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A one-pot redox route is developed for simultaneous syntheses of Ag nanoparticles on MoO(sub 3) nanofibers. Four different synthetic reactions integrated into the one-pot synthesis include the oxidation of [Na(H(sub 2)O)(sub 2)]0.25MoO(sub 3) bronze, reduction of silver ions, and the in situ simultaneous growth of self-organized Ag nanoparticles and the MoO3 nanofibers.

A family of inorganic-organic hybrid vanadium selenites with zero, one-, two-, and three-dimensional structures, (1,10-phen)2V2SeO7, (2,2'-bipy)VSeO4, (4,4'-bipy)V2-Se2O8, and (4,4'-bipy)2V4Se3O15.H2O were synthesized and analyzed hydrothermally by single-crystal X-ray diffraction.

Understanding the structure-performance relationships of a frustrated Lewis pair (FLP) at the atomic level is key to yielding high efficiency in activating chemically "inert" molecules into value-added products. A sound strategy was developed herein through incorporating oxygen defects into a Zr-based metal-organic layer (Zr-MOL-D) and employing Lewis basic proximal surface hydroxyls for the in situ formation of solid heterogeneous FLP (Zr 4-δ -V O -Zr -OH ). Zr-MOL-D exhibits a superior CO 2 to CO conversion rate of 49.4 μmol g -1 h -1 in water vapor without any sacrificing agent or photosensitizer, which is about 12 times higher than that of pure MOL (Zr-MOL-P), with extreme stability even after being placed for half a year. Theoretical and experimental results reveal that the introduction of FLP converts the process of the crucial intermediate COOH* from an endothermic reaction to an exothermic spontaneous reaction. This work is expected to provide new prospects for developing efficient MOL-based photocatalysts in FLP chemistry through a sound defect-engineering strategy.

Photocatalytic reduction of CO 2 into valuable chemicals or fuels is considered a promising solution to mitigate the energy crisis. In this work, efficient CO 2 to CO conversion was achieved, accompanied by a class of trinuclear Fe clusters as photocatalysts. Under optimal conditions, the highest catalytic rate could be up to 140.9 μmol/h in 6 h with the assistance of photosensitizers (PS). The trinuclear Fe Clusters can be used as secondary building units to construct Fe-based metal-organic frameworks (MOFs). However, the catalytic activity of Fe-based MOFs is weaker than that of clusters in both the cases of extra PS-assisted MOFs and integrated PS into MOFs. The simpler synthesis, lower cost, and higher catalytic activity make the Fe clusters a better catalyst. Additionally, steady-state fluorescence tests confirmed the transfer of photogenerated electrons from PS to the clusters during the photocatalytic reaction.

It is of great importance to understand the relationship between the structure and properties at the atomic level, which provides a solid platform for the design of efficient heterogeneous catalysts. However, it remains a challenge to elucidate the roles of the structure of reaction sites in the catalytic activity of active sites due to the lack of understanding of the structure of specific active site species. Herein, taking the metal-organic framework (MOF) UiO-66(Zr) as a prototype, MOF catalysts with all-solid-state frustrated Lewis pairs (FLPs) Zr 3+ -OH were synthesized in situ by adding acetic acid (HAc) as a modulator. By introducing missing linkers, UiO-66(Zr) first becomes a visible-light-responsive photocatalyst for CO 2 reduction. The in situ Fourier transform infrared (FTIR) spectrum reveals that b-CO 3 2- is the key intermediate for the activation of CO 2 molecules through FLPs Zr 3+ -OH. Moreover, defective UiO-66(Zr) could "self-breath" by surface hydroxyls. This finding not only provides a new avenue for utilizing UV-responsive MOFs by defect engineering but also sheds light on its catalytic activity at the atomic level.

