Nanoparticle Superlattice Assembly and Optical Properties

Nanoparticle superlattices are ordered arrays of nanoscale building blocks arranged into extended crystalline architectures. Assembly methods include DNA-mediated binding, ligand-directed colloidal crystallisation and capillary-force–driven organisation. Control over particle shape, size, surface chemistry and interparticle spacing enables tuning of collective optical phenomena, such as plasmonic coupling, Mie-type resonances and emergent magnetic responses. These superlattices can behave as metasurfaces or bulk metamaterials, exhibiting high and even negative refractive indices, angle- and polarization-independent absorbance, photonic bandgaps and dynamic refractive modulation. Advances in real-space imaging and in situ manipulation have revealed kinetic pathways that govern lattice symmetry, facet selection and mechanical stability, laying the groundwork for scalable fabrication of functional optical coatings, sensors, photocatalysts and nonlinear photonic devices.

Research from Nature Portfolio

Recent studies have demonstrated that colloidal nanocrystals of varying shape can be organised into large-area metasurfaces by simple wet-chemical methods, yielding structures with near-ideal absorbance tunable from visible to mid-infrared wavelengths. These metasurfaces exploit extreme in-plane electromagnetic coupling controlled by particle size and spacing to achieve perfect-absorbance conditions. Other work has employed DNA strands to direct the non-equilibrium growth of anisotropic colloidal single crystals, producing hexagonal prism microcrystals with tailored facet terminations that influence optical scattering and field enhancement. High-resolution liquid-phase electron microscopy has further revealed how thermal capillary waves and facet-dependent interfacial stiffness shape the surface morphology of supracrystals, providing quantitative insight into facet-selective growth energies and enabling predictive design of optical superstructures.

Nanoparticle Superlattice Assembly and Optical Properties publication trend

The graph below shows the total number of articles in nanoparticle superlattice assembly and optical properties across all publications each year (not limited to Nature Index journals).

Technical terms

Superlattice: A periodic array of nanoparticles forming a crystalline structure with well-defined symmetry and spacing.

Plasmon resonance: Collective oscillation of conduction electrons in metallic nanoparticles, leading to strong light absorption and scattering at specific wavelengths.

Mie resonance: Optical resonances arising from dielectric or metallic particles when their size is comparable to the wavelength of incident light, producing multipolar scattering peaks.

Metamaterial: An engineered composite medium whose effective permittivity and permeability are defined by subwavelength structural units rather than only by its chemical composition.

Interparticle spacing: The centre-to-centre distance between adjacent nanoparticles, which critically determines coupling strength and emergent optical properties.

Colloidal self-assembly: A bottom-up process in which suspended nanoparticles organise into ordered structures driven by interparticle forces and external stimuli.

References

1. Colloidal metasurfaces displaying near-ideal and tunable light absorbance in the infrared. Nature Communications (2015).
2. Non-equilibrium anisotropic colloidal single crystal growth with DNA. Nature Communications (2018).
3. Plasmon nanoparticle superlattices as optical-frequency magnetic metamaterials.. Optics Express (2012).
4. Imaging how thermal capillary waves and anisotropic interfacial stiffness shape nanoparticle supracrystals. Nature Communications (2020).
5. Optical Mie Scattering by DNA-Assembled Three-Dimensional Gold Nanoparticle Superlattice Crystals. ACS Applied Optical Materials (2022).
6. Achieving Optical Refractive Index of 10‐Plus by Colloidal Self‐Assembly. Small (2024).