Latest ArticlesThe increasing demand for energy density pushes LiCoO2 (LCO) to work at higher voltage (≥4.5 V), which brings a series of problems including detrimental phase transition and structural instability. Various elemental doping has been proven an effective strategy to improve its structure stability. However, the understanding of elemental doping homogeneity effect is not enough, whether in terms of the controllability of doping homogeneity or its complex consequences. In this work, LCO powders with different Al doping homogeneity were synthesized and tested under high voltage (≥4.5 V) in both half and full cell at room and high temperature, respectively. The results show that the Al homogeneously doped LCO showed better cycling stability and rate performance compared to the inhomogeneous LCO sample. Particularly, the discharge capacity of Al homogeneously doped LCO after 500 cycles under 4.5 V in full cells could reach 160.1 mAh/g at 1.0 C with 94.1% capacity retention. Postmortem characterization demonstrates that a better doping homogeneity favors the stability of both the bulk and interface as well as the kinetic conditions. This study provided new insights about LCO performance fading, which sheds new light on the development of high-voltage LCO products
Photodynamic therapy (PDT) is a promising cancer treatment modality owing to its high spatiotemporal selectivity and noninvasive nature. However, conventional photosensitizers (PSs) used in PDT are responsive only to visible light, which makes them unsuitable for tissue penetration. In this study, we propose a PS based on hot band absorption (HBA), which can be triggered by anti-Stokes light at 808 nm via a one-photon process. The introduction of selenium (Se) into pentamethine cyanine (Secy5) not only facilitates intersystem crossing for reactive oxygen species (ROS) production but also enhances HBA efficiency, thereby prolonging the excitation wavelength. In addition, Secy5 demonstrates excellent biocompatibility, unlike its I-substituted counterpart (Icy5), and produces not only 1O2 but also O2•−, making it a desirable candidate for treating hypoxic solid tumors. According to the results of in vivo and in vitro experiments, Secy5 can efficiently inhibit cancer cell growth via anti-Stokes activation processes, thereby providing a novel approach to design anti-Stokes excitation PSs for anticancer treatment.
Achieving selectivity in cell penetrating peptide (CPP) design is crucial to mitigate systemic toxicity and enable precise targeting based on distinct cellular phenotypes. Herein, we designed an amphiphilic peptide, L17Yp, by incorporating phosphorylated tyrosine into natural occurring M-lycotoxin peptide, known for its potent membrane-lytic activity. This strategic modification induced a conformational shift, as confirmed by circular dichroism spectroscopy, transitioning it from its bioactive α-helix conformation to an inactive random coli configuration, effectively shielding its membrane-penetrating capacity. Upon exposure to alkaline phosphatase, L17Yp undergoes enzymatic dephosphorylation, prompting a conformational shift that restores its membrane-transduction capabilities. This unique property hold promises for selective drug delivery. This work introduces an enzymatic approach for targeted perturbation of the cell membrane, offering promising prospects for precise drug delivery applications.
The utilization of fungicides in plants is very low, emphasizing the need to improve their utilization rates. In this study, the fungicide dimethachlon (Dim) was encapsulated within hollow mesoporous silica (HMSNs), and a coating was formed on the HMSNs surface through the reaction of Na2CO3 and CaCl2, resulting in a pH-responsive delivery system named D/H@CaCO3, proven valuable in preventing sclerotinia diseases in romaine lettuce. When disease-infested romaine lettuce was treated with D/H@CaCO3, it degraded in the acidic microenvironment of Sclerotinia sclerotiorum (S. sclerotiorum), allowing for the pH-responsive release of Dim and effectively killing S. sclerotiorum. Moreover, the degraded CaCO3 coating releases CO2, which enhances the photosynthetic pigment contents, such as chlorophyll a, chlorophyll b, and carotenoids, in turn promoting plant growth. D/H@CaCO3 is biologically safe for plants and is environmentally friendly, as confirmed by assessments involving zebrafish and earthworms. Given their antifungal capabilities, the controlled release of fungicides offers potential for plant protection.
Multi-stimuli responsive materials controlled and coupled by two or more channels have a broad range of applications in the field of switches, memories, and molecular machines. The exploration of the material is currently focused on the pure organic system, which limits the development of such materials greatly. In this work, we present a new chiral organic-inorganic hybrid salt, (R-3-hydroxypyrrolidinium)2[Fe(CN)5(NO)] (1), which exhibits rare multi-stimuli responsive behaviors in thermal, mechanical and optical channels. In detail, 1 undergoes a C2-P21221 phase transition deriving from the thermal motion of organic cations with the increase of temperature, but the reverse transition can only be induced by mechanical pressure. Moreover, polycrystalline hybrid salt showed photo-responsive performance, i.e., the ground-state N-bound nitrosyl ligand adopts two configurations in excited states caused by light in 532 nm irradiation, accompanying with a photo-induced structural transformation of the anionic framework. Namely, the thermal motion characteristics of organic cations, the photoresponse characteristics of anionic inorganic skeleton and the pressure characteristics from hydrogen bonds are simultaneously integrated in 1. This unprecedented coupling mechanism of multi-stimuli responses makes 1 a potential candidate for future multichannel data storage applications.
