A cost-efficient approach for simultaneous scanning electrochemical microscopy and scanning ion conductance microscopy
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2020-06-17 |
| Journal | Monatshefte fĂŒr Chemie - Chemical Monthly |
| Authors | Stefan Wert, Simona BaluchovĂĄ, Karolina SchwarzovĂĄâPeckovĂĄ, Silvia SedlĂĄkovĂĄ, Andrew Taylor |
| Institutions | Czech Academy of Sciences, Institute of Physics, Charles University |
| Citations | 4 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Simultaneous SECM and SICM on Boron-Doped Diamond
Section titled âTechnical Documentation & Analysis: Simultaneous SECM and SICM on Boron-Doped DiamondâExecutive Summary
Section titled âExecutive SummaryâThis research highlights the critical need for high-quality, customized electrode materials, specifically Boron-Doped Diamond (BDD), for advanced scanning probe techniques. 6CCVD is uniquely positioned to supply the necessary materials and customization services to replicate and extend this work.
- Advanced Probe Development: A cost-efficient method was developed for fabricating dual-function probes capable of simultaneous Scanning Electrochemical Microscopy (SECM) and Scanning Ion Conductance Microscopy (SICM).
- Integrated Functionality: Probes feature an integrated ring ultramicroelectrode (UME) for electrochemical mapping and a pipette channel for non-contact topographical analysis.
- Critical Application: The probes were successfully utilized to investigate porous Boron-Doped Diamond (BDD) substrates, distinguishing between topographical features and electrochemical activity.
- Material Challenge Identified: SECM/SICM analysis revealed variations in electrochemical activity on the BDD surface, potentially caused by non-uniform boron dopingâa challenge 6CCVDâs precise MPCVD control can address.
- Probe Specifications: Functional ring UMEs were fabricated with diameters as small as 2 ”m and 25 ”m, requiring precise control over the underlying Platinum (Pt) film thickness (< 50 nm).
- 6CCVD Value Proposition: We provide the high-purity, custom-doped BDD substrates (up to 125mm) and specialized metalization services (e.g., Pt, Ti/Au) required for both the substrate and the probe fabrication process.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the research, detailing the material and experimental parameters:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Ring UME Diameter (Small) | 2 | ”m | Unpolished probe |
| Ring UME Diameter (Large) | 25 | ”m | Polished probe |
| Estimated Pt Film Thickness | < 50 | nm | Required for functional ring UME |
| BDD Deposition Temperature | ca. 750 | °C | MPCVD Substrate Temperature |
| BDD Microwave Power | 1150 | W | MPCVD Growth Parameter |
| BDD Gas Pressure | 50 | mbar | MPCVD Growth Parameter |
| BDD Methane Concentration | 0.5 | % | In Hydrogen (H2) |
| BDD Boron/Carbon Ratio (B/C) | 4000 | ppm | Heavy doping level |
| SECM Potential (Model Substrate) | +0.3 | V | Amperometric mode |
| SICM Potential (Model Substrate) | +0.2 | V | Ion conductance measurement |
| CV Scan Rate | 20 | mV s-1 | Probe characterization |
| SECM/SICM Scan Area (BDD) | 294 x 294 | ”m | Simultaneous mapping area |
Key Methodologies
Section titled âKey MethodologiesâThe experiment relied on precise MPCVD growth for the BDD substrate and a multi-step process for probe fabrication:
- BDD Substrate Preparation: Porous BDD was grown via a two-step MPCVD process (5 hours per step) on conductive p-Si wafers.
- Porous Template: A 4-5 ”m thick 3D template of nanodiamond seeded SiO2 nanofibers was spin-coated onto a planar BDD base layer.
- Boron Doping: Trimethylboron was introduced during MPCVD to achieve a high B/C ratio of 4000 ppm, ensuring high conductivity.
- Probe Base: Platinum-coated fused silica capillaries (emitters for electrospray ionization) were used as the probe structure.
- Insulation Layer: SU8.5 photoresist was applied under N2 flow, cured via UV light (350 nm), and heated (95 °C) to form the insulating layer.
