Nagaland University & University of Science and Technology Beijing turn waste apple leaves into 96.2% corrosion shield for copper

Exam-focused facts from the 21 January 2026 current affairs briefing.

Key facts

Carbon quantum dots derived from discarded apple leaves delivered 96.2% corrosion protection for copper in acidic environments.
The apple-leaf carbon quantum dots (ACDs) achieved 94% inhibition efficiency at low concentrations, rising to 96.2% over longer exposure.
Using a green hydrothermal process, the team converted apple leaves into sulfur- and nitrogen-doped nanoscale carbon particles that form a compact, stable protective film on copper.
Advanced theoretical modelling revealed that specific nitrogen-containing groups anchor the protective layer to the metal surface.
The study supports circular economy models by converting agricultural residue into high-value functional nanomaterials.