Control of subsurface interstitial atoms in transition metals is an effective approach to modulate selectivity in hydrogenation reactions. In this study, nickel was alloyed with gallium to form Ni3Ga, thereby regulating the octahedral interstitial sites. Subsequently, carbon atoms were introduced into the Ni3Ga (forming Ni3GaC0.5) via thermal treatment in an acetylene atmosphere, leading to a significant enhancement in selectivity for acetylene hydrogenation reaction. The X-ray diffraction and transmission electron microscopy results demonstrate an increase in the lattice parameter due to the incorporation of carbon atoms and the uniform distribution of carbon in Ni3GaC0.5 nanoparticles. The obtained Ni3GaC0.5/oCNT catalyst exhibits significantly improved selectivity in acetylene hydrogenation reaction, with approximately 82% ethylene selectivity at 98% conversion. Furthermore, it maintains good selectivity at various hydrogen-to-alkyne ratios and displays good stability during long-term operation. The introduction of carbon suppresses the formation of the subsurface hydrogen structure under reaction conditions. Additionally, the charge transfer between carbon and nickel results in the electron deficiency of nickel, effectively inhibiting the over-hydrogenation pathway and enhancing the selectivity. These results provide insights for the design of non-precious metal catalysts in selective hydrogenation reactions.
Multimodal bioorthogonal small molecule probes play a pivotal role in drug-focused biomedical research. However, existing drug tracking and imaging techniques face obstacles in living organisms, hindering precise drug localization and target protein capture. Herein, we introduced a multimodal probe named 1-(azidomethyl)pyrene-4,5–dione (AMPD). The probe incorporates adjacent dione structures at the pyrene core. AMPD selectively interacts with oxygen-rich alkene-labeled drug molecules under ice-blue LED light exposure, producing specific fluorescence emission and enabling in vivo tracking and flow cytometry sorting. A methyl azide group was also introduced at the pyrene core to help efficiently enrich target proteins via click chemistry with alkyne-functionalized beads. AMPD demonstrates exceptional biocompatibility, rendering it highly suitable for visual photo-triggered tracking studies. Combined with metabolic labeling using an oxygen-rich alkene-tagged drug molecule probe, AMPD is effective for live animal, tissue, cellular, and in-gel imaging, as well as target protein identification through magnetic capture. With its versatile capabilities, AMPD enhances our comprehension of drug-target interactions at the in vivo level and expedites the process of drug discovery.
The insufficient F(III)/Fe(II) cycling rate resulted from high combination of photogenerated carriers severely hinders the photo-Fenton activity. In this work, 0 dimensional α-Fe2O3 nanoclusters decorated TiO2 heterojunction (FT-x) was prepared via in-situ phase transformation strategy. FT-200 exhibited the optimal photo-Fenton activity for 2,4-dichlorophenol degradation with the kinetic rate constant reaching 1.0806 min−1 under low H2O2 dosage (1 mmol/L), which was 126.1 and 202.8 times higher than that of TiO2 and α-Fe2O3. Radical quenching experiments and electron spin resonance spectra proved that ·OH was the leading reactive specie. The enhanced photo-Fenton activity was attributed to the accelerated F(III)/Fe(II) cycling rate induced by the direct Z-Scheme charge transfer mechanism. Benefiting from the abundant ·OH production, the dechlorinate ratios and mineralization ratios of multiple chlorophenol pollutants (2,4-dichlorophenol, 4-chlorophenol, 2,4,6-trichlorophenol) all exceeded 98%. The biotoxicity of chlorophenol wastewater was greatly reduced after the treatment by Light/H2O2/FT-200 system. Overall, this work constructed a low-cost and highly efficient photo-Fenton system for refractory organic wastewater treatment.
Human β-galactosidase (β-gal) is recognized as a crucial biomarker for evaluating senescence at the cellular and tissue levels in humans. However, tools to precisely track the endogenous β-gal are still limited. Herein, we present two novel self-calibrating β-gal probes 7a and 7b which were constructed on a unique green/red dual-emissive fluorescence platform. The two probes inherently exhibited a stable green fluorescence signal impervious to β-gal activity, serving as a reliable internal reference. They also displayed a progressively diminishing red fluorescence signal with the increasing of β-gal expression levels. The dual behavior endows them with self-calibration capacity and then renders excellently selective and sensitive for precisely monitoring β-gal activity. Notably, compared with E. coli β-gal, the two probes are more effectively response to A. oryzae β-gal homologous to human β-gal, indicating their unique species-selectivity. Furthermore, 7a was validated for its effectiveness in determining senescence-associated β-galactosidase (SA-β-gal) expression in senescent NRK-52E and HepG2 cells, underscoring its practical applicability in senescence research.
The design of pnictide nonlinear optical crystals is quite different from chalcogenide and oxide those, in which a new paradigm need be developed to regulate the band gap, one of key optical parameters. In this work, two non-centrosymmetric halidepnictides, [Cd2P]2[CdBr4] (CPB) and [Cd2As]2[CdBr4] (CAB) were reported. The complete octet binding electrons of pnictogens were constructed by four Cd-P polar covalent bonds under the anchoring effect of halogens, creating an extremely flat valence band maximum with band dispersion of only 0.17 eV. As expected, the balance of the covalency and ionicity in CPB and CAB was successfully realized, leading to a wide band gap of 2.58 eV and 1.88 eV. Remarkably, CPB not only has a widest band gap among Cd-containing pnictides, but also exhibits a SHG effect of 1.2 × AgGaS2, moderate birefringence (0.088@visible light and calcd. 0.043@2050 nm) and a wide IR transmission range. This is the first time that the octet binding electrons construction strategy was utilized to design non-diamond like NLO pnictides with excellent performances.