ChemInform Abstract: The Fluorite Related Modulated Structures of the Gd2(Zr2‐xCex)O7 Solid Solution: An Analogue for Pu Disposition.

The fluorite‐related structures of the Gd₂(Zr_2‐xCe_x)O₇ (0 ≤ x ≤ 2) solid solution, of interest as a model system for ceramic disposition of Pu (with Ce as a Pu surrogate), are determined by XRD, XANES, TEM, and EELS.     

Efficient Noble‐Metal‐Free Catalysts Supported by Three‐Dimensional Ordered Hierarchical Porous Carbon

Development of heterogeneous catalysts has attracted increasing attention, owing to their remarkable catalytic performance and recyclability. Herein, we report well‐developed heterogeneous catalysts with a three‐dimensional ordered hierarchical structure, constructed from nickel or cobalt nanoparticles embedded in porous carbon. The obtained catalysts were fully characterized by several techniques. On account of the uniform distribution of metal nanoparticles in the porous carbon matrix and large diffusion channels that allow for effective mass transport, the catalysts exhibited superior catalytic performance for styrene epoxidation reaction. In particular, the catalysts showed good catalytic activity, high selectivity and excellent recyclability toward the styrene epoxidation. Thus, this facile approach developed allows for fabricating advanced heterogeneous catalysts with high catalytic activities for useful practical applications.     

Nitrogen,Phosphorus, and Sulfur Co‐Doped Hollow Carbon Shell as Superior Metal‐Free Catalyst for Selective Oxidation of Aromatic Alkanes

Metal‐free heteroatom‐doped carbocatalysts with a high surface area are desirable for catalytic reactions. In this study, we found an efficient strategy to prepare nitrogen, phosphorus, and sulfur co‐doped hollow carbon shells (denote as NPS‐HCS) with a surface area of 1020 m² g^?1. Using a poly(cyclotriphosphazene‐co‐4,4′‐sulfonyldiphenol) (PZS) shell as carbon source and N, P, S‐doping source, and the ZIF‐67 core as structural template as well as extra N‐doping source, NPS‐HCS were obtained with a high surface area and superhydrophilicity. All these features render the prepared NPS‐HCS a superior metal‐free carbocatalyst for the selective oxidation of aromatic alkanes in aqueous solution. This study provides a reliable and facile route to prepare doped carbocatalysts with enhanced catalytic properties.     

A Noble‐Metal‐Free Nickel(II) Polypyridyl Catalyst for Visible‐Light‐Driven Hydrogen Production from Water

The complex [Ni(bpy)₃]²⁺ (bpy=2,2′‐bipyridine) is an active catalyst for visible‐light‐driven H₂ production from water when employed with [Ir(dfppy)₂(Hdcbpy)] [dfppy=2‐(3,4‐difluorophenyl)pyridine, Hdcbpy=4‐carboxy‐2,2′‐bipyridine‐4′‐carboxylate] as the photosensitizer and triethanolamine as the sacrificial electron donor. The highest turnover number of 520 with respect to the nickel(II) catalyst is obtained in a 8:2 acetonitrile/water solution at pH 9. The H₂‐evolution system is more stable after the addition of an extra free bpy ligand, owing to faster catalyst regeneration. The photocatalytic results demonstrate that the nickel(II) polypyridyl catalyst can act as a more effective catalyst than the commonly utilized [Co(bpy)₃]²⁺. This study may offer a new paradigm for constructing simple and noble‐metal‐free catalysts for photocatalytic hydrogen production.