Banana Peel Biochar for Clean Energy Catalysts

ISEF Category: Energy: Sustainable Materials and Design

Subcategory: Biological Process and Design  ·  Difficulty: Intermediate  ·  Setup: School Lab  ·  Time: 1 to 2 Months

The Hook

A banana peel can become part of a cleaner fuel system. That sounds odd, but plant waste can be turned into porous carbon with useful surface chemistry. If you can test how that carbon affects catalyst performance, you are doing real materials research. This topic also connects kitchen waste, clean energy, and data you can measure.

What Is It?

Biochar is carbon-rich material made by heating plant matter without much oxygen. Think of it like a sponge made of carbon. A sponge has lots of pores, and those pores give other materials more surface to stick to. In this project, banana peel becomes the starting material, then you test whether the resulting carbon can help support a catalyst.

A catalyst support is the base material that holds active particles in place. The support matters because it can change how stable the catalyst stays, how much surface area it has, and how well charge moves across it. Cyclic voltammetry is one way to probe that behavior. It measures how current changes as you sweep voltage back and forth, which gives you clues about electron transfer and surface activity.

Why This Is a Good Topic

This makes a strong science fair topic because you can change one clear variable, then measure a response with real data. You can compare different feedstocks, different activation methods, or different catalyst loadings and see how the signal changes. The project connects to waste valorization, cleaner fuel production, and low-cost materials design. You can also learn how to make controls, build a calibration plan, and use graphs to defend your claim.

Research Questions

• How does the banana peel biochar activation method affect cyclic voltammetry peak current?
• What is the effect of biochar particle size on the electrical response of the catalyst support?
• Does increasing the amount of banana peel biochar change the stability of the voltammetry signal?
• To what extent does washed banana peel biochar differ from unwashed biochar in electrochemical performance?
• Which preparation condition gives the highest effective surface area signal in cyclic voltammetry?
• How does banana peel biochar compare with another plant-based carbon support under the same test conditions?

Basic Materials

• Banana peels, cleaned and dried.
• Heat-safe container or crucible for carbonization.
• School furnace, muffle furnace, or controlled high-heat setup.
• Mortar and pestle or grinder for making uniform particles.
• Sieves or mesh screens for separating particle sizes.
• Balance with 0.01 g or better precision.
• Hobbyist potentiostat.
• Working, reference, and counter electrodes.
• Conductive carbon ink or electrode paste.
• Beakers or small electrochemical cells.
• Deionized water.
• Ethanol or isopropyl alcohol.
• Filter paper.
• Gloves, goggles, and lab coat.

Advanced Materials

• Tube furnace with gas control.
• Activation agent such as KOH or H3PO4, if approved by your lab.
• Surface area analysis access, such as BET instrumentation.
• Scanning electron microscope access for pore and surface imaging.
• X-ray diffraction access for carbon structure checks.
• Raman spectroscopy access for carbon ordering.
• Potentiostat with impedance capability.
• Standard redox probe for electrochemical comparison.
• Analytical balance with 0.001 g precision.
• Vacuum filtration setup.
• Inert gas supply for controlled carbonization.
• Computer with data analysis software.

Software & Tools

• ImageJ: Measures electrode surface images and helps compare texture or pore-like features.
• Python: Organizes voltammetry data, fits curves, and makes publication-style plots.
• RStudio: Runs statistics and compares groups with clear visual summaries.
• Excel: Tracks sample prep, labels runs, and makes quick graphs.
• Potentiostat software: Collects cyclic voltammetry scans and exports raw current-voltage data.

Experiment Steps

1. Define the exact claim you want to test, such as whether banana peel biochar improves a catalyst support signal more than a comparison carbon.
2. Choose one main variable, such as activation method, particle size, or loading level, and keep the rest constant.
3. Design a control plan that includes a blank electrode, a baseline carbon support, and repeated trials.
4. Plan how you will turn raw voltammetry scans into one clean measurement, such as peak current, peak separation, or area under the curve.
5. Decide how you will check whether the signal comes from the support itself, the catalyst, or contamination from the banana peel material.
6. Set up your analysis plan before you collect data, including how you will compare groups and report uncertainty.

Common Pitfalls

• Using banana peel that still has sugar or pulp on it, which can change the carbon chemistry and muddy the results.
• Making biochar with uneven heating, which creates samples that cannot be compared fairly.
• Packing the electrode differently each time, which changes the measured current more than the material does.
• Skipping a carbon-only control, which makes it hard to tell whether the signal comes from the support or the catalyst.
• Reading voltammetry peaks from noisy scans without repeating trials, which can turn random fluctuation into a false trend.

What Makes This Competitive

A stronger project goes beyond making biochar and asking whether it works. You can compare multiple preparation routes, quantify electrochemical behavior, and connect the signal to physical structure. Good controls matter a lot here, especially if you separate support effects from catalyst effects. If you pair voltammetry with a structure check, your claim becomes much more convincing.

Project Variations

• Test orange peel, coconut shell, or coffee grounds as a comparison carbon feedstock.
• Compare physical activation and chemical activation to see which produces a better catalyst support.
• Study how biochar performance changes when you pair it with different catalyst metals or redox probes.

Learn More

• NIH PubMed: Search for review articles on biochar, activated carbon, and catalyst supports.
• NASA Earthdata: Find background on biomass, carbon cycling, and waste streams.
• USGS Water Science School: Read about carbon materials, adsorption, and environmental testing concepts.
• MIT OpenCourseWare: Search materials science and electrochemistry course notes for carbon, electrodes, and surface analysis.
• Journal of Power Sources: Search the journal for electrochemical studies on carbon supports and biomass-derived materials.
• Bioresource Technology: Search for peer-reviewed papers on biomass conversion, biochar, and waste-to-value materials.