The influence of defects on quantitative carrier dynamics is still unclear. Therefore, full-spectrum responsive metallic ZnIn 2 S 4 (V In -rich-ZIS) rich in indium vacancies and exhibiting high CO 2 photoreduction efficiency was synthesized for the first time. The influence of the defects on the carrier dynamic parameters was studied quantitatively; the results showed that the minority carrier diffusion length ( L D ) is closely related to the catalytic performance. In situ infrared spectroscopy and theoretical calculations revealed that the presence of indium vacancies lowers the energy barrier for CO 2 to CO conversion via the COOH* intermediate. Hence, the high rate of CO evolution reaches 298.0 μmol g -1 h -1 , a nearly 28-fold enhancement over that with ZnIn 2 S 4 (V In -poor-ZIS), which is not rich in indium vacancies. This work fills the gaps between the catalytic performance of defective photocatalysts and their carrier dynamics and may offer valuable insight for understanding the mechanism of photocatalysis and designing more efficient defective photocatalysts.

Reprograming the N 6-methyladenosine (m 6 A) landscape is a promising therapeutic strategy against recalcitrant leukemia. In this study, we synthesized gold nanorods (GNRs) of different aspect ratios using a binary surfactant mixture of hexadecyltrimethylammonium bromide and sodium oleate. Following surface functionalization with chitosan and a 12-mer peptide, GNRa-CSP12 measuring 130 × 21 nm 2 was selectively taken up by leukemia cells via targeted endocytosis. Low doses of GNRa-CSP12 inhibited the growth of leukemia cells by disrupting the redox balance and inducing ferroptosis. Mechanistically, GNRa-CSP12 abrogated endogenous Fe 2+ -dependent m 6 A demethylase activity, which led to global m 6 A hypomethylation and post-transcriptional regulation of downstream genes that are involved in glycolysis, hypoxia, and immune checkpoint pathways. In addition, combination treatment with GNRa-CSP12 and tyrosine kinases inhibitors (TKIs) synergistically obviated the m 6 A-mediated TKI resistance phenotype. Finally, GNRa-CSP12 as a potential immunotherapeutic agent could enhance immunotherapy outcome in leukemia. Our preclinical findings provide the proof-of-concept for targeting m 6 A-methylation-based epitranscriptomics using nanoparticle as an "epigenetic drug" for cancer therapy.

Cell-membrane-coated nanoparticles have emerged as a promising antitumor therapeutic strategy. However, the immunologic mechanism remains elusive, and there are still crucial issues to be addressed including tumor-homing capacity, immune incompatibility, and immunogenicity. Here, we reported a tumor-associated macrophage membrane (TAMM) derived from the primary tumor with unique antigen-homing affinity capacity and immune compatibility. TAMM could deplete the CSF1 secreted by tumor cells in the tumor microenvironment (TME), blocking the interaction between TAM and cancer cells. Especially, after coating TAMM to upconversion nanoparticle with conjugated photosensitizer (NPR@TAMM), NPR@TAMM-mediated photodynamic immunotherapy switched the activation of macrophages from an immunosuppressive M2-like phenotype to a more inflammatory M1-like state, induced immunogenic cell death, and consequently enhanced the antitumor immunity efficiency via activation of antigen-presenting cells to stimulate the production of tumor-specific effector T cells in metastatic tumors. This TAM-membrane-based photodynamic immunotherapy approach offers a new strategy for personalized tumor therapy.

As a multiple proton-coupled electron transfer process, photocatalytic conversion of CO 2 usually produces a wide variety of products. Improving the yield and selectivity of CO 2 to the single product is still a significant challenge. In this work, we describe that the rationally constructed W 18 O 49 /Cu 2 O{111} interfaces achieve highly selective CO 2 photocatalytic conversion to CH 4 . In situ Fourier transform infrared spectroscopy measurements reveal that the formation of W 18 O 49 /Cu 2 O{111} interfaces restrains the desorption of CO* intermediates in CO 2 photocatalytic conversion. UPS spectra, PL spectra, and photocurrent curves show that more photogenerated electrons are excited and transferred to W 18 O 49 /Cu 2 O{111} interfaces. All of these play critical roles in CH 4 production. As an outcome, the yield rate of CO 2 photocatalytic conversion to CH 4 was enhanced from 6.5 to 17.20 μmol g -1 h -1 with selectivity as high as 94.7%. The work demonstrates the feasibility and versatility of interface engineering in achieving highly selective CO 2 photocatalytic conversion.

