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Efficient molecular oxygen activation is crucial for catalytic oxidation reaction, but highly depends on the construction of active sites. In this study, we demonstrate that dual adjacent Fe atoms anchored on MnO 2 can assemble into a diatomic site, also called as MnO 2 -hosted Fe dimer, which activates molecular oxygen to form an active intermediate species Fe(O = O)Fe for highly efficient CO oxidation. These adjacent single-atom Fe sites exhibit a stronger O 2 activation performance than the conventional surface oxygen vacancy activation sites. This work sheds light on molecular oxygen activation mechanisms of transition metal oxides and provides an efficient pathway to activate molecular oxygen by constructing new active sites through single atom technology. Efficient oxygen activation is crucial for catalytic oxidation reaction, but highly depends on the construction of active sites. Here, dual adjacent Fe atoms anchored on MnO 2 can assemble into a diatomic site, which activates molecular oxygen to form an active intermediate species Fe(O = O)Fe for CO oxidation.

Precisely managing electron transfer pathways throughout the catalytic reaction is paramount for bolstering both the efficacy and endurance of catalysts, offering a pivotal solution to addressing concerns surrounding host structure destabilization and cycling life degradation. This paper describes the integration of B-Ni dual single-atoms within MnO 2 channels to serve as an electronic reservoir to direct the electron transfer route during methane catalytic combustion. Comprehensive analysis discovers that B atoms weaken the interaction between O and Mn atoms by forming bonds with lattice oxygen atoms. Meanwhile, Ni atoms facilitate electron transfer to achieve the heightened activity of MnO 2 . The B-Ni dual-sites instead of Mn (IV) could accommodate excess electrons generated during the reaction to inhibit the formation of high spin Mn (III) species, thereby hindering the Jahn-Teller distortion and maintaining the catalyst stability. This work demonstrates an effective modification strategy to substantially prolong the service life of MnO 2 -based materials. Manganese oxides typically undergo irreversible phase transformations during redox reactions due to the Jahn-Teller effect. This study introduces adjacent B-Ni single-atomic sites as an electron reservoir to precisely control electron transfer pathways, enabling both high catalytic activity and stability.

A series of Ag.sub.3PO.sub.4/Bi.sub.2MoO.sub.6 p-n heterojunctions were assembled via the thin Bi.sub.2MoO.sub.6 nanosheets attached to the surface of rhombic dodecahedral Ag.sub.3PO.sub.4. The self-optimized Ag.sup.+/Ag.sup.0 pairs existed in the as-prepared heterojunction which are regarded as charge transmission bridge to accelerate the reaction. The samples presented much higher photocatalytic activity for the degradation of the target pollutions (completely degradation under solar light illuminating of 70 min for rhodamine B, 80 min for aureomycin and 70 min for tetracycline). It was found during the recycle test, photocatalytic performance of Ag.sub.3PO.sub.4/Bi.sub.2MoO.sub.6 underwent a successive increase since the second cycle in which the completely degradation of RhB was achieved after only 60 min visible light irradiation, confirming the composite is reusable with well stability. The oxidative mechanism was carefully investigation based on the scavengers trapping test, ESR spectra, XPS spectrum, photocurrent responses, and electrochemical impedance spectroscopy analysis. It proved Ag.sup.0 gradually generated from the as-prepared composite under solar light illuminating is fixed at an optimized content. The charge transfer was consequentially enhanced during the suitable level turning of Ag.sup.+/Ag.sup.0 pairs. Mediated by Ag.sup.0 sandwiched in p-n junction, the active species of the present photooxidative reaction experienced various period from .sup.·OH and h.sup.+ in the initial reaction to the additional .sup.·O.sub.2.sup.- in the successive recycle experiment owing to generation of the rectifying contact and Schottky junction. This study provides a new cognition for the improved reusability of the photocorrosion materials via the mutual transformation of metal monomers and ions.

