Synthese und Kristallstruktur von iso‐Butylimidogalliummethyl, [CH3Ga–NCH2CH(CH3)2]6

Synthesis and X‐Ray Structure Determination of iso ‐Butylimido Galliummethyl, [CH₃Ga–NCH₂CH(CH₃)₂]₆ The thermal decomposition of [Me₂Ga–N(ⁱBu)SnMe₃]₂ (prepared by the reaction of [Me₂SnNⁱBu]₃ with GaMe₃ in a 1:3 molar ratio) in an evacuated, sealed tube at 160°C forms [MeGaNⁱBu]₆ in high yield and SnMe₄. Mass, ¹H and ¹³C NMR as well as some IR and Raman spectroscopic data are given and the crystal structure of this cage molecule with a hexagonal prismatic Ga₆N₆ skeleton has been determined.     

η5-Phospholylgallium: The First Monomeric Polyhapto Compound between a Phospholyl Ligand and a Main Group Metal

Monomeric polyhapto-bound phospholyl compounds were hitherto unknown for the main group elements. Use of a solution of metastable GaBr has allowed the synthesis of monomeric η⁵-phospholylgallium, which has been characterized by X-ray structure analysis as the Cr(CO)₅ complex 1 .     

Enantioselective Ring Opening of Epoxides with 4-Methoxyphenol Catalyzed by Gallium Heterobimetallic Complexes: An Efficient Method for the Synthesis of Optically Active 1,2-Diol Monoethers

Useful chiral building blocks such as 1,2-diols can be obtained by the enantioselective ring opening of achiral epoxides with oxygen nucleophiles. The ring opening is carried out effectively (up to 94 % ee) with 4-methoxyphenol and catalytic amounts of gallium complexes. The novel complex GaSO 1 displays a particularly high catalytic activity.     

Mononuclear gallium(III) complexes based on salicylaldoximes: Synthesis,structure and spectroscopic characterization

The reactions of Ga(acac)₃ with salicylaldoxime (saoH₂) and methyl-salicylaldoxime (Me-saoH₂) in dichloromethane/hexane afforded the complexes [Ga(acac)(saoH)₂] (1) and [Ga(acac)₃][Ga(acac)(MesaoH)₂] (2), respectively, in high yields. The crystal structures of 1 and 2 have been determined by single-crystal X-ray crystallography. Both complexes are mononuclear with the Ga(III) atoms being in octahedral environments surrounded by two bidentate chelate R-saoH⁻ and one bidentate chelate acac⁻ ligands. A [Ga(acac)₃] moiety has co-crystallized along with the methylsalicylaldoximato complex. Characteristic IR as well as NMR data are discussed in terms of the nature of bonding in the structures of the two complexes. ¹H and ¹³C NMR data in CDCl₃ indicate that the salicylaldoximato complexes isomerize in solution.     

氮化镓发光二级管蓝光转换材料的合成和发光性质

合成了Ce3＋掺杂的稀土石榴石结构复合氧化物体系(Y1-xGdx)3Al5O12、(Y1-xLux)3Al5O12、(Y1-xLax)3Al5O12、(Y1-xYbx)3Al5O12和(Y1-xTbx)3Al5O12.重点研究了(Y1-xGdx)3Al5O12:Ce3＋和(Y1-xLux)3Al5O12:Ce3＋两个体系的晶体结构和发光性质.这些体系都具有立方石榴石结构.(Y1-xGdx)3Al5O12:Ce3＋体系随Gd取代Y,晶胞参数略有增加.荧光光谱的发射波长随Gd浓度增加发生红移,当x=0.5时发射波长达到最大值（560 nm）,并不再随Gd含量增加而变化. (Y1-xLux)3Al5O12:Ce3＋的晶胞参数随 Lu取代Y而减小,但均保持了立方石榴石结构.荧光光谱的发射波长随Lu3＋的增加向短波方向移动,Lu3Al5O12:Ce3＋的发射波长的峰值为520 nm,体系的蓝移量是20 nm.利用分离发光中心的位形坐标模型对波长的移动作了定性解释.这两个体系的发射波长的可调节特性,对改善与氮化镓发光二极管(LED)匹配的蓝光转换材料的色坐标、色温等显色性质具有重要意义.     

Dynamic Activation of Ga Sites by Pt Dopant in Low-Temperature Liquid-Metal Catalysts

Liquid GaPt catalysts with Pt concentrations as low as 1×10⁻⁴ atomic % have recently been identified as highly active for the oxidation of methanol and pyrogallol under mild reaction conditions. However, almost nothing is known about how liquid state catalysts support these significant improvements in activity. Here, ab initio molecular dynamics simulations are employed to examine GaPt catalysts in isolation and interacting with adsorbates. We find that persistent geometric features can exist in the liquid state, given the correct environment. We postulate that the Pt dopant may not be limited to direct involvement in catalysis of reactions, but rather that its presence can also enable Ga atoms to become catalytically active.     

Beyond Reduction Cocatalysts: Critical Role of Metal Cocatalysts in Photocatalytic Oxidation of Methane with Water**

Environmentally sustainable and selective conversion of methane to valuable chemicals under ambient conditions is pivotal for the development of next-generation photocatalytic technology. However, due to the lack of microscopic knowledge about non-thermal methane conversion, controlling and modulating photocatalytic oxidation processes driven by photogenerated holes remain a challenge. Here, we report novel function of metal cocatalysts to accept photogenerated holes and dominate selectivity of methane oxidation, which is clearly beyond the conventional concept in photocatalysis that the metal cocatalysts loaded on the surfaces of semiconductor photocatalysts mostly capture photogenerated electrons and dominate reduction reactions exclusively. The novel photocatalytic role of metal cocatalysts was verified by operando molecular spectroscopy combined with real-time mass spectrometry for metal-loaded Ga₂O₃ model photocatalysts under methane and water vapor at ambient temperature and pressure. Our concept of metal cocatalysts that work as active sites for both photocatalytic oxidation and reduction provides a new understanding of photocatalysis and a solid basis for controlling non-thermal redox reactions by metal-cocatalyst engineering.     

Highly Efficient Decomposition of Perfluorocarbons for over 1000 Hours via Active Site Regeneration

Tetrafluoromethane (CF₄), the simplest perfluorocarbon (PFC), has the potential to exacerbate global warming. Catalytic hydrolysis is a viable method to degrade CF₄, but fluorine poisoning severely restricts both the catalytic performance and catalyst lifetime. In this study, Ga is introduced to effectively assists the defluorination of poisoned Al active sites, leading to highly efficient CF₄ decomposition at 600 °C with a catalytic lifetime exceeding 1,000 hours. ²⁷Al and ⁷¹Ga magic-angle spinning nuclear magnetic resonance spectroscopy (MAS NMR) showed that the introduced Ga exists as tetracoordinated Ga sites (Ga_IV), which readily dissociate water to form Ga−OH. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density function theory (DFT) calculations confirmed that Ga−OH assists the defluorination of poisoned Al active sites via a dehydration-like process. As a result, the Ga/Al₂O₃ catalyst achieved 100 % CF₄ decomposition keeping an ultra-long catalytic lifetime and outperforming reported results. This work proposes a new approach for efficient and long-term CF₄ decomposition by promoting the regeneration of active sites.