Electrochemical Nanoscale Characterization of 3D-Printed Sensors by Scanning Electrochemical Cell Microscopy (SECCM)

• Grant number: 25/16175-1
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: September 01, 2025
• End date: August 31, 2027
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Analytical Chemistry
• Principal Investigator: Thiago Regis Longo Cesar da Paixão
• Grantee: William Barros Veloso
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 23/00246-1 - Miniaturized large-scale devices for in-situ analysis: fabrication, characterization and applications, AP.TEM

Abstract

3D printing has revolutionized the fabrication of sensors and biosensors, enabling rapid, automated, and low-cost production of on-demand devices, with minimal waste generation and high scalability. This technology has driven the development of electrochemical sensors for applications in healthcare, environmental monitoring, quality control, and illicit substance detection. In these devices, electrochemical reactions occur on electrodes composed of thermoplastic polymers, such as polylactic acid (PLA), combined with carbon-based conductive materials. The composite nature of these surfaces results in high morphological, chemical, and structural heterogeneity.Currently, the electrochemical activity of such sensors is mainly characterized using macroscopic techniques, which only provide averaged values of the electrode's properties. Nanoscale investigation will enable mapping of conductive and non-conductive regions, estimation of kinetic parameters with nanometric spatial resolution, and identification of catalytic sites that govern overall activity. This information will be crucial for optimizing printing parameters and developing more sensitive and selective designs.This project proposes to investigate the nanoscale electrochemical activity of 3D-printed sensors using Scanning Electrochemical Cell Microscopy (SECCM). Combining SECCM mapping with spectroscopic techniques, such as Raman and XPS, will allow the correlation of structure and electrochemical performance, providing valuable insights for advancing the design of 3D-printed sensors.