Tuning A-Site Cation Deficiency in Pr0.5La0.5BaCo2O5+ δ Perovskite to Realize Large-Scale Hydrogen Evolution at 2000 mA cm-2.

Industrial-level hydrogen production from the water electrolysis requires reducing the overpotential (η) as much as possible at high current density, which is closely related to intrinsic activity of the electrocatalysts. Herein, A-site cation deficiency engineering is proposed to screen high-performance catalysts, demonstrating effective Pr0.5- xLa0.5BaCo2O5+ δ (P0.5- xLBC) perovskites toward alkaline hydrogen evolution reaction (HER). Among all perovskite compositions, Pr0.4La0.5BaCo2O5+ δ (P0.4LBC) exhibits superior HER performance along with unique operating stability at large current densities (J = 500-2000 mA cm-2 geo). The overpotential of ≈636 mV is achieved in P0.4LBC at 2000 mA cm-2 geo, which outperforms commercial Pt/C benchmark (≈974 mV). Furthermore, the Tafel slope of P0.4LBC (34.1 mV dec-1) is close to that of Pt/C (35.6 mV dec-1), reflecting fast HER kinetics on the P0.4LBC catalyst. Combined with experimental and theoretical results, such catalytic activity may benefit from enhanced electrical conductivity, enlarged Co-O covalency, and decreased desorption energy of H* species. This results highlight effective A-site cation-deficient strategy for promoting electrochemical properties of perovskites, highlighting potential water electrolysis at ampere-level current density.

Defect-Rich Glassy IrTe2 with Dual Enzyme-Mimic Activities for Sono-Photosynergistic-Enhanced Oncotherapy.

The complexity, diversity, and heterogeneity of malignant tumors pose a formidable challenge for antitumor therapy. To achieve the goal of significantly enhancing the antitumor effect, nanomedicine-based synergistic therapy is one of the important strategies. Herein, we innovatively report a defect-rich glassy IrTe2 (G-IrTe2) with weak Ir-Te bond strength for synergistic sonodynamic therapy (SDT), chemodynamic therapy (CDT), and mild photothermal therapy (PTT). G-IrTe2 sonosensitizer under ultrasound (US) stimuli exhibits excellent reactive oxygen species (ROS) production performance. Besides, catalase (CAT)-like activity of G-IrTe2 can provide abundant oxygen to enhance the SDT effect. Then, the theoretical calculation verifies that US stimuli can easily make the irregular Ir-Te bond to be broken in amorphous IrTe2 and free electrons will be released to combine with the oxygen and further form singlet oxygen (1O2). Meanwhile, G-IrTe2 with peroxidase (POD)-like activity can also catalyze endogenous H2O2 to produce more ROS for chemodynamic therapy (CDT), which is conducive to better tumor ablation. Furthermore, the ROS produced by sono-/chemodynamic processes can cause mitochondrial dysfunction and further give rise to heat shock protein (HSP) downregulated expression, maximizing the efficiency of mild PTT. Therefore, such glassy IrTe2 with rich defect could be significantly involved in synergistic oncotherapy and then effectively achieve outstanding antitumor efficacy. This study provides a new research idea for expanding the application of inorganic glassy nanomaterials in promoting the therapeutic effect of tumors.

Multi-enzyme Co-expressed Dual-Atom Nanozymes Induce Cascade Immunogenic Ferroptosis via Activating Interferon-γ and Targeting Arachidonic Acid Metabolism.

