Aligned Carbon Nanotube Electrodes With Uniform Metal Oxide Coating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing supercapacitor electrodes face challenges due to the difficulty in controlling porosity and corrosion issues with aluminum supports when depositing metal oxides like MnO2 using anodic electrochemical methods, which affect capacitance and performance.
Innovation Solution
A process involving vertically aligned carbon nanotubes on a metallic support with a nitrate-based electrolytic solution for electrochemical deposition of metal oxides over the entire length of the nanotubes, ensuring a homogeneous and corrosion-resistant coating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If anodic electrochemical deposition is used to deposit metal oxide on aluminum support, then metal oxide coating is achieved, but corrosion of aluminum support occurs
Solution Approach 1:
Vertically aligned carbon nanotubes serve as an intermediary layer between the aluminum support and metal oxide coating. The nanotubes are first grown on the aluminum substrate, then metal oxide is deposited on the nanotubes through electrochemical deposition. This intermediary structure prevents direct contact between the aluminum and electrolyte, eliminating corrosion while enabling homogeneous metal oxide coating formation.
Solution Approach 2:
The invention changes the deposition parameters by using electrochemical deposition at controlled potentials (0.2-0.6 V vs Ag/AgCl) in the presence of carbon nanotubes. This parameter control allows metal oxide to deposit preferentially on the nanotube surfaces rather than directly on the aluminum, achieving homogeneous coating without triggering aluminum corrosion.
2Quantity of substance
If metal oxide is deposited directly on aluminum support, then capacitance is improved, but coating homogeneity is difficult to control
Solution Approach 1:
The vertically aligned carbon nanotubes form a porous, high-surface-area structure that serves as an ideal template for metal oxide deposition. The porous nature of the nanotube array allows electrolyte penetration and uniform electrochemical deposition of metal oxide throughout the structure, achieving homogeneous coating with high surface area for capacitance enhancement.
Solution Approach 2:
The invention transitions from two-dimensional planar deposition on aluminum to three-dimensional deposition on vertically aligned nanotubes. This dimensional change provides uniform surface distribution and facilitates homogeneous metal oxide coating throughout the electrode structure, maximizing capacitance while ensuring uniformity.
3Use of energy by moving object
If vertically aligned carbon nanotubes are used, then energy storage capability is improved, but manufacturing complexity increases
Solution Approach 1:
The invention merges two separate processes (carbon nanotube growth and metal oxide deposition) into an integrated electrode fabrication approach. By combining the high energy storage capability of vertically aligned carbon nanotubes with the pseudocapacitive properties of metal oxide coating in a single structured electrode, the system achieves enhanced energy storage while managing manufacturing complexity through process integration.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method achieves high capacitance and improved performance by ensuring a homogeneous metal oxide coating on carbon nanotubes, suitable for various metal supports, including aluminum, enhancing the energy storage capabilities of supercapacitors.
Implementation Method 1
a) synthesizing, on a metal support, a carpet of vertically aligned carbon nanotubes
Implementation Method 2
b) electrochemically depositing said metal oxide on said carbon nanotubes from an electrolytic solution comprising at least one precursor of said metal oxide
Implementation Method 3
by anodic electrochemical means
Data Source
Figure 1~2
Figure 3A~3C
Figure 4A~5
AI summary
The present invention relates to a method for preparing an electrode comprising a metal substrate, vertically aligned carbon nanotubes and a metal oxide deposited over the entire length of said vertically aligned carbon nanotubes, said method comprising the following consecutive steps: (a) synthesising, on a metal substrate, a mat of vertically aligned carbon nanotubes; (b) electrochemically depositing the metal oxide on said carbon nanotubes from an electrolytic solution comprising at least one precursor of said metal oxide and at least one nitrate, said electrochemical deposition being carried out by a chronopotentiometry technique. The present invention also relates to the electrode thus prepared and to the uses thereof.