Publications by authors named "Natasha P Siepser"
Article Synopsis
- * Synthesizing nanocrystals with specific structures enhances catalysis by improving efficiency in CO reduction reactions (CORR), but their performance is often evaluated in averaged groups rather than individually.
- * This study uses advanced microscopy to analyze the performance of individual gold nanocrystals, revealing that certain structures (like {110}-terminated rhombohedra) are more effective in catalyzing CO reduction at low energy inputs.
Article Synopsis
- Single entity electrochemical (SEE) studies require isolated nanoparticles, which are achieved through electrospray deposition of colloidal nanoparticle solutions.
- Three electrospray parameters—spray distance, current, and emitter tip diameter—affect the deposition of single gold nano-octahedra (Au ODs).
- Optimal conditions resulted in a local surface density of 0.26 single particles per μm and a high success rate of 96.3% for single Au OD deposition.
Scanning ion conductance microscopy (SICM) has emerged as a versatile tool for studies of interfaces in biology and materials science with notable utility in biophysical and electrochemical measurements. The heart of the SICM is a nanometer-scale electrolyte filled glass pipette that serves as a scanning probe. In the initial conception, manipulations of ion currents through the tip of the pipette and appropriate positioning hardware provided a route to recording micro- and nanoscopic mapping of the topography of surfaces.
View Article and Find Full Text PDFWe describe a method for electrochemical measurement and synthesis based on the combination of a mobile micropipette and a microelectrode array, which we term the array microcell method (AMCM). AMCM has the ability to address single electrodes within a microelectrode array (MEA) and provides a simple, low-cost format to enable versatile electrochemical measurements. In AMCM, a droplet at the tip of a movable micropipette (inner diameter of 50 μm) functions as an electrochemical cell, in which the electrode area is defined by a microelectrode of the array.
View Article and Find Full Text PDFElectrocatalytic reduction reactions (i.e., the hydrogen evolution reaction (HER) and oxygen reduction reaction) at individual, faceted Au nanocubes (NCs) and nano-octahedra (ODs) expressing predominantly {100} and {111} crystal planes on the surface, respectively, were studied by nanoscale voltammetric mapping.
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