Immunotherapy is currently the most promising treatment strategy for long-term tumor regression. However, current cancer immunotherapy shows low response rates due to insufficient immunogenicity of tumor cells. Herein, we report a strategy to keep tumor cells highly immunogenic by triggering cascade immunogenic tumor ferroptosis. We developed a six-enzyme co-expressed nanoplatform: lipoxygenase (LOX) and phospholipase A2 (PLA2)-co-loaded FeCo/Fe-Co dual-metal atom nanozyme (FeCo/Fe-Co DAzyme/PL), which can not only induce initial immunogenic tumor ferroptosis through its own multi-enzyme mimetic activities but also up-regulate arachidonic acid (AA) expression to synergize with CD8+ T cell-derived IFN-γ to induce ACSL4-mediated immunogenic tumor ferroptosis. During this process, FeCo/Fe-Co DAzyme/PL can induce lipid peroxidation (LPO) by efficiently generating reactive oxygen species (ROS) and depleting GSH and GPX4 at tumor sites. Additionally, free AA released from PLA2 catalysis is converted into arachidonyl-CoA under the activation of ACSL4 stimulated by IFN-γ, which is further incorporated into phospholipids on membranes and peroxidized with the participation of LOX. Consequently, FeCo/Fe-Co DAzyme/PL can promote irreversible cascade immunogenic ferroptosis through multiple ROS storms, GSH/GPX4 depletion, LOX catalysis, and IFN-γ-mediated ACSL4 activation, constructing an effective pathway to overcome the drawbacks of current immunotherapy.

A Novel Near-Infrared Ytterbium Complex [Yb(DPPDA)2](DIPEA) with Φ = 0.46% and τobs = 105 µs.

The luminescent performances of near-infrared (NIR) lanthanide (Ln) complexes were restricted greatly by vibration quenching of X-H (X = C, N, O) oscillators, which are usually contained in ligands and solvents. Encapsulating Ln3+ into a cavity of coordination atoms is a feasible method of alleviating this quenching effect. In this work, a novel ytterbium complex [Yb(DPPDA)2](DIPEA) coordinated with 4,7-diphenyl-1,10-phenanthroline-2,9-dicarboxylic acid (DPPDA) was synthesized and characterized by FT-IR, ESI-MS and elemental analysis. Under the excitation of 335 nm light, [Yb(DPPDA)2](DIPEA) showed two emission peaks at 975 and 1011 nm, respectively, which were assigned to the characteristic 2F5/2 → 2F7/2 transition of Yb3+. Meanwhile, this ytterbium complex exhibited a plausible absolute quantum yield of 0.46% and a luminescent lifetime of 105 µs in CD3OD solution. In particular, its intrinsic quantum yield was calculated to be 12.5%, and this considerably high value was attributed to the near-zero solvent molecules bound to Yb3+ and the absence of X-H oscillators in the first coordination sphere. Based on experimental results, we further proposed that the sensitized luminescence of [Yb(DPPDA)2](DIPEA) occurred via an internal redox mechanism instead of an energy transfer process.

Synthesis and Near Infrared Luminescence Properties of a Series of Lanthanide Complexes with POSS Modified Ligands.

A polyhedral oligomeric silsesquioxanes (POSS) modified 8-hydroxyquinoline derivative (denoted as Q-POSS) was synthesized and used as a ligand to coordinate with lanthanide ions to obtain a series of lanthanide complexes Ln(Q-POSS)3 (Ln = Er3+, Yb3+, Nd3+). The as-prepared lanthanide complexes have been characterized by FT-IR, UV⁻Vis, and elemental analysis. All these complexes showed the characteristic near-infrared (NIR) luminescence originated from the corresponding lanthanide ions under excitation. Compared with the unmodified counterparts LnQ3 (HQ = 8-hydroxyquinoline), the Ln(Q-POSS)3 complexes showed obviously increased emission intensity, which was ascribed mainly to the steric-hindrance effects of the POSS moiety in the ligands. It is believed that the POSS group could suppress undesired excimer formation and intermolecular aggregation, thus decreasing the concentration quenching effect of the corresponding lanthanide complexes.

Global identification of O-GlcNAc transferase (OGT) interactors by a human proteome microarray and the construction of an OGT interactome.

