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Background: In the central nervous system, type 2 vesicular monoamine transporters (VMAT2) are responsible for the reuptake of monoamines from synaptic junction back to pre-synaptic terminal vesicles. These transporters are functionally crucial as they reflect the integrity of monoamine neurons. D6-[18F]FP-(+)-DTBZ, a novel deuterated VMAT2 radioligand, has shown promise as a potential PET tracer for the diagnosis of Parkinson's disease (PD). This study evaluates the biodistribution and dosimetry of D6-[18F]FP-(+)-DTBZ and includes a head-to-head comparison with its non-deuterated version, [18F]FP-(+)-DTBZ (AV-133), in healthy individuals and PD patients. Results: The automated synthesis of D6-[18F]FP-(+)-DTBZ using the SPE method was accomplished in 35 min, yielding a high radiochemical purity (> 99%) and high radiochemical yields (35 ± 5%). The biodistribution and dosimetry study indicated an effective dose of 37.1 ± 7.2 μSv/MBq, with the liver receiving the highest radiation dose (289.6 ± 42.1 μGy/MBq), followed by pancreas (185.2 ± 29.1 μGy/MBq). Brain imaging with D6-[18F]FP-(+)-DTBZ exhibited a significantly increased uptake in VMAT2-rich regions, particularly the striatum. In a head-to-head comparison between [18F]FP-(+)-DTBZ and D6-[18F]FP-(+)-DTBZ, the latter exhibited approximately 15% higher SUVR in the caudate, putamen, and nucleus accumbens. Preliminary studies in PD patients showed a substantial reduction in VMAT2 uptake in the striatum, with the most pronounced decrease observed in the putamen (a 53% decline). Conclusions: D6-[18F]FP-(+)-DTBZ is a safe and improved VMAT2-specific imaging agent, which may be suitable for diagnosing PD by evaluating changes in VMAT2 binding of monoamine neurons in the brain. Trial registration Chinese Clinical Trial Registry, ChiCTR2200057218, Registered 16 August 2021, https://www.chictr.org.cn/bin/project/edit?pid=142725. [ABSTRACT FROM AUTHOR]

For the 2D metal‐free carbon catalysts, the atomic coplanar architecture enables a large number of pz orbitals to overlap laterally, thus forming π‐electron delocalization, and the delocalization degree of the central atom dominates the catalytic activity. Herein, designing sulfur‐doped defect‐rich graphitic carbon nitride (S‐Nv‐C3N4) materials as a model, we propose a strategy to promote localized electron polarization by enhancing the ferromagnetism of ultra‐thin 2D carbon nitride nanosheets. The introduction of sulfur (S) further promotes localized ferromagnetic coupling, thereby inducing long‐range ferromagnetic ordering and accelerating the electron interface transport. Meanwhile, the hybridization of sulfur atoms breaks the symmetry and integrity of the unit structure, promotes electron enrichment and stimulating electron delocalization at the active site. This optimization enhances the *OOH desorption, providing a favorable kinetic pathway for the production of hydrogen peroxide (H2O2). Consequently, S‐Nv‐C3N4 exhibits high selectivity (>95 %) and achieves a superb H2O2 production rate, approaching 4374.8 ppm during continuous electrolysis over 300 hour. According to theoretical calculation and in situ spectroscopy, the ortho‐S configuration can provide ferromagnetic perturbation in carbon active centers, leading to the electron delocalization, which optimizes the OOH* adsorption during the catalytic process. [ABSTRACT FROM AUTHOR]

Efficient oxygen evolution reaction electrocatalysts are essential for sustainable clean energy conversion. However, catalytic materials followed the conventional adsorbate evolution mechanism (AEM) with the inherent scaling relationship between key oxygen intermediates *OOH and *OH, or the lattice-oxygen-mediated mechanism (LOM) with the possible lattice oxygen migration and structural reconstruction, which are not favorable to the balance between high activity and stability. Herein, we propose an unconventional Co-Fe dual-site segmentally synergistic mechanism (DSSM) for single-domain ferromagnetic catalyst CoFeSx nanoclusters on carbon nanotubes (CNT) (CFS-ACs/CNT), which can effectively break the scaling relationship without sacrificing stability. Co3+ (L.S, t2g6eg0) supplies the strongest OH* adsorption energy, while Fe3+ (M.S, t2g4eg1) exposes strong O* adsorption. These dual-sites synergistically produce of Co-O-O-Fe intermediates, thereby accelerating the release of triplet-state oxygen (↑ O = O ↑). As predicted, the prepared CFS-ACs/CNT catalyst exhibits less overpotential than that of commercial IrO2, as well as approximately 633 h of stability without significant potential loss. Efficient oxygen evolution reaction electrocatalysts are essential for sustainable clean energy conversion. Here, the authors propose a Co-Fe dual-site to facilitate the ferromagnetic O-O bond coupling to achieve a great balance between activity and stability. [ABSTRACT FROM AUTHOR]

