Elevating Platinum to Volumetric Capacitance: High Surface Area Electrodes through Reactive Pt Sputtering

Advanced Healthcare Materials, vol. 13, pp. e2302400

Abstract

Abstract Platinum is the most widespread electrode material used for implantable biomedical and neuroelectronic devices, motivating exploring ways to improve its performance and understand its fundamental properties. Using reactive magnetron sputtering, PtOx is prepared, which upon partial reduction yields a porous thin‐film form of platinum with favorable properties, notably record‐low impedance values outcompeting other reports for platinum‐based electrodes. It is established that its high electrochemical capacitance scales with thickness, in the way of volumetric capacitor materials like IrOx and poly(3,4‐ethylenedioxythiophene), PEDOT. Unlike these two well‐known analogs, however, it is found that PtOx capacitance is not caused by reversible pseudofaradaic reactions but rather due to high surface area. In contrast to IrOx, PtOx is not a reversible valence‐change oxide, but rather a porous form of platinum. The findings show that this oxygen‐containing form of Pt can place Pt electrodes on a level competitive with IrOx and PEDOT. Due to its relatively low cost and ease of preparation, PtOx can be a good choice for microfabricated bioelectronic devices.

Authors 5

1. Maciej Gryszel

   Linköping University

   Affiliation as printed

   Laboratory of Organic Electronics Department of Science and Technology Linköping University Bredgatan 33 Norrköping 60174 Sweden

2. Marie Jakešová

   Central European Institute of Technology · Brno University of Technology

   Affiliation as printed

   Bioelectronics Materials and Devices Laboratory Central European Institute of Technology Brno University of Technology Purkyňova 123 Brno 61200 Czech Republic

3. Xuan Thang Vu Aachen Institute of Materials in Electrical Engineering 1

   RWTH Aachen University

   Affiliation as printed

   Institute of Materials in Electrical Engineering 1 RWTH Aachen University 52074 Aachen Germany

   Institute of Materials in Electrical Engineering 1, RWTH Aachen University, 52074 Aachen, Germany

4. Sven Ingebrandt Aachen Institute of Materials in Electrical Engineering 1

   RWTH Aachen University

   Affiliation as printed

   Institute of Materials in Electrical Engineering 1 RWTH Aachen University 52074 Aachen Germany

   Institute of Materials in Electrical Engineering 1, RWTH Aachen University, 52074 Aachen, Germany

5. Eric Daniel Głowacki corresponding

   Central European Institute of Technology · Brno University of Technology

   Affiliation as printed

   Bioelectronics Materials and Devices Laboratory Central European Institute of Technology Brno University of Technology Purkyňova 123 Brno 61200 Czech Republic