O-Linked ß-N-acetylglucosamine (O-GlcNAcylation) is an important protein PTM, which is very abundant in mammalian cells. O-GlcNAcylation is catalyzed by O-GlcNAc transferase (OGT), whose substrate specificity is believed to be regulated through interactions with other proteins. There are a handful of known human OGT interactors, which is far from enough for fully elucidating the substrate specificity of OGT. To address this challenge, we used a human proteome microarray containing ~17,000 affinity-purified human proteins to globally identify OGT interactors and identified 25 OGT-binding proteins. Bioinformatics analysis showed that these interacting proteins play a variety of roles in a wide range of cellular functions and are highly enriched in intra-Golgi vesicle-mediated transport and vitamin biosynthetic processes. Combining newly identified OGT interactors with the interactors identified prior to this study, we have constructed the first OGT interactome. Bioinformatics analysis suggests that the OGT interactome plays important roles in protein transportation/localization and transcriptional regulation. The novel OGT interactors that we identified in this study could serve as a starting point for further functional analysis. Because of its high-throughput and parallel analysis capability, we strongly believe that protein microarrays could be easily applied for the global identification of regulators for other key enzymes.

Multi-Enzyme Co-Expressed Nanomedicine for Anti-Metastasis Tumor Therapy by Up-Regulating Cellular Oxidative Stress and Depleting Cholesterol.

Tumor cells movement and migration are inseparable from the integrity of lipid rafts and the formation of lamellipodia, and lipid rafts are also a prerequisite for the formation of lamellipodia. Therefore, destroying the lipid rafts is an effective strategy to inhibit tumor metastasis. Herein, a multi-enzyme co-expressed nanomedicine: cholesterol oxidase (CHO) loaded Co─PN3 single-atom nanozyme (Co─PN3 SA/CHO) that can up-regulate cellular oxidative stress, disrupt the integrity of lipid rafts, and inhibit lamellipodia formation to induce anti-metastasis tumor therapy, is developed. In this process, Co─PN3 SA can catalyze oxygen (O2 ) and hydrogen peroxide (H2 O2 ) to generate reactive oxygen species (ROS) via oxidase-like and Fenton-like properties. The doping of P atoms optimizes the adsorption process of the intermediate at the active site and enhances the ROS generation properties of nanomedicine. Meantime, O2 produced by catalase-like catalysis can combine with excess cholesterol to generate more H2 O2 under CHO catalysis, achieving enhanced oxidative damage to tumor cells. Most importantly, cholesterol depletion in tumor cells also disrupts the integrity of lipid rafts and inhibits the formation of lamellipodia, greatly inhibiting the proliferation and metastasis of tumor cells. This strategy by up-regulating cellular oxidative stress and depleting cellular cholesterol constructs a new idea for anti-metastasis-oriented cancer therapy strategies.

Engineering a hollow bowl-like porous carbon-confined Ru-MgO hetero-structured nanopair as a high-performance catalyst for ammonia borane hydrolysis.

Exploration of high-performance catalysts holds great importance for on-demand H2 production from ammonia borane (AB) hydrolysis. In this work, a hollow bowl-like porous carbon-anchored Ru-MgO hetero-structured nano-pair with high-intensity interfaces is made, using a tailored design approach. Consequently, the optimized catalyst shows AB hydrolysis activity with a turnover frequency value of 784 min-1 in aqueous media and 1971 min-1 in alkaline solvent. Robust durability is also achieved, with slight deactivation after a ten-cycle test. Combined experimental and theoretical calculations validate the positive function of the interface between Ru and MgO for facilitating H transfer and boosting water activation, thus leading to improved AB hydrolysis performance. This study could be valuable in guiding the upgradation of Ru catalytic systems, to advance their practical applications.

Programmed Targeting Pyruvate Metabolism Therapy Amplified Single-Atom Nanozyme-Activated Pyroptosis for Immunotherapy.

