Photoluminescence and electroluminescence of cationic PtAu2 heterotrinuclear complexes with aromatic acetylides.

Cationic PtAu2 heterotrinuclear complexes [PtAu2(dpmp)2(C[triple bond, length as m-dash]CR)2]2+ (dpmp = bis(diphenylphosphinomethyl)phenylphosphine, R = aryl) of aromatic acetylides were prepared. The PtAu2 structures are supported through doubly bridging dpmp and stabilized by a significant Pt-Au interaction. They are highly phosphorescent in fluid CH2Cl2 solution (Φem = 23.5%-78.9%), the solid state (Φem = 15.4%-70.2%), the PMMA film (Φem = 39.9%-71.7%) and the doping film of 61% TCTA : 31% OXD-7 : 8% PtAu2 complex (Φem = 16.9%-67.9%). The phosphorescence arises mainly from 3[π (C[triple bond, length as m-dash]CR) → π* (dpmp)] 3LLCT and 3[π (C[triple bond, length as m-dash]CR) → s/p (PtAu2)] 3LMCT triplet excited states for carbazole-acetylide complexes, whereas other complexes display a 3LLCT character mixed with noticeable PtAu2 centered 3[d → s/p] parentage. Utilizing a mixed host composed of hole-transporting TCTA and electron-transporting OXD-7 doped with 8% PtAu2 species as a light-emitting layer and CuSCN as a hole-transporting layer through an orthogonal solution process, the devices exhibit highly efficient electrophosphorescence with the highest current efficiency (CEmax) of 51.7 cd A-1 and external quantum efficiency (EQEmax) of 14.5%. The efficiency roll-off is small in the practical brightness range of 500-5000 cd m-2. The PtAu2 complexes with carbazole-acetylides display a higher electroluminescence efficiency ascribed to their better hole-transporting character as well as more facile energy transfer from mixed host materials.

A new cadmium-doped titanium-oxo cluster with stable photocatalytic H2 evolution properties.

A new Cd-doped titanium-oxo cluster (TOC) stabilized by tert-butylacetic acid ligands has been prepared through an easily handled solvothermal reaction; photocatalytic studies indicate that it displays good H2 evolution ability (3.15 µmol h(-1)), and moreover preserves high catalytic stability.

Phosphorescent PtAu2 Complexes with Differently Positioned Carbazole-Acetylide Ligands for Solution-Processed Organic Light-Emitting Diodes with External Quantum Efficiencies of over 20.

The utilization of phosphorescent metal cluster complexes as new types of emitting materials in organic light-emitting diodes (OLEDs) is becoming an alternative and viable approach for achieving high-efficiency electroluminescence. We report herein the design of cationic PtAu2 cluster complexes with differently positioned 9-phenylcarbazole-acetylides to serve as phosphorescent emitters in OLEDs. The rigid structures of PtAu2 complexes cause intense phosphorescence with quantum yields of over 85%, which originates from (3)[π(phenylcarbazole-acetylide) → π*(dpmp)] ligand-to-ligand and (3)[π(phenylcarbazole-acetylide) → p/s(PtAu2)] ligand-to-metal charge-transfer triplet excited states. When 8 wt % PtAu2 is doped to blended host materials of TCTA and OXD-7 (2:1 weight ratio) as light-emitting layers, solution-processed OLEDs give a current efficiency of 78.2 cd A(-1) and an external quantum efficiency (EQE) of 21.5% at a practical luminance of 1029 cd m(-2) with a slow efficiency roll-off upon increasing luminance. This represents the best device performance and the highest efficiency recorded at practical luminance for solution-processed OLEDs.

Construction of a supported Ru complex on bifunctional MOF-253 for photocatalytic CO2 reduction under visible light.

A MOF-253 supported active Ru carbonyl complex (MOF-253-Ru(CO)2Cl2) was constructed for photocatalytic CO2 reduction under visible light irradiation. Its performance can be further improved by immobilization as a photosensitizer. This study highlights the great potential of using MOFs as a solid ligand and platform for the assembly of a complicated catalytic system.