A series of Ag 3 PO 4 /Bi 2 MoO 6 p–n heterojunctions were assembled via the thin Bi 2 MoO 6 nanosheets attached to the surface of rhombic dodecahedral Ag 3 PO 4 . The self-optimized Ag + /Ag 0 pairs existed in the as-prepared heterojunction which are regarded as charge transmission bridge to accelerate the reaction. The samples presented much higher photocatalytic activity for the degradation of the target pollutions (completely degradation under solar light illuminating of 70 min for rhodamine B, 80 min for aureomycin and 70 min for tetracycline). It was found during the recycle test, photocatalytic performance of Ag 3 PO 4 /Bi 2 MoO 6 underwent a successive increase since the second cycle in which the completely degradation of RhB was achieved after only 60 min visible light irradiation, confirming the composite is reusable with well stability. The oxidative mechanism was carefully investigation based on the scavengers trapping test, ESR spectra, XPS spectrum, photocurrent responses, and electrochemical impedance spectroscopy analysis. It proved Ag 0 gradually generated from the as-prepared composite under solar light illuminating is fixed at an optimized content. The charge transfer was consequentially enhanced during the suitable level turning of Ag + /Ag 0 pairs. Mediated by Ag 0 sandwiched in p–n junction, the active species of the present photooxidative reaction experienced various period from · OH and h + in the initial reaction to the additional · O 2 − in the successive recycle experiment owing to generation of the rectifying contact and Schottky junction. This study provides a new cognition for the improved reusability of the photocorrosion materials via the mutual transformation of metal monomers and ions.

In this investigation, phosphotungstic acid (H3PW12O40) was successfully self-assembly implanted into the interspace of K4Nb6O17 nanosheet via an impregnation method to form an adsorption-photocatalytic composite, in which n-type semiconductor K4Nb6O17 was selected as photo-electron emitter and H3PW12O40 was particularly used as an electronic transmitter. By characterizing with X-ray diffraction (XRD), transmission (TEM), scan electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and FT-IR spectrum (FT-IR), it confirmed that H3PW12O40 (HPW) was converted to the insoluble tiny particles of K3PW12O40 (KPW) with the remained primary Keggin group via an ion-exchanged H+ of HPW with K+ in K4Nb6O17 in the implanted process and was firmly bound to the surface of K4Nb6O17 to form well sandwich structure. UV-vis diffuse reflectance spectroscopy revealed that the band gap of K4Nb6O17-K3PW12O40 have a slight red shift compared with the single K4Nb6O17. Its adsorption-photocatalytic properties were evaluated with the removal of tetracycline as model reaction. Compared with pure K4Nb6O17, tetracycline removal rate can be significantly improved for the as-prepared sandwich. Importantly, the removal could still maintain 70% after five reuses in recycle tests at an acidic solution, inferring a good stability which was mainly ascribed to the formation of water-insoluble K3PW12O40. The separation and transfer process of photogenerated electrons were investigated by surface photovoltage spectroscopy (SPV). It proposed that the KPW anchored firmly on the interlayers of K4Nb6O17 through a O-K-O bridge plays a significantly role in promoting the separation of the photogenerated carriers and preventing the leakage and agglomeration of HPW. The present results showed that the strategy of the phosphotungstic acid binding in situ to K4Nb6O17 was favorable to promote the hetero-photocatalytic efficiency as well as reusability.

AbstractDeposition around the microvias opening is crucial for desirable quality of metallic micro components and micro bumps in electroforming. This paper presents a numerical and experimental study of shape evolution of electrodeposition front on the extent of over-plating. Computational models based on kinetics of the electrode reaction are used to simulate the entire deposition process from start of deposition until the formation of bumps. The effects of the current density and microstructure geometries are discussed through analyzing the current density distribution along the transient cathode surface. When the current density is 4 A dm−2, the significant Ni craters are observed for microvias with diameters of 200 µm in the over-plating stage. The dent depths decrease as the current density and diameter decrease. For the 30 µm diameters, spherical structures in the over-plating stage form upon the photolithographic patterns for an applied current density of 1 A dm−2. Furthermore, the spherical surfaces enable the fabrication of hemispherical lenses with various curvature radii.Graphical Abstract Spherical structures are obtained by electrodeposition into microcavities. A numerical and experimental study is carried out to study the mechanics of shape evolution. The polymeric microlenses are replicated through a combination of PDMS molding and UV curing. This process demonstrates the potential of this method in the fabrication of microlenses.

