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Porous copper nanoarchitectures are obtained selectively by acid-dealloying of Mg–Cu precursors prepared by microwave-induced-metal-plasma methods; the entire process is reversible.

The thermal decomposition reactions of CH 3 CH 2 C(CH 3 ) 2 COOAg (1), (CH 3 ) 3 SiCH 2 COOAg (2), CF 3 COOAg (3), (CH 3 ) 3 CCOOAg (4), C 2 H 5 COOAg (5), C 3 F 7 COOAg (6), C 6 F 13 COOAg (7) and (CF 2 ) 3 (COOAg) 2 (8) were studied in N 2 atmosphere using thermogravimetry (TG), derivative thermogravimetry and differential thermal analysis. Characterized compounds decomposed in one-or multistep processes with metallic silver formation in the range 215-465°C. TG-IR studies of gases evolved during thermolysis revealed products of decomposition, such as carbox ylic acids, CO 2 and recombination reactions.

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Powders and thin films of copper nitride, Cu3N, can be synthesised simply from copper(ii) trifluoroacetate, the latter by facile solution processing, resulting in stoichiometric nanostructured semiconducting materials with a band gap of 1.48 eV.

Improvements in the thermoelectric performance of n-type Bi2Te3 materials to more closely match their p-type counterparts are critical to promote the continued development of bismuth telluride thermoelectric devices. Here the unconventional heteroatom dopant, niobium, has been employed as a donor in Bi2Te3. Nb substitutes for Bi in the rhombohedral Bi2Te3 structure and exhibits multiple roles in its modulation of electrical transport and defect-induced phonon scattering. The carrier concentration is significantly increased as electrons are afforded by aliovalent doping and formation of vacancies on the Te sites. In addition, incorporation of Nb in the pseudoternary Bi2–x Nb x Te3−δ system increases the effective mass, m*, which is consistent with cases of “conventional” elemental doping in Bi2Te3. Lastly, inclusion of Nb induces both point and extended defects (tellurium vacancies and dislocations, respectively), enhancing phonon scattering and reducing the thermal conductivity. As a result, an optimum zT of 0.94 was achieved in n-type Bi0.92Nb0.08Te3 at 505 K, which is dramatically higher than an equivalent undoped Bi2Te3 sample. This study suggests not only that is Nb an exciting and novel electron dopant for the Bi2Te3 system but also that unconventional dopants might be utilized with similar effects in other chalcogenide thermoelectrics.

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3-D nanocomposites of (reduced) graphene oxide and ammonia borane can be fabricated in a one-step ice templating process from aqueous suspensions. The nanocomposites release hydrogen at a reduced onset temperature, suppressing the release of diborane, borazine and ammonia.