Silver has been recognized as a nontoxic, safe inorganic antibacterial/antifungal agent used for centuries. Silver demonstrates a very high potential in a wide range of biological applications, more particularly in the form of nanoparticles. Environmentally friendly synthesis methods are becoming more and more popular in chemistry and chemical technologies and the need for ecological methods of synthesis is increasing; the aim is to reduce polluting reaction by-products. Another important advantage of green synthesis methods lies in its cost-effectiveness and in the abundance of raw materials. During the last five years, many efforts were put into developing new greener and cheaper methods for the synthesis of nanoparticles. The cost decrease and less harmful synthesis methods have been the motivation in comparison to other synthesis techniques where harmful reductive organic species produce hazardous by-products. This environment-friendly aspect has now become a major social issue and is instrumental in combatting environmental pollution through reduction or elimination of hazardous materials. This review describes a brief overview of the research on green synthesis of silver metal nanoparticles and the influence of the method on their size and morphology.

A new atomic layer deposition (ALD) process was applied for the homogeneous coating of carbon nanotubes with vanadium oxide. It permits the coating of the inner and outer surface with a highly conformal film of controllable thickness and, hence, the production of high surface area hybrid materials at a so far unprecedented quality. The ALD-coated tubes are used as active component in gas-sensing devices. They show electric responses that are directly related to the peculiar structure, i.e., the p-n heterojunction formed between the support and the film.

Thin films of calcium substituted lanthanum manganite (La 12x Ca x MnO 3 ) have been synthesised by the ALD (atomic layer deposition) technique using Mn(thd) 3 (Hthd = 2,2,6,, La(thd) 3 , Ca(thd) 2 , and ozone as precursors. The effect of each of these precursors on the product stoichiometry has been investigated, and ALD type growth was achieved in the temperature range 200-330 uC. A concept on precursor surface area coverage has been applied in order to describe the difference between pulsed and obtained cation stoichiometry. The La 12x Ca x MnO 3 films are low in carbonate impurities although Ca(thd) 2 and ozone alone as precursors would give CaCO 3 . Mn(thd) 3 can be used as a precursor for ALD growth of these oxides for temperatures up to 330 uC when codeposited along with Ca and La, whereas 240 uC is the upper usable temperature for Mn(thd) 3 when Mn is deposited alone. Films have been deposited on substrates of (amorphous) soda-lime glass and single crystals of Si(100), MgO(100), SrTiO 3 (100), and LaAlO 3 (100). Growth with a cube-on-cube epitaxy has been achieved for SrTiO 3 (100) and LaAlO 3 (100) substrates. Magnetoresistive properties are recorded for films with a composition close to La 0.