Tunable Nanoparticle Stripe Patterns at Inclined Surfaces

Suman Bhattacharjee; Sanjoy Khawas; Sunita Srivastava

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arXiv · 2601.20165

Tunable Nanoparticle Stripe Patterns at Inclined Surfaces

Suman Bhattacharjee·Sanjoy Khawas·Sunita Srivastava

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Abstract

Periodic assemblies of nanoparticles are central to surface patterning, with applications in biosensing, energy conversion, and nanofabrication. Evaporation of colloidal droplets on substrates provides a simple yet effective route to achieve such assemblies. This work reports the first experimental demonstration of patterns formed through stick-slip dynamics of the three-phase contact line during evaporation of gold nanoparticle suspensions on inclined substrates. Variation in nanoparticle concentration and substrate inclination alter the balance of interfacial and gravitational forces, producing multiple stick-slip events that generate periodic stripes. Stripe density exhibits a sinusoidal dependence on inclination angle, while inter-stripe spacing remains nearly invariant. Independent control over inter-stripe spacing is achieved through adjustment of nanoparticle or surfactant concentration. These results highlight the complex interplay of gravitational and interfacial forces in directing periodic nanoparticle assembly and establish a versatile, programmable framework for surface patterning with tunable nano/microscale dimensions.

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Suman Bhattacharjee, Sanjoy Khawas, Sunita Srivastava. 2026-01-28. Tunable Nanoparticle Stripe Patterns at Inclined Surfaces. https://arxiv.org/abs/2601.20165

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