- Ring UME Exposure: The tip was polished using 0.3 ”m alumina lapping sheets while flushing water, precisely exposing the Pt ring electrode to achieve the desired 2 ”m or 25 ”m diameter.
- Electrochemical Setup: The BDD substrate was mounted on a brass rod sealed with polyvinyl chloride and epoxy resin, with electrical contact established using silver conductive paint.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThis research demonstrates the need for highly controlled, customized diamond materials for cutting-edge electrochemistry and scanning probe microscopy. 6CCVDâs specialized MPCVD capabilities directly address the material requirements and challenges identified in this paper, particularly the need for uniform, heavily doped BDD.
Applicable Materials
Section titled âApplicable MaterialsâTo replicate or extend the investigation of advanced electrochemical surfaces, 6CCVD recommends the following materials:
- Heavy Boron-Doped PCD (Polycrystalline Diamond): Ideal for large-area electrochemical substrates (up to 125mm diameter) requiring high conductivity and chemical inertness, suitable for high-throughput SECM/SICM mapping.
- Custom BDD Substrates: We can precisely match the required 4000 ppm B/C doping ratio using our MPCVD systems, ensuring the necessary electrochemical properties. We offer substrates up to 10mm thick.
- Planar BDD Base Layers: We can supply the high-quality, planar BDD base layer required for the subsequent application of the porous template structure, ensuring optimal adhesion and electrical contact.
Customization Potential
Section titled âCustomization PotentialâThe success of both the probe and the substrate relies on precise dimensional and surface control. 6CCVD offers the following customization services:
| Requirement from Paper | 6CCVD Customization Capability | Benefit to Researcher |
|---|---|---|
| Porous BDD Substrate | Custom dimensions up to 125mm (PCD) | Enables larger, more complex experimental setups. |
| Non-Uniform Doping Issue | Precise, uniform boron doping control | Eliminates electrochemical variations caused by inconsistent B/C ratio. |
| Probe Metalization (Pt film) | Custom Metalization (Au, Pt, Pd, Ti, W, Cu) | We can deposit high-ppurity Pt films with controlled thickness (e.g., 50 nm range) for probe fabrication research. |
| Substrate Contact | Custom Metalization and Polishing | Providing Ti/Pt/Au contact pads on the BDD substrate for reliable electrical connection, replacing silver paint/epoxy methods. |
| Surface Finish | Ultra-low roughness polishing (Ra < 5nm for PCD) | Ensures a highly controlled, reproducible surface finish for baseline topographical studies. |
Engineering Support
Section titled âEngineering SupportâThe paper noted that variations in SECM current might be a consequence of non-uniform distribution of boron doping ratio within the BDD layer.
- 6CCVDâs in-house PhD team specializes in optimizing MPCVD growth parameters, including gas flow, pressure, and dopant concentration (like the 4000 ppm B/C ratio), to ensure uniform electrochemical activity across the entire diamond surface for similar SECM/SICM projects.
- We offer consultation on selecting the optimal diamond grade (SCD vs. PCD) and doping level for specific redox mediator systems (e.g., FcMeOH or Ru(NH3)6Cl3).
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly. Global shipping (DDU default, DDP available) ensures rapid delivery of specialized diamond materials worldwide.
View Original Abstract
Abstract A novel and cost-efficient probe fabrication method yielding probes for performing simultaneous scanning electrochemical microscopy (SECM) and scanning ion conductance microscopy (SICM) is presented. Coupling both techniques allows distinguishing topographical and electrochemical activity information obtained by SECM. Probes were prepared by deposition of photoresist onto platinum-coated, pulled fused silica capillaries, which resulted in a pipette probe with an integrated ring ultramicroelectrode. The fabricated probes were characterized by means of cyclic voltammetry and scanning electron microscopy. The applicability of probes was demonstrated by measuring and distinguishing topography and electrochemical activity of a model substrate. In addition, porous boron-doped diamond samples were investigated via simultaneously performed SECM and SICM. Graphic abstract
Tech Support
Section titled âTech SupportâOriginal Source
Section titled âOriginal SourceâReferences
Section titled âReferencesâ- 2012 - Scanning electrochemical microscopy