Electric-Field Control of the Local Thermal Conductivity in Charge Transfer Oxides.

Phonons, the collective excitations responsible for heat transport in crystalline insulating solids, lack electric charge or magnetic moment, which complicates their active control via external fields. This presents a significant challenge in designing thermal equivalents of basic electronic circuit elements, such as transistors or diodes. Achieving these goals requires precise and reversible modification of thermal conductivity in materials.

Stability and Reversible Oxidation of Sub-Nanometric Cu Metal Clusters: Integrated Experimental Study and Theoretical Modeling.

Sub-nanometer metal clusters have special physical and chemical properties, significantly different from those of nanoparticles. However, there is a major concern about their thermal stability and susceptibility to oxidation. In situ X-ray Absorption spectroscopy and Near Ambient Pressure X-ray Photoelectron spectroscopy results reveal that supported Cu clusters are resistant to irreversible oxidation at least up to 773 K, even in the presence of 0.

Synthesis of photocatalytic cysteine-capped Cu clusters using Cu clusters as catalysts.

We report an easily scalable synthesis method for the preparation of cysteine-capped Cu clusters through the reduction of Cu(II) ions with NaBH, using Cu clusters as catalysts. The presence of such catalytic clusters allows controlling the formation of the larger Cu clusters and prevents the production of copper oxides or Cu(I)-cysteine complexes, which are formed when Cu is absent or at lower concentrations, respectively. These results indicate that small catalytic clusters could be involved, as precursor species before the reduction step, in the different methods developed for the synthesis of clusters.