Silver Nanoplatelet Films: Electroless Plating, Funtionalization and Electrocatalytic Applications

Electroless plating has been developed primarily for the deposition of continuous, polycrystalline films; yet, the morphological control in electroless plating of nanostructured materials is underdeveloped compared to bulk nanoparticle synthesis. Our aim is to develop strategies for electroless plating with intrinsic shape control, enabling the direct deposition of films composed of high aspect ratio nanostructures .

In the present work we show that silver crystal nucleation and growth during electroless plating can be adjusted to induce the formation of different one- and two-dimensional nanomaterials, which are structurally related. By adding an iron-tartrate complex to a silver plating bath, we achieve selective two-dimensional growth and formation of micron-sized silver sheets of nanoscale (40 - 80 nm) thickness. Due to the suppression of random three-dimensional nucleation, this structural motif is preserved during all stages of the deposition. Thickness growth occurs via branching of new, separate silver sheets, which form stacks and are aligned with the underlying ones. Using this reaction, films of high aspect ratio silver nanoplatelets can be deposited on various substrate materials.

When sufficiently developed, the films possess continuous conduction paths and can be used as supporting, nanostructured electrodes, or employed directly as electrocatalyst. As an example for the latter case, we used silver structures for amperometric detection of hydrogen peroxide, in which a strong and fast response to the analyte was achieved. Silver nanolatelet films were also used as electrodes for CO2 reduction and as catalyst in reduction of 4-nitrophenol by NaBH₄.

Due to the wide functionality range of silver nanostructures and the shape-sensitivity of many of their properties, the approach described here provides a highly productive route toward materials for heterogeneous catalysis, sensing, plasmonics and (photo)electrochemistry, especially considering miniaturized designs such as microreactors and lab-on-a-chip sensors.

Prof. Israel Rubinstein passed away on October 21, 2017.