The controllable synthesis of phosphorus (P) doped noble metal electrocatalysts with a well‐defined structure and composition has attracted sufficient attention in energy chemistry. In this study, atomic‐level P‐doped Pt nanodendrites (PtP NDs) with tunable composition and highly branched architecture are successfully prepared by post‐phosphating reaction of sodium hypophosphite monohydrate at room temperature. Due to its electrophilic properties, P effectively regulates the electronic structure of the d‐orbitals of Pt. The charge change induced by P on a local scale can effectively regulate the selective adsorption of electrocatalytic reaction intermediates. The electrocatalytic results show that the η10 value of PtP NDs in hydrogen evolution reaction is only 13.3 mV, and the mass activity of PtP NDs in methanol oxidation reaction is 4.2 A mg−1, which is 3.8 times larger than that of commercial Pt/C. Most importantly, the atomic‐level P doping greatly improves the stability of PtP NDs, which is crucial to facilitating the catalysts’ commercialization process.

Highly branched ultrathin Pt–Ru nanodendrites with an average thickness of 1.8 nm were prepared and exhibited enhanced MOR performance.

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Curved ultrathin PtPd nanodendrites (CNDs) with long-range compressive strain and highly branched feature are first prepared by a functional surfactant-induced strategy. Precise synthesis realized the construction of both curved and flat PtPd nanodendrites (NDs) with the same atomic ratio, which contributed to exploration of the strain effect on electrocatalytic performance alone. Abundant evidence is provided to confirm that the long-range compressive strain in curved PtPd architectures can effectively tailor the local coordination environment of active sites, lower the position of the d-band center, weaken the adsorption energy of the intermediates (e.g., H* and CO*), and ultimately increase their intrinsic activity. The density functional theory (DFT) calculations further reveal that the introduction of compressive strain weakens the Gibbs free-energy of the intermediate (ΔG H* ), which is favorable for accelerating the hydrogen evolution reaction (HER) kinetics. A similar enhanced electrocatalytic performance can also be found in the methanol oxidation reaction (MOR).

The ionothermal synthesis of extra-large-pore aluminophosphate zeotype with -CLO topological structure, DNL-1, was studied by using 1,6-hexanediamine and several quaternary ammonium compounds with different types of cations and anions as co-structure-directing agents (co-SDAs). The phase selectivity and crystallization process were investigated, and results showed that the crystallization of the -CLO and LTA structures correlated with the alkalinity and concentration, rather than with the structure of the co-SDA. By combining solid/solution C NMR spectroscopy and other characterizations on DNL-1 obtained with different co-SDAs, it was demonstrated that the ionic-liquid cation was unalterably occluded in the structure, whereas occlusion of the co-SDA cation was not imperative. A plausible crystallization pathway was accordingly deduced, in which alkaline co-SDA, which acted as an acidity regulator in the ionothermal system, could facilitate the formation of the double-four-ring (d4r) unit (Al P O ), and influence their subsequent assembly mode around ionic-liquid cations, and thus, direct the crystallization of -CLO and LTA structures at different concentrations of co-SDA.

A novel Gd(iii) complex, Gd(TTA)-DPPZ, was designed and assembled as a dual-modal probe for the simultaneous fluorescence and magnetic resonance imaging (MRI) detection of fluoride ions in aqueous media and in vivo. In this system, the Gd(iii) center is not only serving as a MRI signal output unit, but also as a binding site for fluoride ions. When appropriate equivalents of fluoride ions were added into the solution of Gd(TTA)-DPPZ, the replacement of the coordination water led to a decrease of the longitudinal relaxivity (r) as well as distinct spectroscopic changes, by which MRI/fluorescence dual-modal fluoride ion sensing was achieved. In the presence of fluoride ions, a 2-fold fluorescence emission enhancement of Gd(TTA)-DPPZ, and a notable decrease of the UV-vis absorption spectrum were observed. The fluorescence detection limit for fluoride ions was established at 70 nM. Gd(TTA)-DPPZ also exhibits about 75% decrease of the longitudinal relaxivity (r) upon addition of fluoride ions in aqueous medium. The appropriate blood circulation time of Gd(TTA)-DPPZ allows its potential application in MRI in vivo. The results demonstrated that Gd(TTA)-DPPZ could serve as a potential MRI/fluorescence bimodal imaging agent for the specific and high-sensitive sensing of fluoride ions in vivo.

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