Skip to content
6CCVD Research

Nano-Needle Boron-Doped Diamond Film with High Electrochemical Performance of Detecting Lead Ions

At a Glance

Section titled “At a Glance”
MetadataDetails
Publication Date2023-10-31
JournalMaterials
AuthorsXiaoxi Yuan, Mingchao Yang, Xu Wang, Yong Zhu, Feng Yang
InstitutionsJilin University, Jilin Engineering Normal University
Citations1
AnalysisFull AI Review Included

Executive Summary

Section titled “Executive Summary”

This analysis summarizes the development and performance of a Nano-Needle Boron-Doped Diamond (NNBDD) film electrode optimized for trace lead ion (Pb2+) detection.

  • Novel Fabrication Route: A simple, economical, and template-free method was used, involving Microwave Plasma Chemical Vapor Deposition (MPCVD) to create a diamond/non-diamond carbon (NDC) composite, followed by annealing at 800 °C to selectively etch the NDC phase.
  • Enhanced Surface Area: The resulting NNBDD structure exhibits a large specific surface area, providing 7 times the estimated electrochemical active sites compared to the initial composite film.
  • Superior Detection Performance: The electrode achieved a low detection limit (LOD) of 0.32 ”gL-1 for Pb2+ using Differential Pulse Anodic Stripping Voltammetry (DPASV), significantly outperforming many previously reported BDD electrodes.
  • Wide Linear Range: The sensor demonstrated excellent linearity across a wide concentration range, from 1 to 80 ”gL-1.
  • Tip-Enhanced Sensitivity: COMSOL Multiphysics simulations confirmed that the high-curvature nanoneedle tips enhance the local electric field (up to 7.47 x 106 V/m for 5 nm tips), which facilitates the precipitation and detection of Pb2+ at low concentrations.
  • Robustness and Selectivity: The NNBDD sensor showed high reproducibility (3.8% Relative Standard Deviation) and good anti-interference properties against common metal ions (Cd2+, Zn2+, Ca2+, Mg2+, Na+, Al3+, Fe3+).

Technical Specifications

Section titled “Technical Specifications”
ParameterValueUnitContext
Detection Limit (LOD)0.32”gL-1Pb2+ detection via DPASV
Linear Range1 to 80”gL-1Pb2+ concentration
Reproducibility (RSD)3.8%For 80 ”gL-1 Pb2+ concentration
Surface Area Enhancement7timesNNBDD vs. NNBDD/NDC composite
Boron Concentration ([B])3.19 x 1020cm-3Calculated from Raman spectroscopy
Nanoneedle Grain Length50-250nmNNBDD morphology
Max Simulated Electric Field (Emax)7.47 x 106V/mFor 5 nm tip radius
NDC Etching Temperature800°CAnnealing process in air
Diamond Characteristic Peak1332cm-1Raman shift after annealing
NDC Characteristic Peak1550cm-1Raman shift (disappears after annealing)
Charge Transfer Resistance (Rct)LowerΩNNBDD compared to NNBDD/NDC composite

Key Methodologies

Section titled “Key Methodologies”

The NNBDD films were fabricated on P-type Si substrates using a two-step process: MPCVD deposition followed by thermal annealing.

  1. Substrate Preparation:

    • Mirror-polished Si substrates were scratched using 5 nm nanodiamond powders for 30 min.
    • Substrates were ultrasonicated in an acetone solution containing nanodiamond powder for 60 min to establish nucleation sites.

  2. Composite Film Deposition (MPCVD):

    • System: Microwave Plasma Chemical Vapor Deposition (2.45 GHz).
    • Gas Sources: Methane (CH4), Hydrogen (H2), and liquid trimethyl borate (B(OCH3)3) as the boron source.
    • Flow Rate: CH4/H2/B flow rate set to 20/200/2 sccm.
    • Result: Deposition for 6 hours yielded a nano-needle boron-doped diamond/non-diamond carbon (NNBDD/NDC) composite film.

  3. NDC Etching and NNBDD Fabrication:

    • Annealing: The composite film was annealed in a quartz tube at 800 °C for 15 min in the air. This step selectively etched the NDC phase.
    • Cooling: Rapid cooling (within 60 s) was achieved by quickly pulling out the porcelain boat, retaining the NNBDD structure.