Increasing cellular immunogenicity and reshaping the immune tumor microenvironment (TME) are crucial for antitumor immunotherapy. Herein, this work develops a novel single-atom nanozyme pyroptosis initiator: UK5099 and pyruvate oxidase (POx)-co-loaded Cu-NS single-atom nanozyme (Cu-NS@UK@POx), that not only trigger pyroptosis through cascade biocatalysis to boost the immunogenicity of tumor cells, but also remodel the immunosuppressive TME by targeting pyruvate metabolism. By replacing N with weakly electronegative S, the original spatial symmetry of the Cu-N4 electron distribution is changed and the enzyme-catalyzed process is effectively regulated. Compared to spatially symmetric Cu-N4 single-atom nanozymes (Cu-N4 SA), the S-doped spatially asymmetric single-atom nanozymes (Cu-NS SA) exhibit stronger oxidase activities, including peroxidase (POD), nicotinamide adenine dinucleotide (NADH) oxidase (NOx), L-cysteine oxidase (LCO), and glutathione oxidase (GSHOx), which can cause enough reactive oxygen species (ROS) storms to trigger pyroptosis. Moreover, the synergistic effect of Cu-NS SA, UK5099, and POx can target pyruvate metabolism, which not only improves the immune TME but also increases the degree of pyroptosis. This study provides a two-pronged treatment strategy that can significantly activate antitumor immunotherapy effects via ROS storms, NADH/glutathione/L-cysteine consumption, pyruvate oxidation, and lactic acid (LA)/ATP depletion, triggering pyroptosis and regulating metabolism. This work provides a broad vision for expanding antitumor immunotherapy.

Semiconducting polymer dots doped with europium complexes showing ultranarrow emission and long luminescence lifetime for time-gated cellular imaging.

Bright dots: Semiconducting polymer dots (Pdots) doped with europium complexes possess line-like fluorescence emission, high quantum yield, and long fluorescence lifetime. The Pdots successfully labeled receptors on cells. The long fluorescence lifetime of the Pdots was used to distinguish them from other red fluorescence emitting nanoparticles, and improve the signal-to-noise ratio for time-gated cellular imaging. PVK=poly(9-vinylcarbazole).

Alloyed Mn-Cu-In-S nanocrystals: a new type of diluted magnetic semiconductor quantum dots.

A new type of Mn-Cu-In-S diluted magnetic semiconductor quantum dots was synthesized and reported for the first time. The quantum dots, with no highly toxic elements, not only show the same classic diluted magnetic behavior as Mn-doped CdSe, but also exhibit tunable luminescent properties in a relatively large window from 542 to 648 nm. An absolute photoluminescence quantum yield up to 20% was obtained after the shell growth of ZnS. This kind of magnetic/luminescent bi-functional Mn-Cu-In-S/ZnS core/shell quantum dot might serve as promising nanoprobes for use in dual-mode optical and magnetic resonance imaging techniques.

Hollow nanoparticles synthesized via Ostwald ripening and their upconversion luminescence-mediated Boltzmann thermometry over a wide temperature range.

Upconversion nanoparticles (UCNPs) with hollow structures exhibit many fascinating optical properties due to their special morphology. However, there are few reports on the exploration of hollow UCNPs and their optical applications, mainly because of the difficulty in constructing hollow structures by conventional methods. Here, we report a one-step template-free method to synthesize NaBiF4:Yb,Er (NBFYE) hollow UCNPs via Ostwald ripening under solvothermal conditions. Moreover, we also elucidate the possible formation mechanism of hollow nanoparticles (HNPs) by studying the growth process of nanoparticles in detail. By changing the contents of polyacrylic acid and H2O in the reaction system, the central cavity size of NBFYE nanoparticles can be adjusted. Benefiting from the structural characteristics of large internal surface area and high surface permeability, NBFYE HNPs exhibit excellent luminescence properties under 980 nm near-infrared irradiation. Importantly, NBFYE hollow UCNPs can act as self-referenced ratiometric luminescent thermometers under 980 nm laser irradiation, which are effective over a wide temperature range from 223 K to 548 K and have a maximum sensitivity value of 0.0065 K-1 at 514 K. Our work clearly demonstrates a novel method for synthesizing HNPs and develops their applications, which provides a new idea for constructing hollow structure UCNPs and will also encourage researchers to further explore the optical applications of hollow UCNPs.

Boosting Electrochemical Carbon Dioxide Reduction on Atomically Dispersed Nickel Catalyst.

