Uniform magnetite, hematite, and goethite nanocrystals were prepared through an attractive method based on an oleic acid/alcohol/water system. By adjusting the synthetic parameters (base concentration, alcohol content, categories of alcohols, etc.), the controlled synthesis of uniform magnetite, hematite, and goethite nanocrystals can be easily achieved. Detailed investigations on the effect of the experimental parameters on the morphology of the final products and the phase transitions among the magnetite, hematite, and goethite phases were carried out. Finally, a method of doping other metal ions into magnetite was developed and the magnetic properties of magnetite doped with different metal elements were studied.

Nanocages with controllable shapes, tunable compositions, and narrow size distributions have been synthesized by using the monodispersed ceria clusters as templates.

In this Full Paper, a water/alcohol/oleic acid system was developed to prepare NaYF4 nanocrystals with predictable size, shape and phase. The structural and kinetic factors that govern the phase and shape evolution of NaYF4 nanocrystals have been carefully studied, and the influence of NaF to Y3+ ratio, reaction time and temperature on the phase and shape evolution of the as‐prepared NaYF4 samples was systematically investigated and discussed. It was found that the NaF to Y3+ ratio was responsible for the shape evolution while temperature and reaction time was the key for the phase control of the NaYF4 nanocrystals. This study would be suggestive for the precisely controlled growth of inorganic nanocrystals, especially for those usually crystallizing in diverse crystal structures.

Well‐rounded: Water‐dispersed colloidal spheres that are self‐assembled from nanocrystals with different size, shape, composition, and surface ligand were prepared through a versatile emulsion‐based self‐assembly (EBS) approach. Through this emulsification process, a dispersion of BaCrO4 nanocrystals in cyclohexane (see picture, left) can be transformed into a dispersion of colloidal spheres of BaCrO4 (see picture, right).

Bimetallic phosphides have attracted research interest for their synergistic effect and superior electrocatalytic activities for electrocatalytic water splitting. Herein, a MOF-derived phosphorization approach was developed to produce NiP-CoP bimetallic phosphides as bifunctional electrocatalysts for both hydrogen and oxygen evolution reactions (HER and OER). NiP-CoP shows superior electrocatalytic activities to both pure NiP and CoP toward HER and OER, revealing a strong synergistic effect. High-resolution transmission electron microscopy and energy dispersive X-ray spectroscopy elemental mapping analysis show that, in the sample NiP-CoP, the NiP and CoP nanoparticles with an average particle size 10-20 nm were mixed closely on the nanoscale, creating numerous NiP/CoP interfaces. By comparison with the sample NiP+CoP, in which seldom NiP/CoP interfaces exist, we documented that the NiP/CoP interface is an essential prerequisite to realize the synergistic effect and to achieve the enhanced electrocatalytic activities in NiP-CoP bimetallic phosphides. This finding is meaningful for designing and developing bicomponent and even multicomponent electrocatalysts.