  4. Electrochemical Detection (DPASV):

    • Electrolyte: 0.1 M acetate buffer (pH = 5.0).
    • Accumulation Conditions: Pre-deposition accumulation at -0.8 V for 270 s.
    • Stripping: Differential Pulse Anodic Stripping Voltammetry (DPASV) was used to measure the stripping current of deposited Pb.

Commercial Applications

Section titled “Commercial Applications”

The NNBDD technology, leveraging the inherent stability and wide potential window of BDD combined with enhanced nanostructure surface area, is highly relevant for sensitive electrochemical sensing in demanding environments.

  • Environmental Monitoring:
    • Trace heavy metal detection (e.g., Pb2+, Cd2+, Zn2+) in drinking water and wastewater, meeting or exceeding stringent regulatory limits (e.g., 6 ”gL-1 for Pb2+).
    • Real-time, in situ monitoring of pollutants due to the robustness and portability of the DPASV method.
  • Industrial Process Control:
    • Monitoring trace contaminants in chemical processing baths, plating solutions, and industrial effluents where high chemical inertness is required.
  • High-Performance Electrochemical Sensing:
    • Development of highly sensitive sensors for various electroactive organic and inorganic species, utilizing the large electrochemical potential window of BDD.
  • Biomedical and Clinical Diagnostics:
    • Fabrication of low-noise, biocompatible electrodes for detecting biomarkers or drugs, leveraging the low background current characteristic of BDD.
View Original Abstract

Nano-needle boron-doped diamond (NNBDD) films increase their performance when used as electrodes in the determination of Pb2+. We develop a simple and economical route to produce NNBDD based on the investigation of the diamond growth mode and the ratio of diamond to non-diamond carbon without involving any templates. An enhancement in surface area is achievable for NNBDD film. The NNBDD electrodes are characterized through scanning electron microscopy, Raman spectroscopy, X-ray diffraction, cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse anodic stripping voltammetry (DPASV). Furthermore, we use a finite-element numerical method to research the prospects of tip-enhanced electric fields for sensitive detection at low Pb2+ concentrations. The NNBDD exhibits significant advantages and great electrical conductivity and is applied to detect trace Pb2+ through DPASV. Under pre-deposition accumulation conditions, a wide linear range from 1 to 80 ”gL−1 is achieved. A superior detection limit of 0.32 ”gL−1 is achieved for Pb2+, which indicates great potential for the sensitive detection of heavy metal ions.

Tech Support

Section titled “Tech Support”

Original Source

Section titled “Original Source”

References

Section titled “References”
  1. 2019 - Conductive diamond: Synthesis, properties, and electrochemical applications [Crossref]
  2. 2014 - Diamond Nanowires: Fabrication, Structure, Properties, and Applications [Crossref]
  3. 2022 - Recent electroanalytical applications of boron-doped diamond electrodes [Crossref]
  4. 2023 - Modification-free boron-doped diamond as a sensing material for direct and reliable detection of the antiretroviral drug nevirapine [Crossref]
  5. 1996 - Hydrogen and Oxygen Evolution on Boron-Doped Diamond Electrodes [Crossref]
  6. 2008 - Anodic Deposition of RuOx·nH2O at Conductive Diamond Films and Conductive Diamond Powder for Electrochemical Capacitors [Crossref]
  7. 2008 - Nanocrystalline diamond: In vitro biocompatibility assessment by MG63 and human bone marrow cells cultures [Crossref]
  8. 1997 - Corrosion studies of CVD diamond coated molybdenum, evaluation of equivalent circuit and the effect of pinholes in diamond film on cyclic voltammetric behavior [Crossref]
  9. 2015 - Porous diamond with high electrochemical performance [Crossref]

Reads Similar to This

A FLEXIBLE, LARGE-SCALE DIAMOND-POLYMER CHEMICAL SENSOR FOR NEUROTRANSMITTER DETECTION Photoelectrochemical Modelling of Semiconducting Electrodes for Neural Interfacing A Nanograss Boron and Nitrogen Co-Doped Diamond Sensor Produced via High-Temperature Annealing for the Detection of Cadmium Ions