Water electrolysis is severely impeded by the kinetically sluggish oxygen evolution reaction (OER) due to its inherent multistep four-electron transfer mechanism. However, designing advanced OER electrocatalysts with abundant active sites, robust stability, and low cost remains a huge challenge. Herein, a facile and versatile multiscale manipulating strategy was proposed to construct a novel V-NiFe2O4@Ni2P heterostructure self-supported on Ni foam (V-NiFe2O4@Ni2P/NF). In such unique architecture, the intrinsic OER catalytic activity was greatly boosted by the in-situ generated heterogeneous Ni2P phase induced by precisely selective phosphorylation of the NiFe-precursor, while the synchronous metal V doping stimulated the activity via modulating the electronic configuration, thus synergistically promoting its OER kinetics. In addition, the binder-free catalyst built from three-dimensional (3D) nanosheet arrays (NSs) can offer a large active surface for efficient charge/mass transfer and a robust scaffold for the integrated structure. The as-prepared flexible electrode exhibited superior OER activity with an ultra-low overpotential of 230 mV at 50 mA·cm−2 and outstanding long-term stability for 40 h. This discovery is expected to provide an opportunity to explore efficient and stable commercial materials for scalable, efficient, and robust electrochemical hydrogen (H2) production. [ABSTRACT FROM AUTHOR]

Hydrogen production by electrocatalytic water splitting is a pollution-free, energy-saving, and efficient method. The low efficiency of hydrogen production, high overpotentials and expensive noble-metal catalysts have limited the development of hydrogen production from electrocatalytic water splitting. Therefore, the exploration of bifunctional electrocatalysts for water overall splitting to produce hydrogen is of profound significance. Herein, Ni3S2@Ni2P/MoS2 heterostructure electrocatalysts were synthesized on Ni foam through an environmentally friendly hydrothermal method and low-temperature phosphating method. The synergistic effects between different components and the mutual substitution principle between sulfur atoms and phosphorus atoms greatly improve the OER performance of the electrocatalyst. It is also an effective strategy to optimize the adsorption energies of intermediates by the design of heterostructured catalysts composed of multiple substances. Ni3S2@Ni2P/MoS2 only requires a low overpotential (η10) of 175 mV at a current density of 10 mA cm−2 in 1.0 M KOH solution and the stable duration exceeds 40 h. In addition, this heterogeneous structure is assembled into an electrolytic cell for overall water splitting, which exhibits a low cell voltage of 1.61 volts and retains the robust stability over 30 h at 10 mA cm−2. The Ni3S2@Ni2P/MoS2 heterostructure prepared in this research provides a strategy for exploring other heterostructured electrocatalysts with different components. [ABSTRACT FROM AUTHOR]

This study reports, for the first time, the second-harmonic generation (SHG) property of Pb7F12Cl2 as a promising infrared nonlinear optical (NLO) material. Powder second-harmonic generation (SHG) indicates that the compound exhibits phase-matchable SHG properties, which are 1.6 times stronger than those of KH2PO4 (KDP). The infrared transmission range could reach 20 μm. The UV absorption indicated that the band gap was about 4.5 eV. A preliminary measurement of laser damage threshold (LDT) is about 80 MW cm−2, which is much higher than AgGaS2 (currently commercialized IR NLO material, 5.2 MW cm−2, measured in the same condition), indicating that Pb7F12Cl2 is a potential IR NLO material with high LDT. Theoretical calculations were also performed to elucidate its band structure, electronic configuration and second-order nonlinear coefficients. Particularly, the distinct role of different Pb atoms located in divergent coordinations has also been elaborated using orbital analysis. [ABSTRACT FROM AUTHOR]