Single-atom catalysts (SACs) with metal-nitrogen (M-N) sites are one of the most promising electrocatalysts for electrochemical carbon dioxide reduction (ECO2R). However, challenges in simultaneously enhancing the activity and selectivity greatly limit the efficiency of ECO2R due to the improper interaction of reactants/intermediates on these catalytic sites. Herein, we report a carbon-based nickel (Ni) cluster catalyst containing both single-atom and cluster sites (NiNx-T, T = 500-800) through a ligand-mediated method and realize a highly active and selective electrocatalytic CO2R process. The catalytic performance can be regulated by the dispersion of Ni-N species via controlling the pyrolysis condition. Benefitting from the synergistic effect of pyrrolic-nitrogen coordinated Ni single-atom and cluster sites, NiNx-600 exhibits a satisfying catalytic performance, including a high partial current density of 61.85 mA cm-2 and a high turnover frequency (TOF) of 7,291 h-1 at -1.2 V vs. RHE, and almost 100% selectivity toward carbon monoxide (CO) production, as well as good stability under 10 h of continuous electrolysis. This work discloses the significant role of regulating the coordination environment of the transition metal sites and the synergistic effect between the isolated single-site and cluster site in enhancing the ECO2R performance.

Selenium Vacancy Engineering Using Bi2Se3 Nanodots for Boosting Highly Efficient Photonic Hyperthermia.

Despite bismuth-based energy conversion nanomaterials having attracted extensive attention for nanomedicine, the nanomaterials suffer from major shortcomings including low tumor accumulation, long internal retention time, and undesirable photothermal conversion efficiency (PCE). To combat these challenges, bovine serum albumin and folic acid co-modified Bi2Se3 nanomedicine with rich selenium vacancies (abbreviated as VSe-BS) was fabricated for the second near-infrared (NIR-II) light-triggered photonic hyperthermia. More importantly, selenium vacancies on the crystal planes (0 1 5) and (0 1 11) of VSe-BS with similar formation energies could be distinctively observed via aberration-corrected scanning transmission electron microscopy images. The defect engineering endows VSe-BS with enhanced conductivity, making VSe-BS possess outstanding PCE (54.1%) in the NIR-II biowindow and desirable photoacoustic imaging performance. Tumor ablation studies indicate that VSe-BS possesses satisfactory therapeutic outcomes triggered by NIR-II light. These findings give rise to inspiration for further broadening the biological applications of defect engineering bismuth-based nanomaterials.

Two-step relaxation in a linear tetranuclear dysprosium(III) aggregate showing single-molecule magnet behavior.

A well-defined two-step relaxation, described by the sum of two modified Debye functions, is observed in a new alkoxido-bridged linear tetranuclear Dy(III) aggregate showing single-molecule magnet behavior with a remarkably large energy barrier. This compound represents a model molecular aggregate with a clear two-step relaxation evidenced by frequency-dependent susceptibility, which therefore may stimulate further investigations regarding the relaxation dynamics of lanthanide-based systems.

Novel multifunctional nanocomposites: magnetic mesoporous silica nanospheres covalently bonded with near-infrared luminescent lanthanide complexes.

In this paper, we report the fabrication and characterization of magnetic mesoporous silica nanospheres covalently bonded with near-infrared (NIR) luminescent lanthanide complexes [denoted as Ln(DBM)(3)phen-MMS (Ln = Nd, Yb)]. Ln(DBM)(3)phen-MMS (Ln = Nd, Yb) nanospheres with an average size of 80-130 nm were synthesized via incorporation of the chelate ligand 5-[N,N-bis-3-(triethoxysilyl)propyl]ureyl-1,10-phenanthroline (phen-Si) into the framework of magnetic mesoporous silica (denoted as phen-MMS), followed by introduction of the Ln(DBM)(3)(H(2)O)(2) (Ln = Nd, Yb) complexes into the nanocomposites via a ligand exchange reaction. The morphological, structural, textural, magnetic, and NIR luminescent properties were well-characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), N(2) adsorption-desorption, a superconducting quantum interference device (SQUID), and photoluminescence spectra. These nanocomposites, which possess high surface area, high pore volume, and well-defined pore size, exhibit two-dimensional hexagonal (P6mm) mesostructures. After ligand-mediated excitation, Ln(DBM)(3)phen-MMS (Ln = Nd, Yb) nanocomposites exhibit the characteristic NIR emission of Nd(3+) and Yb(3+), respectively. Magnetic measurements reveal that these mulfunctional nanocomposites possess superparamagnetic properties at 300 K. The high magnetization values make the nanocomposites respond to the external magnetic field quickly. Additionally, the results indicate that Nd(DBM)(3)phen-MMS nanocomposites may have potential applications for laser systems or the optical amplifiers operating at 1.3 microm and Yb(DBM)(3)phen-MMS nanocomposites have several advantages for potential applications in drug delivery or optical imaging.

