advanced optical sensors for synchronous analysis of multiple antibiotics is significant but still a challenge. Multiemissive material-based optical sensors possess great potential in detecting structurally similar compounds. However, an efficient and universal strategy to construct multiemissive materials is still scarce. Herein, an energy barrier strategy is utilized to achieve full-spectrum tunable multiemissions from a single lanthanide metal-organic framework (MOF). Using Eu/Tb-MOF as a model, another lanthanide ion acting as the "energy barrier" is introduced into the Eu/Tb-MOF to regulate the energy transfer process of the ligand. This approach enables the preparation of a series of isostructural Gd_xTb_yEu_z-NTB MOFs (NTB= 4,4',4″-nitrilotribenzoic acid), whose luminescent colors can be flexibly tuned across the whole color gamut under a single excitation wavelength. The universality of the strategy is validated by choosing other blue-emissive ligands and introducing other energy barrier ions. It is demonstrated that as long as the energy levels of the ligand and the barrier ion are appropriate, the tunable multiemissions can be obtained in a single Ln-MOF. Furthermore, the analytical performance of Gd_xTb_yEu_z-NTB MOFs for multiple antibiotics is investigated by assembling a sensor array. Two types of antibiotics (four nitrofurans and four tetracyclines) are selected as the model analytes. Detailed fingerprint information is outputted through differential interactions between each luminescent center and each antibiotic. The eight antibiotics are well-discriminated, with no cross interference even in real water samples. Moreover, the sensor array exhibits great potential in quantitative detection of antibiotics with high sensitivity (detection limit as low as 0.03 μM). Our work provides valuable guidance for constructing multiemissive materials and their application in antibiotic discrimination, stimulating further exploration of advanced optical materials.

Spontaneous generation of reactive oxygen species (ROS) driven by water‐solid contact electrification was a new source of redox chemistry. However, superoxide radicals (O₂^•−), a kind of ROS that was of great significance in both natural and engineering environments, remain overlooked and poorly understood at the water‐solid interface. Here, we found O₂^•− could be generated spontaneously when water collided with the solid interface even under dark conditions, and its production was quantified by CL. ¹⁸O isotope labelling experiments and solid–liquid contact electrification detection confirmed that the generation of O₂^•− was from the reduction of dissolved oxygen by electrons at the water‐solid interface and that the kinetic energy of the water energized the reaction. Given the ubiquitous nature of solid–liquid collisions, such as rain colliding with mineral surfaces during rainfall, we further systematically investigated the O₂^•− generation and their decay kinetics at three distinct rain‐mineral interfaces. Results showed that O₂^•− generation ranged from 0.015 to 1.1 nM, comparable to the O₂^•− production by photochemical pathways. Our findings established the water‐solid collision interface as a previously unrecognized global source of O₂^•− and highlight a universal yet overlooked physicochemical mechanism underpinning multiphase redox chemistry.

Spontaneous generation of reactive oxygen species (ROS) driven by water‐solid contact electrification was a new source of redox chemistry. However, superoxide radicals (O₂^•−), a kind of ROS that was of great significance in both natural and engineering environments, remain overlooked and poorly understood at the water‐solid interface. Here, we found O₂^•− could be generated spontaneously when water collided with the solid interface even under dark conditions, and its production was quantified by CL. ¹⁸O isotope labelling experiments and solid–liquid contact electrification detection confirmed that the generation of O₂^•− was from the reduction of dissolved oxygen by electrons at the water‐solid interface and that the kinetic energy of the water energized the reaction. Given the ubiquitous nature of solid–liquid collisions, such as rain colliding with mineral surfaces during rainfall, we further systematically investigated the O₂^•− generation and their decay kinetics at three distinct rain‐mineral interfaces. Results showed that O₂^•− generation ranged from 0.015 to 1.1 nM, comparable to the O₂^•− production by photochemical pathways. Our findings established the water‐solid collision interface as a previously unrecognized global source of O₂^•− and highlight a universal yet overlooked physicochemical mechanism underpinning multiphase redox chemistry.

Singlet oxygen (¹O₂) is a classical nonradical reactive oxygen species (ROS), which is of great significance in both natural and engineering environments. Here, we found that ¹O₂ can be generated spontaneously at the air-water interface of microdroplets under dark conditions. ¹⁸O isotope labeled O₂ (¹⁸O₂) and water (H₂¹⁸O) were used to identify the source and formation pathway of ¹O₂ and previously reported ROS produced in microdroplets. The results showed that ¹O₂ and superoxide anions (•O₂^-) were sourced from O₂, •OH was sourced from H₂O, while H₂O₂ can be produced from both H₂O and O₂. Moreover, the excited hydrated electron (e^-(aq)) induced indirect energy transfer is responsible for exciting O₂ from the ground state to the singlet state. The findings of this work provide an important complement to the construction of a complete ROS chemistry in microdroplets.