Precisely managing electron transfer pathways throughout the catalytic reaction is paramount for bolstering both the efficacy and endurance of catalysts, offering a pivotal solution to addressing concerns surrounding host structure destabilization and cycling life degradation. This paper describes the integration of B-Ni dual single-atoms within MnO channels to serve as an electronic reservoir to direct the electron transfer route during methane catalytic combustion. Comprehensive analysis discovers that B atoms weaken the interaction between O and Mn atoms by forming bonds with lattice oxygen atoms. Meanwhile, Ni atoms facilitate electron transfer to achieve the heightened activity of MnO . The B-Ni dual-sites instead of Mn (IV) could accommodate excess electrons generated during the reaction to inhibit the formation of high spin Mn (III) species, thereby hindering the Jahn-Teller distortion and maintaining the catalyst stability. This work demonstrates an effective modification strategy to substantially prolong the service life of MnO -based materials.

The overuse of antibiotics has led to an increase in bacterial resistance and, in turn, to a decreasing efficiency of the rare available antibiotics. Alternatively, gold nanoparticles are promising antibacterials due to their high specific surface area, easy modification by functional groups and broad-spectrum antibacterial activity. Their antibacterial properties are closely related to particle size, dispersibility and surface modification, which can be tuned by adjusting reaction conditions. Here, we review the synthesis and antibacterial performance of gold nanoparticles in the raw form or modified with metal, organic compounds and carbon. We present the effect of reaction conditions on particle dispersibility and size. We compare the various synthesis methods. Antibacterial activities and their mechanisms are discussed.

One long-standing issue in the paleoclimate records is whether East Asian Summer Monsoon peaked in the early Holocene or mid-Holocene. Here, combining a set of transient earth system model simulations with proxy records, we propose that, over northern China, monsoon rainfall peaked in the early Holocene, while soil moisture and tree cover peaked in the mid-Holocene. The delayed ecosystem (soil moisture and tree cover) response to rainfall is caused by the vegetation response to winter warming and the subsequent feedback with soil moisture. Our study provides a mechanism for reconciling different evolution behaviors of monsoon proxy records; it sheds light on the driving mechanism of the monsoon evolution and monsoon-ecosystem feedback over northern China, with implications to climate changes in other high climate sensitivity regions over the globe. How the East Asian Summer Monsoon has changed over the Holocene has been debated, as some proxy records disagree with each other. Here, the authors suggest that monsoonal rainfall peaked in the early Holocene, while ecosystem responses peaked in the mid-Holocene, explaining the differences between records.

Prostate cancer (PCa) is one of the most common malignancy in men. However, the molecular mechanism of its pathogenesis has not yet been elucidated. In this study, we demonstrated that CYLD, a novel deubiquitinating enzyme, impeded PCa development and progression via tumor suppression. First, we found that CYLD was downregulated in PCa tissues, and its expression was inversely correlated with pathological grade and clinical stage. Moreover, we discovered that CYLD inhibited tumor cell proliferation and enhanced the sensitivity to cell ferroptosis in PCa in vitro and in vivo, respectively. Mechanistically, we demonstrated that CYLD suppressed the ubiquitination of YAP protein, then promoted ACSL4 and TFRC mRNA transcription. Then, we demonstrated that CYLD could enhance the sensitivity of PCa xenografts to ferroptosis in vivo. Furthermore, we discovered for the first time that there was a positive correlation between CYLD expression and ACSL4 or TFRC expression in human PCa specimens. The results of this study suggested that CYLD acted as a tumor suppressor gene in PCa and promoted cell ferroptosis through Hippo/YAP signaling.