Three p-tert-butylthiacalix[4]arene-supported cobalt compounds obtained in one pot involving in situ formation of N6H2 ligand.

Three p-tert-butylthiacalix[4]arene (H(4)TC4A)-supported Co(II) compounds, [Co(4)(TC4A)(N(3))(4)(N(6)H(2))(CH(3)OH)](CH(3)OH)(2) (1), [Co(8)(TC4A)(2)(N(3))(2)(N(6)H(2))(2)(CH(3)COO)(4)(CH(3)OH)(4)](OH)(2)(CH(3)OH)(4) (2), and [Co(10)(TC4A)(4)(N(3))(4)](CH(3)OH)(4) (3), have been solvothermally obtained in one pot and structurally characterized by single-crystal X-ray diffraction analyses, powder XRD, and IR spectroscopy. This work presents the first one-dimensional (1) cobalt cluster for the calixarene complexes and another two octanuclear (2) or decanuclear (3) cobalt clusters. In the structures of compounds 1 and 2, a novel N(6)H(2) ligand formed by the in situ (2 + 3) cycloaddition of two azides was observed. Density functional theory (DFT) calculations give the heat of formation (2N(3)(-) + 2H(+) --> N(6)H(2)) and decomposition energy (N(6)H(2) --> 3N(2) + H(2)) of 677.47 and 124.85 kcal/mol, respectively. Furthermore, an intergradation was determined at the B3LYP/6-311++g(d,p) level for the formation of the N(6)H(2) ligand. In addition, one TC4A ligand of a sandwich unit adopts a cone conformation, while the other adopts a pinched cone conformation in 3. The magnetic properties of these three compounds were influenced mainly by the orbital contributions of the distorted octahedral Co(II) ions.

Constructing an ultra-adsorbent based on the porous organic molecules of noria for the highly efficient adsorption of cationic dyes.

A novel Noria-POP-1 material has been successfully synthesized by the simple polymerization of the porous organic molecules of noria and aryl diamines. Noria-POP-1 displayed excellent adsorption capacity for cationic dyes from water with selective removal ability. The adsorption experiments show that Noria-POP-1 displays a remarkable capability to selectively adsorb and separate methylene blue with an adsorption capacity of 2434 mg g-1, which is the highest value obtained so far for porous organic polymers.

Bismuthene for highly efficient carbon dioxide electroreduction reaction.

Bismuth (Bi) has been known as a highly efficient electrocatalyst for CO2 reduction reaction. Stable free-standing two-dimensional Bi monolayer (Bismuthene) structures have been predicted theoretically, but never realized experimentally. Here, we show the first simple large-scale synthesis of free-standing Bismuthene, to our knowledge, and demonstrate its high electrocatalytic efficiency for formate (HCOO-) formation from CO2 reduction reaction. The catalytic performance is evident by the high Faradaic efficiency (99% at -580 mV vs. Reversible Hydrogen Electrode (RHE)), small onset overpotential (<90 mV) and high durability (no performance decay after 75 h and annealing at 400 °C). Density functional theory calculations show the structure-sensitivity of the CO2 reduction reaction over Bismuthene and thicker nanosheets, suggesting that selective formation of HCOO- indeed can proceed easily on Bismuthene (111) facet due to the unique compressive strain. This work paves the way for the extensive experimental investigation of Bismuthene in many different fields.

Author Correction: Bismuthene for highly efficient carbon dioxide electroreduction reaction.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.