Infectious inflammation remains a major global health issue, so novel strategies to alleviate inflammatory responses are urgently required. Cinnabar (α-HgS) used in traditional Chinese medicine shows protective effects against inflammation, but low anti-inflammatory efficacies ascribed to poor solubility and bioavailability have hindered extensive applications of cinnabar. Nanoscale chirality provides chances to improve efficacies through enantiomer-dependent interactions between cells and chiral cinnabar nanoparticles (HgSNPs). Herein HgSNPs with intrinsically wavelike chirality were prepared through a one-pot seedless method, exhibiting efficacious alleviation of inflammation in vitro and in vivo by HgSNPs with laevorotatory chirality (l-HgSNPs) rather than those with dextrorotatory chirality (d-HgSNPs). The mitogen-activated protein kinase as a crucial pathway involved in inflammation and immunity was directly blocked by l-HgSNPs through inhibition of p38 phosphorylation, so the levels of pro-inflammatory cytokines were reduced significantly. This study showed an enantiomer-dependent immunological response to chiral HgSNPs, providing a novel protocol to efficaciously modulate health risks from infectious inflammation.

Phenol photocatalytic degradation typically relies on the consumption of oxidative species such as H₂O₂. In this study, we found the persistent H₂O₂ generation promoted by the phenol photocatalytic degradation process over flower‐like ZnIn₂S₄ under visible light. The H₂O₂ generation efficiency achieved 626 µmol·g⁻¹·h⁻¹, which was 5.35 times higher than in pure water, whereas the phenol degradation efficiency was 97.34%. Experimental and theoretical analysis showed that H₂O₂ was generated via a two‐electron O₂ reduction reaction over ZnIn₂S₄. Meanwhile, phenol was attacked by the photogenerated holes which facilitated H₂O₂ production. More interestingly, phenol degradation process can also promote the H₂O₂ generation, in which hydroquinone (HQ), as the key intermediate, played an important role in promoting the persistent generation of H₂O₂. This work provided new insights into the in‐situ production of H₂O₂ accompanied with the purification of contaminated water.

The rational design of BiOBr photocatalysts with optimized surface properties and enhanced photooxidative capacities is crucial. This study proposes a synergistic strategy combining hydroxyl-rich solvents with polyvinylpyrrolidone (PVP) surfactants to modulate the structural and electronic properties of BiOBr through a solvothermal approach. The resulting self-assembled microspheres demonstrated exceptional efficiency in degrading ciprofloxacin (CIP), methyl orange (MO), and rhodamine B (RhB). Among the synthesized variants, BiOBr-EG-PVP (fabricated with ethylene glycol and PVP) exhibited the highest photocatalytic activity, achieving near-complete removal of 20 mg/L CIP and RhB within 10 min under visible light irradiation, with degradation rates 60.12–101.73 times higher than pristine BiOBr. The structural characterization revealed that ethylene glycol (EG) not only induced the formation of self-assembled microspheres but also introduced abundant surface hydroxyl groups, which simultaneously enhanced the hole-mediated oxidation capabilities. The incorporation of PVP further promoted the development of hierarchical honeycomb-like microspheres and synergistically enhanced both the hydroxyl group density and photooxidative potential through interfacial engineering. Density functional theory (DFT) calculations confirmed that the enhanced photooxidative performance originated from an increased surface oxygen content. This work elucidates the synergistic effects of hydroxyl-rich solvents and surfactant modification in the fabrication of advanced BiOBr-based photocatalysts, providing new insights for high-performance photocatalysis for environmental remediation.

Luminol-based chemiluminescence (CL) systems, as a powerful tool for bioanalysis, are limited owing to their weak CL intensity and self-decomposition of the classic oxidant H₂O₂. Herein, we introduced a new luminol CL enhancer, the natural light-driven photocatalyst MIL-100(Fe)/TiO₂, for the selective determination of dopamine (DA). By employing MIL-100(Fe)/TiO₂ for the first time as an efficient enhancer, the MIL-100(Fe)/TiO₂-luminol CL intensity was 100 times higher than that of the classical H₂O₂-luminol system. The CL spectrum, UV-vis absorption spectroscopy, radical scavenger experiments, and electron spin resonance spectroscopy were utilized to investigate the possible CL mechanism of the MIL-100(Fe)/TiO₂-luminol system. All of the results indicated that MIL-100(Fe)/TiO₂ can generate reactive oxygen species under mild natural light, which could react rapidly with the luminol anion radical and result in direct CL emission. The sensitive plate for DA was developed based on its inhibiting effect on CL intensity, and the linear range between CL intensity and DA concentration was 100 nM-1000 μM with a detection limit of 16.7 μM (S/N = 3). This study successfully achieved a stable reactant that can directly trigger the CL of luminol without the need for additional oxidizing agents under mild natural light and offers new possibilities for photoinduced amplification technology.