Pd2Ge nanoparticles were synthesized by superhydride reduction of K2PdCl4 and GeCl4. The syntheses were performed using a solvothermal method in the absence of surfactants, and the size of the nanoparticles was controlled by varying the reaction time. The powder X-ray diffraction (PXRD) and transmission electron microscopy data suggest that Pd2Ge nanoparticles were formed as an ordered intermetallic phase. In the crystal structure, Pd and Ge atoms occupy two different crystallographic positions with a vacancy in one of the Ge sites, which was proved by PXRD and energy-dispersive X-ray analysis. The catalyst is highly efficient for the electrochemical oxidation of ethanol and is stable up to the 250th cycle in alkaline medium. The electrochemical active surface area and current density values obtained, 1.41 cm2 and 4.1 mA cm–2, respectively, are superior to those of the commercial Pd on carbon. The experimentally observed data were interpreted in terms of the combined effect of adsorption energies of CH3CO and OH radical, d-band center model, and work function of the corresponding catalyst surfaces.

Facile synthesis of luminescent metal nanoclusters (NCs) accompanied by emission color tuning is currently an active area of research. In this work we describe a rapid (1 s) room temperature synthesis of luminescent Au NCs from completely nonluminescent NCs through the incorporation of Zn. The nanoclusters are initially stabilized by mercaptopropionate, and the coordination of Zn with the carboxylate groups of the ligands rigidifies the Au(i) thiolates restricting the intramolecular rotation-vibrational motion. This significantly reduces the nonradiative relaxation of the excited state to produce yellow luminescent NCs (λ = 580 nm, QY: 6%, τ = 0.2 ms) with almost a million-fold emission enhancement. The enhanced luminescence is due to the self-assembly mediated aggregation induced emission (AIE) of NCs. These NCs on aging for 24 hours transform to highly ordered green emitting NCs (λ = 500 nm, QY: 20%, τ = 20 ns). The blue shift in emission is due to the dominance of inter Au(i)-Au(i) interaction and inter-NC Zn interaction over the intra modes. TEM images show this distinct transition, a decrease in inter NC distance with increased self-assembly. Excited state relaxation dynamics associated with Au(i) thiolate shell dynamics in yellow and green emitting NCs is explained based on the time resolved fluorescence study. The rapid formation of luminescent NCs from nl-NCs has been used for efficient visual and fluorimetric detection of Zn.

Hybrid silica‐organic nanohelices are used to organize a large variety of nonchiral small organic molecules or inorganic anions to nanometer‐sized assemblies. Such chiral organization of achiral molecules induces chiroptical properties as detected by vibrational or electronic circular dichroism (CD), as well as from circularly polarized luminescence (CPL).

A luminescent hybrid gel was prepared by incorporating organic ligand capped CdSe quantum dots (QDs) into a steroid-dimer derived organogel. Photophysical measurements and electron microscopy studies allowed us to understand the nature of the hybrid. Detailed analysis of the excited state dynamics of the hybrid was carried out using a kinetic decay model. The luminescence of the QDs in the hybrid was unaltered by taking it through a gel-sol-gel cycle induced by thermal stimuli. We believe that the results obtained herein provide a route to develop a thermoresponsive device for practical applications, because of the spatial assembly between soft organic scaffolds and colloidal QDs.