Ni-Coated Diamond-like Carbon-Modified TiO2 Nanotube Composite Electrode for Electrocatalytic Glucose Oxidation

At a Glance

Metadata	Details
Publication Date	2022-09-08
Journal	Molecules
Authors	Yi Kang, Xuelei Ren, Yejun Li, Zhiming Yu
Institutions	Central South University, Third Xiangya Hospital
Citations	11
Analysis	Full AI Review Included

Technical Documentation & Analysis: High-Performance Non-Enzymatic Glucose Sensors

This document analyzes the research on Ni-DLC/TiO₂ Nanotube composite electrodes for electrocatalytic glucose oxidation, identifying key technical requirements and positioning 6CCVD’s advanced MPCVD diamond materials as superior, scalable solutions for next-generation biosensors.

Executive Summary

Application Focus: Development of a highly sensitive and stable non-enzymatic glucose sensor utilizing a composite electrode structure (Ni-DLC/TiO₂ Nanotubes).
Core Achievement: The synergistic effect between Ni nanoparticles and the conductive Diamond-Like Carbon (DLC) film significantly enhanced the electrocatalytic oxidation performance of glucose.
Fabrication Method: A combination of anodic oxidation (for TiO₂ nanotubes), pulsed electrodeposition (for Ni nanoparticles), and RF bias-assisted magnetron sputtering (for the Ni-DLC film) was employed.
Performance Metrics: Achieved a high sensitivity of 1063.78 µA·mM⁻¹·cm⁻² in the low concentration range (0.99-3.00 mM).
Detection Limit: Demonstrated an ultra-low detection limit (LOD) of 0.53 µM (S/N = 3), suitable for high-precision biochemical analysis.
Stability: The composite electrode exhibited excellent long-term stability, retaining 82.6% of its initial current response after one month of storage.
6CCVD Value Proposition: Boron-Doped Diamond (BDD) from 6CCVD offers a chemically inert, highly conductive, and stable carbon substrate, providing a high-performance alternative to the complex, multi-layer DLC/TiO₂ structure for advanced electrochemical sensing.

Technical Specifications

The following hard data points were extracted from the performance characterization of the Ni-DLC/TiO₂ composite electrode:

Parameter	Value	Unit	Context
Maximum Sensitivity	1063.78	µA·mM⁻¹·cm⁻²	Glucose concentration range 0.99-3.00 mM
Detection Limit (LOD)	0.53	µM	Calculated based on S/N = 3
Linear Range 1 (Low Conc.)	0.99-3.00	mM	High sensitivity region (R² = 0.9981)
Linear Range 2 (High Conc.)	3.00-22.97	mM	Lower sensitivity region (R² = 0.9921)
Long-Term Stability	82.6	%	Current response retained after 1 month
Working Electrode Area	0.25	cm²	Packaged sample size (5 x 5 mm²)
Applied Potential (Chronoamperometry)	0.55	V	Used for glucose oxidation detection
Background Electrolyte	0.5	M	NaOH solution (Alkaline media)

Key Methodologies

The composite electrode was prepared using a three-step fabrication process:

TiO₂ Nanotube Array (TNT) Formation (Anodic Oxidation):
- Substrate: Polished Ti sheet (99.99%, 5 x 5 x 1.5 mm).
- Pre-treatment: Chemical polishing in NaF:HNO₃:H₂O (2:18:80 m/m).
- Anodizing Parameters: Applied voltage of 25 V for 1 hour.
- Electrolyte: Glycerol solution containing 0.2-7 M NH₄F.
Ni Nanoparticle Deposition (Pulsed Electrodeposition):
- System: Three-electrode system (TNT working electrode, Ni counter electrode, Ag/AgCl reference).
- Cathode Pulse Current Density: -160 mA/cm² (8 ms duration).
- Anode Pulse Current Density: +160 mA/cm² (2 ms duration).
- Turn-Off Time: 1000 ms.
- Total Deposition Time: 10 minutes.
- Temperature: Maintained at 38 °C.
Ni-DLC Film Deposition (RF Bias-Assisted Magnetron Sputtering):
- Gas Flow Ratio (Ar:C₂H₂): 16:6 sccm.
- Deposition Pressure: 1.0 Pa.
- RF Power: 200 W.
- Bias Voltage: 25 V.
- Sputtering Time: 5 minutes.

