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Abstract Light addressable electrochemical (LAE) sensors have seen great utility in the past several years because they enable multiple localized electrochemical measurements to be performed on a single macroscopic electrode, opening up applications in imaging, biosensing, surface patterning, and multiplexing. In this study, we investigated the effects of electrodeposition on the formation of LAE sensors formed between n‐Si and electrodeposited Pt. We prepared sensors by electrodepositing Pt onto freshly‐etched n‐Si under a variety of conditions, varying the Pt precursor concentration, electrodeposition time, supporting electrolyte, and potential waveform. We characterized the sensors using a combination of atomic force microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry. This study shows that the electrodeposition parameters have a dramatic impact on the morphology of the electrodeposited surfaces, sensor stability, and sensitivity towards H2O2. Specifically, we observed that continuous Pt films prepared with a higher Pt precursor concentration were more stable and had better linearity, higher sensitivity, and broader dynamic range than those prepared with a lower Pt precursor concentration. The stability and increased H2O2sensing performance correlate strongly with an increase in the Pt islands which make up the film. These data highlight that the morphology of the metal in semiconductor/metal junction LAE sensors has an impact on important performance metrics like stability and sensitivity. They also demonstrate the need for semiconductor/metal LAE sensors to be studied using micro‐ and nanoscale imaging techniques in order to more deeply understand their performance characteristics.
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Highly Porous Gold Electrodes – Preparation and Characterization
Abstract Gold screen printed electrodes (Au‐SPEs) were treated electrochemically to produce a micro‐rough pattern increasing the real electrode surface. The procedure based on the Dynamic Hydrogen Bubble Template (DHBT) method included electrochemical deposition of Au layers onto the surface of the Au‐SPEs, followed by a reductive process at −3 V (vs. Ag/AgCl) leading to formation of H2bubbles, which produced pores in the Au multilayer. The morphology of the micro‐porous Au electrode was characterized by scanning electron microscopy (SEM), surface mapping, surface profilometry, and confocal microscopy. The electrode surface morphology was controlled by the time of the electrode reductive treatment (H2evolution) and the optimized condition resulting in the best surface structuring was found. Notably, the surface roughness leading to the highest electrode surface area was significantly increased compared to previously reported results with Au‐SPEs.
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- Award ID(s):
- 1939063
- PAR ID:
- 10446084
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemElectroChem
- Volume:
- 9
- Issue:
- 9
- ISSN:
- 2196-0216
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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