Expert-level nanomaterials engineering covering synthesis, characterization, properties at nanoscale, nanocomposites, safety, and industrial applications of nanomaterials.
Surface to volume ratio: increases dramatically at nanoscale, dominates properties. Quantum confinement: electronic energy levels discretize below de Broglie wavelength. Melting point depression: nanoparticles melt at lower temperature than bulk. Superparamagnetism: single domain magnetic particles below critical size. Plasmonic resonance: free electrons in metal nanoparticles resonate with light.
Top-down: ball milling, lithography, etching from bulk material. Bottom-up: chemical vapor deposition, sol-gel, hydrothermal, self-assembly. CVD for CNTs: carbon source decomposes over catalyst at high temperature. Colloidal synthesis: control nucleation and growth in solution for nanoparticles. Atomic layer deposition: conformal nanoscale thin film coating.
Polymer matrix: carbon nanotube or graphene reinforcement, percolation threshold. Metal matrix: nanoparticle dispersion strengthening. Ceramic matrix: CNT toughening, improved fracture toughness. Dispersion: challenge to uniformly disperse without agglomeration.
Exposure routes: inhalation most critical for nanoparticles. Biopersistence: fibers and needles more toxic than spheres of same composition. Regulation: evolving regulatory framework, precautionary approach recommended. Containment: engineering controls and PPE to minimize worker exposure.
| Pitfall | Fix |
|---|---|
| Agglomeration negating nanoscale effects | Optimize surface chemistry for stable dispersion |
| Assuming bulk properties apply at nanoscale | Measure properties of actual nanomaterial |
| Insufficient safety precautions | Use fume hood and appropriate PPE for all nanomaterial work |
| Poor dispersion in nanocomposites | Use surface functionalization and processing optimization |