6CCVD Solutions & Capabilities

The research highlights the critical role of the carbon layer (DLC) in providing conductivity, stability, and a robust anchoring platform for Ni nanoparticles. 6CCVD specializes in MPCVD diamond, which offers superior electrochemical performance and stability compared to DLC films, enabling researchers to achieve higher sensitivity and long-term reliability.

Research Requirement/Challenge	6CCVD Solution & Advantage	Applicable 6CCVD Material
High Conductivity & Chemical Inertness: DLC used to improve electron transfer and stability.	Boron-Doped Diamond (BDD): BDD is the ultimate conductive electrode material, offering a wider potential window, lower background current, and unmatched chemical inertness, eliminating the need for complex DLC modification layers.	Heavy Boron-Doped PCD or SCD
Scalability & Manufacturing: Small 5 x 5 mm² electrodes used; scaling is complex with multi-step TNT/DLC process.	Large Format BDD Wafers: 6CCVD supplies conductive PCD and BDD wafers up to 125 mm in diameter, facilitating high-volume manufacturing and large-scale sensor array development.	PCD Wafers (up to 125mm)
Surface Quality for Nanoparticle Anchoring: DLC surface roughness affects uniformity and fouling.	Precision Polishing: 6CCVD provides ultra-smooth surfaces (Ra < 1nm for SCD, Ra < 5nm for PCD), ensuring highly uniform electrodeposition of catalytic nanoparticles (Ni, Pt, Au) and minimizing adsorption of oxidation products (fouling).	Polished SCD or PCD
Custom Metal Catalyst Integration: Ni was deposited via electrodeposition.	In-House Metalization Services: We offer internal capabilities for depositing thin films of catalytic metals (Au, Pt, Pd, Ti, W, Cu, and Ni precursors) directly onto the diamond surface, ensuring superior adhesion and stability compared to electrodeposited NPs.	Metalized BDD/PCD

Engineering Support

The use of DLC in this paper demonstrates a clear need for high-performance, stable carbon electrodes in non-enzymatic glucose sensor development. 6CCVD’s in-house PhD team specializes in the electrochemical properties of diamond and can assist researchers in transitioning from DLC or other carbon substrates to optimized Boron-Doped Diamond (BDD) for similar biosensing and electrocatalytic projects. We provide consultation on doping levels, surface termination, and metalization schemes tailored to specific alkaline oxidation environments.

For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.

View Original Abstract

In this paper, a Ni and diamond-like carbon (DLC)-modified TiO2 nanotube composite electrode was prepared as a glucose sensor using a combination of an anodizing process, electrodeposition, and magnetron sputtering. The composition and morphology of the electrodes were analyzed by a scanning electron microscope and energy dispersive X-ray detector, and the electrochemical glucose oxidation performance of the electrodes was evaluated by cyclic voltammetry and chronoamperometry. The results show that the Ni-coated DLC-modified TiO2 electrode has better electrocatalytic oxidation performance for glucose than pure TiO2 and electrodeposited Ni on a TiO2 electrode, which can be attributed to the synergistic effect between Ni and carbon. The glucose test results indicate a good linear correlation in a glucose concentration range of 0.99-22.97 mM, with a sensitivity of 1063.78 μA·mM−1·cm−2 and a detection limit of 0.53 μM. The results suggest that the obtained Ni-DLC/TiO2 electrode has great application potential in the field of non-enzymatic glucose sensors.

Tech Support

Original Source

DOI: https://doi.org/10.3390/molecules27185815

References

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2015 - Electrochemical Performance and Biosensor Application of TiO2 Nanotube Arrays with Mesoporous Structures Constructed by chemical Etching [Crossref]
2016 - Ni(OH)2/MoSx nanocomposite electrodeposited on a flexible CNT/PI membrane as an electrochemical glucose sensor: The synergistic effect of Ni(OH)2 and MoSx [Crossref]
2009 - Nonenzymatic glucose sensor based on renewable electrospun Ni nanoparticle-loaded carbon nanofiber paste electrode [Crossref]
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2013 - Nickel/Copper nanoparticles modified TiO2 nanotubes for non-enzymatic glucose biosensors [Crossref]
2013 - Electrochemical deposition of nickel nanoparticles on reduced graphene oxide film for nonenzymatic glucose sensing [Crossref]