Citrate Reduction in the Presence of PVP

As mentioned briefly in Section 7.3.2, a spin-off application of the diol reduction has been the citrate or DMF reductions in the presence of PVP at an elevated temperature [31, 68, 70], When citrate ion in aqueous solution is used in the reduction of gold precursors, a mass production of triangular nanoplates was realized. It was also shown that the nanoplate could be further fabricated, by using fast ion bombardment (FIB), into a future component of a possible nanomachine, such as a nanometer-sized gear element [31]. As more PVP was added the width and thickness of the nanoplates increased monotonically this contrasted with the polyol process, where smaller crystals were formed as the molar ratio of PVP increased 

Figu re 7.9 (a-d) Field effect SEM images of gold nanoplates obtained under the thermal reduction employing citrate ions and PVP in aqueous solution. Average width and thickness of the acquired nanoplates was (a) 450 nm and 39 nm (b) 310nm and 28 nm  

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