Coffee Grounds-Derived CNPs for Efficient Cr(VI) Water Remediation

Area of Science:

• Materials Science
• Environmental Science
• Nanotechnology

Background:

• Carbon nanomaterials possess unique sp2/sp3 carbon backbones and surface chemistries, enabling diverse applications.
• Carbon dots and carbon nanoparticles are key carbon nanomaterials with nanoscale dimensions.
• Sustainable sourcing of carbon nanomaterials is crucial for environmental applications.

Purpose of the Study:

• To develop a sustainable, cost-effective, and eco-friendly method for producing carbon nanoparticles.
• To characterize the synthesized carbon nanoparticles and confirm their properties.
• To investigate the potential of these nanoparticles in reducing heavy metal ions.

Main Methods:

• Spent coffee grounds were oxidized using hydrogen peroxide at controlled temperatures.
• Atomic Force Microscopy (AFM) was used for dimensional analysis.
• Spectroscopic techniques including fluorescence, UV-Vis absorption, FT-IR, and Raman spectroscopy were employed for characterization.

Main Results:

• Carbon nanoparticles approximately 10 nm in size were successfully synthesized.
• The nanoparticles exhibited characteristic carbon dot emission and absorption properties.
• Presence of phosphorus heteroatoms and carbonyl/carboxyl surface groups was identified.

Conclusions:

• A simple, green synthesis route for carbon nanoparticles from waste coffee grounds was established.
• The synthesized carbon nanoparticles demonstrated efficient reduction of Mn(VII) and Cr(VI) under specific pH conditions.
• These findings highlight the potential of upcycled carbon nanomaterials for environmental remediation.