In the absence of any usual protective agent, stable platinum, rhodium, and ruthenium metal nanoclusters with small particle size in organic media are effectively prepared by heating corresponding metal hydroxide colloids in ethylene glycol containing NaOH for the first time. The average diameters of the Pt, Rh, and Ru nanoclusters determined by means of transmission electron microscopy are in a range from 1 to 2 nm. The particle size distribution in each colloidal solution is sharp, within 2 nm wide. Studies on the preparation conditions and some properties of the “unprotected” Pt metal nanoclusters have been carried out. By adjusting pH, it is convenient to separate the Pt nanocluster as a precipitate from glycol solvent, and the precipitated Pt nanoclusters can easily be “dissolved” in many organic solvents to form transparent Pt nanocluster solutions with high concentration in the absence of usual protective agents. The “unprotected” Pt nanoclusters can also be easily transformed to various protected Pt nanoclusters with the same Pt cores and can be extracted into toluene by forming PPh3-modified Pt clusters.

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Carbon nanofibers, CNFs, due to their superior strength, conductivity, flexibility, and durability have great potential as a material resource but still have limited use due to the cost intensive complexities of their synthesis. Herein, we report the highyield and scalable electrolytic conversion of atmospheric CO 2 dissolved in molten carbonates into CNFs. It is demonstrated that the conversion of CO 2 → C CNF + O 2 can be driven by efficient solar, as well as conventional, energy at inexpensive steel or nickel electrodes. The structure is tuned by controlling the electrolysis conditions, such as the addition of trace transition metals to act as CNF nucleation sites, the addition of zinc as an initiator and the control of current density. A less expensive source of CNFs will facilitate its adoption as a societal resource, and using carbon dioxide as a reactant to generate a value added product such as CNFs provides impetus to consume this greenhouse gas to mitigate climate change.

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