Herein, we present a facile colloidal method to synthesize the high-quality AgGaS 2 nanocrystals (NCs) within 2 min via exploiting the high-reactivity S precursor and then extend this synthetic strategy to the preparation of AgGaS 2 /ZnS core-shell NCs by a one-pot method without prior purification of AgGaS 2 core. The as-synthesized samples were structurally characterized to confrim the formation of AgGaS 2 /ZnS core-shell NCs. The energy band gap of the AgGaS 2 /ZnS NCs can be effectively tunable from 2.98 to 2.83 eV by the control of their nonstoichiometry and further continuously decreases to 1.90 eV by the preparation of alloyed AgGa x In 1- x S 2 /ZnS NCs (1 ≤ x ≤ 0). Benefitting from the efficient band gap modulations, the photoluminescence (PL) colors of the AgGaS 2 -based NCs can cover almost the whole visible region from blue (460 nm) to red (671 nm). Our work demonstrates the one-pot synthesis of AgGaS 2 /ZnS core-shell NCs and their band gap engineering, which is of crucial in scalability toward industrial application and in tailoring optical characteristics of I-III-VI 2 materials.

The combination of ferroelectric-optical properties in halide perovskites has attracted tremendous interess because of its potential for optoelectronic and energy applications. However, very few reports focus on the ferroelectricity of all-inorganic halide perovskites quantum dots. Herein, we report a excellent ferroelectricity in CsPbBr 3 quantum dots (QDs) with a saturation polarization of 0.25 μC/cm 2 . Differential scanning calorimetry, X-ray diffraction, and transmission electronic microscopy revealed that the mechanism of ferroelectric-paraelectric switching of CsPbBr 3 QDs can be attributed to the phase transition from cubic phase ( Pm 3̅ m ) to the orthorhombic phase ( Pna2 1 ). In the orthorhombic CsPbBr 3, the distortion of octahedral [PbBr 6 ] 4- structural units and the off-center Cs + generated the slightly separated centers of positive charge and negative charge, resulting in the ferroelectric properties. The variable-temperature emission spectrum from 328 to 78 K exhibits green luminescence and a gradual red shift due to the phase transition. This finding opens up an avenue to explore the ferroelectric-optical properties of inorganolead halide perovskites for high-performance multifunctional materials.

The synthesis of intermetallic antimonides usually depends on either the high-temperature alloying technique from high-purity metals or the flux method in highly poisonous Pb-melt. In this paper, we introduced a soft-chemical method to synthesize intermetallic antimonides from ternary chalcogenide precursors under an argon atmosphere below 200 °C. Powder X-ray diffraction and compositional analysis clearly indicate that a new phase of the Ag 3 Sb nanocrystal was synthesized from the Ag 3 SbS 3 precursors. Three types of trialkylphosphines (TAPs) were applied as desulfurization agents, and the transformation mechanism was elucidated. The capability of the desulfurization agent follows the sequence of triphenylphosphine (TPP) > tributylphosphine (TBP) > trioctylphosphine (TOP). Besides, this TAP-driven desulfurization route to synthesize the intermetallic phase could also be possible for AgSbSe 2 and Sb 2 S 3 . Therefore, this paper provides an efficient and mild technique for the fabrication of intermetallic nanocrystals.

