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Electrocatalytic hydrogenation (ECH) is a burgeoning strategy for the sustainable utilization of hydrogen. However, how to effectively suppress the competitive hydrogen evolution reaction (HER) is a big challenge to ECH catalysis. In this study, amine (NH2R)‐coordinated Pd nanoparticles loaded on carbon felt (Pd@CF) as a catalyst is successfully synthesized by a one‐step solvothermal reduction method using oleylamine as the reducing agent. An exceptional ECH reactivity on benzaldehyde is achieved on the optimal Pd@CF catalyst in terms of a high conversion (89.7%) and selectivity toward benzyl alcohol (89.8%) at −0.4 V in 60 min. Notably, the Faradaic efficiency for producing benzyl alcohol is up to 90.2%, much higher than that catalyzed by Pd@CF‐without N‐group (41.1%) and thecommercial Pd/C (20.9%). The excellent ECH performance of Pd@CF can be attributed to the enriched electrons on Pd surface resulted from the introduction of NH2R groups, which strengthens both the adsorption of benzaldehyde and the adsorbed hydrogen (Hads) on Pd, preventing the combination of Hads to form H2, that is, inhibiting the HER. This study gives a new insight into design principles of highly efficient electrocatalysts for the hydrogenation of unsaturated aldehydes molecules. [ABSTRACT FROM AUTHOR]

The interplay between magnetism and the topological band in metamagnetic materials has attracted researchers' attentions because these materials exhibit novel phenomena, such as the anomalous Hall effect (AHE) and quantum AHE. Here, the magnetotransport of DyPtBi single crystals in out‐of‐plane and in‐of‐plane magnetic field configurations is investigated. The results show a large unconventional anomalous Hall signal in the canted Type II antiferromagnetic state, indicating the existence of significant Berry curvature. This signal evolves into a large hump with DyPtBi entering the paramagnetic state and persists up to temperatures that are much higher than TN. Out‐of‐plane and in‐of‐plane measurements indicate that a larger unconventional Hall signal is observed at certain θ and ϕ angles. A giant planar anomalous Hall angle (AHA) of up to 30% is achieved in DyPtBi, which is comparable to that in a typical ferromagnetic Weyl semimetal. The results show that DyPtBi is a good platform for investigating the unconventional AHE and other novel physical properties in various potentially topologically nontrivial phases due to the interplay between canted antiferromagnetic structures and topology. [ABSTRACT FROM AUTHOR]

Novel composites of iron oxide encapsulated in macroporous silica with excellent arsenic adsorption performance have been successfully developed. Macroporous silica foams with large pore sizes of ≈100 nm and a high pore volume of 1.6 cm3 g−1 are chosen as the porous matrix. Electron tomography technique confirms that γ-Fe2O3 nanoparticles with an average particle size of ≈6 nm are spatially well-dispersed and anchored on the pore walls at even a high γ-Fe2O3 content of 34.8 wt%, rather than forming aggregates inside the pores or on the external surface. The open large-pore structure, high loading amount, and the non-aggregated nature of γ-Fe2O3 nanoparticles lead to increased adsorption sites and thus high adsorption capacities of both As (V) and As (III) without pre-treatment (248 and 320 mg g−1, respectively). Moreover, the composites can reduce the concentration of both As (V) and As (III) from 100 to 2 μg L−1. It is also demonstrated that the composites can be applied in a household drinking water treatment device, which can continuously treat 20 L of wastewater containing As (V) with the effluent concentration lower than the World Health Organization standard. [ABSTRACT FROM AUTHOR]

Development of multifunctional nanoscale coordination polymers (NCPs) allowing for T1- and T2-weighted targeted magnetic resonance (MR) imaging of tumors could significantly improve the diagnosis accuracy. In this study, nanoscale coordination polymers (NCPs) with a diameter of ≈80 nm are obtained with 1,1′-dicarboxyl ferrocene (Fc) as building blocks and magnetic gadolinium(III) ions as metallic nodes using a nanoprecipitation method, then further aminated through silanization. The amine-functionalized Fc-Gd@SiO2 NCPs enable the covalent conjugation of a fluorescent rhodamine dye (RBITC) and an arginine-glycine-aspartic acid (RGD) peptide as a targeting ligand onto their surface. The formed water-dispersible Fc-Gd@SiO2(RBITC)-RGD NCPs exhibit a low cytotoxicity, as confirmed by MTT assay. They have a longitudinal relaxivity ( r1) of 5.1 mM−1 s−1 and transversal relaxivity ( r2) of 21.7 mM−1 s−1, suggesting their possible use as both T1-positive and T2-negative contrast agents. In vivo MR imaging experiments show that the signal of tumor over-expressing high affinity αvβ3 integrin from T1-weighted MR imaging is positively enhanced 47±5%, and negatively decreased 33±5% from T2-weighted MR imaging after intravenous injection of Fc-Gd@SiO2(RBITC)-RGD NCPs. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2) is a promising high‐capacity anode for lithium‐ion batteries. However, the conversion reaction mechanism of MoS2 (the delithiation pathway in particular) has been controversial, which limits the rational optimization of its electrochemical performance. The main challenge is how to precisely identify the amorphous nanomaterials generated during lithiation/delithiation. Here, the structural evolutions of MoS2 during lithiation/delithiation are systematically investigated using synchrotron X‐ray absorption spectroscopy at Mo K‐edge and S K‐edge and Raman spectroscopy. It is revealed that amorphous MoS2 nanograins rather than sulfur as previously suggested, are formed after delithiation, and that the fully lithiated MoS2 electrode contains additional Mo‐S related phases besides the known Mo and Li2S. Density functional theory simulations suggest that the Mo nanoparticles formed during lithiation are very reactive with Li2S, thus enabling the regeneration of MoS2 upon delithiation. These findings deepen the understanding of the lithiation/delithiation mechanism of MoS2, which will pave the way for the rational design of advanced MoS2‐based electrodes. [ABSTRACT FROM AUTHOR]