Spinel Co 3 O 4 , consisting of two mixed valence states, Co 2+ and Co 3+ , has attracted enormous interest as a promising electrocatalyst for oxygen evolution reaction (OER). Proper control on the relative proportion of Co 2+ /Co 3+ in cobalt oxide can greatly tune the electronic structure and further optimize its catalytic performance. Herein, a hybrid coupling Co 3 O 4 with black phosphorus (Co 3 O 4 @BP) is designed as an efficient catalyst for OER. Electron migration from BP to Co 3 O 4 is achieved in Co 3 O 4 @BP, owing to the higher Fermi level of BP than that of Co 3 O 4 . Efficient electron transfer can not only create massive active sites with abundant Co 2+ but also remarkably suppress the deterioration of BP. Particularly, the Co 3 O 4 @BP catalyst outperforms the pristine Co 3 O 4 by over four times and is even 20 times higher than that of bare BP at a potential of 1.65 V versus reversible hydrogen electrode. Our finding provides insightful understanding for electronic engineering in Co 3 O 4 @BP by balancing advantages and utilizing drawbacks of Co 3 O 4 and BP.

Ni 3 S 2 nanosheets doped with tin (Sn) grown on nickel foam (Sn-Ni 3 S 2 /NF) through a facile hydrothermal process were found to be superior water-splitting electrocatalysts. As for overall water splitting (OWS), when the current density is 10 mA cm -2 , the required voltage is only 1.46 V. Meanwhile, it exhibits a large current density property and long-time stability (>60 h current-time tests) for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). In order to reach the current densities of 100 and 1000 mA cm -2 , Sn-Ni 3 S 2 /NF needs overpotentials of 0.17 and 0.57 V for HER, and 0.27 and 0.58 V for OER, respectively. The water-splitting property of Sn-Ni 3 S 2 /NF is much better than that of pure Ni 3 S 2 /NF or even 20 wt % Pt/C/NF and RuO 2 /NF. Furthermore, Sn-Ni 3 S 2 /NF showed a higher turnover frequency at different potentials, with ∼100% Faraday efficiency for both O 2 and H 2 . The improved activity of Sn-Ni 3 S 2 /NF activity for water-splitting is attributed to the doping of Sn, which enhanced the intrinsic activity of Sn-Ni 3 S 2 /NF for OWS. This article not only provides a new efficient and stable catalyst for OWS, but also proposes an interface design principle for NF-based high-performance water-splitting materials.

Mn 4 CaO 5 cluster in green plant is considered as the ideal structure for water oxidation catalysis. However, this structure is difficult to be constructed in heterogeneous catalyst because of its distorted spatial structure and unique electronic state. Herein, we report the synthesis of two-dimensional biomimetic Ca-Mn-O catalyst with Mn 4 CaO 5 clusterlike structure through ultrasonic-assisted reduction treatment toward Ca-birnessite. The synergistic effect between ultrasonic and reduction successfully reduced the Mn oxidation state in Ca-birnessite without breaking the structure of MnO 2 monolayers, forming a regular two-dimensional structure with Mn 4 CaO 5 cubanelike structure unit for the first time. The biomimetic catalyst shows a superior water oxidation activity (turnover frequency = 3.43 s -1 ), which is the best in manganese-based heterogeneous catalyst to date. This work provides a new strategy for the precise synthesis of specific structure and exhibits a great prospect of biomimic in heterogeneous catalyst.

We present a simple and cost-effective molten salt synthetic route toward phase-pure perovskite cobaltite microcrystallines and successfully regulate different crystal facets for perovskite LaCoO 3 by the strong interaction between Cl - anions and Sr 2+ cations in molten salt system and polar plane. We then take LaCoO 3 (100 and 110), LaCoO 3 (111), and La 0.7 Sr 0.3 CoO 3 (111) as comparison models, and we characterize their crystal structure, morphology, composition, electronic state, and catalytic properties. X-ray photoelectron spectroscopy (XPS) shows that the prepared samples with high-energy (111) crystal facets contain more surface oxygen species and active Co ions than La enrichment perovskite LaCoO 3 (110 and 100) on the surface. Furthermore, combining with ambient-pressure XAS, valence band spectroscopy, and density functional calculations, we find that exposed high-energy (111) crystal facets and doping Sr ions can enhance the hybridization between Co cations and O anions and their O p-band center is closer to the Fermi level, compared with that of LaCoO 3 (100 and 110). As expected, the samples with high-energy (111) crystal facets show better CO oxidation activity than LaCoO 3 (100 and 110), and La 0.7 Sr 0.3 CoO 3 (111) exhibits the highest catalytic activity. Our findings provide a new avenue to prepare high-energy facet perovskite catalysts and we also clearly reveal the relationship between surface electronic structure and intrinsic CO oxidation activity of perovskite cobaltite.

Anionic redox chemistry is becoming increasingly important in explaining the intristic catalytic behavior in transition-metal oxides and improving catalytic activity. However, it is a great challenge to activate lattice oxygen in noble-metal-free perovskites for obtaining active peroxide species. Here, we take La 0.4 Sr 0.6 CoO 3-δ as a model catalyst and develop an anionic redox activity regulation method to activate lattice oxygen by tuning charge transfer between Co 4+ and O 2- . Advanced XAS and XPS demonstrate that our method can effectively decrease electron density of surface oxygen sites (O 2- ) to form more reactive oxygen species (O 2- x ), which reduces the activation energy barriers of molecular O 2 and leads to a very high CO catalytic activity. The revealing of the activation mechanism for surface oxygen sites in perovskites in this work opens up a new avenue to design efficient solid catalysts. Furthermore, we also establish a correlation between anionic redox chemistry and CO catalytic activity.

Cation segregation of perovskite oxide is crucial to develop high-performance catalysts. Herein, we achieved the exsolution of α-Fe 2 O 3 from parent La 0.85 FeO 3-δ by a simple heat treatment. Compared to α-Fe 2 O 3 and La 0.85 FeO 3-δ , α-Fe 2 O 3 -LaFeO 3- x achieved a significant improvement of lithium-oxygen battery performance in terms of discharge specific capacity and cycling stability. The promotion can be attributed to the interaction between α-Fe 2 O 3 and LaFeO 3- x . During the cycling test, α-Fe 2 O 3 -LaFeO 3- x can be stably cycled for 108 cycles at a limited discharge capacity of 500 mAh g -1 at a current density of 100 mA g -1 , which is remarkably longer than those of La 0.85 FeO 3-δ (51 cycles), α-Fe 2 O 3 (21 cycles), and mechanical mixing of LaFeO 3 and α-Fe 2 O 3 (26 cycles). In general, these results suggest a promising method to develop efficient lithium-oxygen battery catalysts via segregation.

In this work, a simple hydrothermal method was developed to synthesize CuO plates in centimeter scale for the first time. Plates of up to 20 μm thickness and several square millimeters in area have been prepared. The unusual size was obtained under ultrahigh-concentration NaOH and a planar chromium(III) oligomer, which served as a new kind of inorganic facet-directing agent. The obtained CuO plates were glossy black, free-standing, and crack-free. The chromium(III) oligomer offered ideal chemically active sites for adsorbing and confining Cu 2+ ions. They could be adsorbed on the surface of Cu(OH) 4 2- clusters via hydrogen-bonding interaction, which thus modified the growth orientation. The as-synthesized centimeter-scale CuO plates could possibly serve as substrates and electronic materials with potential applications.

A PdNi/RGO/polyoxometalate nanocomposite has been successfully synthesized by a simple wet-chemical method. Characterizations such as transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction analysis, and X-ray photoelectron spectroscopy are employed to verify the morphology, structure, and elemental composition of the as-prepared nanocomposite. Inspired by the fast-developing fuel cells, the electrochemical catalytic performance of the nanocomposite toward methanol and ethanol oxidation in alkaline media is further tested. Notably, the nanocomposite exhibits excellent catalytic activity and long-term stability toward alcohol electrooxidation compared with the PdNi/RGO and commercial Pd/C catalyst. Furthermore, the electrochemical results reveal that the prepared nanocomposite is attractive as a promising electrocatalyst for direct alcohol fuel cells, in which the phosphotungstic acid plays a crucial role in enhancing the electrocatalytic activities of the catalyst.