svayasvaya

svayananotechnologies

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Scaled Nanoreactor Chemistry!

Svaya Nanotechnologies

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What’s Svaya up to?

Svaya Nanotechnologies

• Create a wide range of high-quality surface coatings at industrial scale (see slide 3)

• All based on MIT research on layer-by-layer assembly (explained in slide 4 & 5)

• Developed a method to load these films with metallic/semiconductor nanoparticles (see slide 6-7)

• Main application being developed: Ag-loaded antimicrobial films (slide 8)

• We’re now looking for new applications for this “nanoreactor” technique

svayasvayaPrecision and uniformity using simple processing

304/13/2023 Svaya Nanotechnologies

Biomimetic Structural Color Uniformity and Precision: reflectivity

Industrial Scale Processing

Using our methods we can create precise & uniform films over large scales. One example: reflective films based on alternating high- and low-refractive index layers.

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Our technology: Layer by Layer Assembly

Svaya Nanotechnologies

This is the technique we use to create all our coatings:• Gradually build up

multilayer nanoscale films

• Alternating deposition of +ve/-ve species (with rinsing steps)

• Water based solutions and chemistries

• Wide range of components

polymer polymer nanoparticlepolymer nanoparticle nanoparticle

50-2000 nm

svayasvaya

504/13/2023

High accuracy - “molecular beaker epitaxy”

Svaya Nanotechnologies

Ariga et al., Phys Chem Chem Phys (2007)

de Villiers et al., Advanced Drug Delivery Reviews 63:9, 701–715 (2011)

Robust charge reversal

Controlled Growth

Advantages of solution-based LbL methods• Linear growth of film thickness with layer number• No degradation in adsorption efficiency• Control comparable to vacuum-deposition methods like

molecular beam epitaxy (thus the nick-name), but at industrial scale

svayasvayaSome other examples of our LbL coatings

604/13/2023 Svaya Nanotechnologies

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Nanoreactor Chemistry – loading films with nanoparticles

Original lab-scale synthesis process

1. Coat substrate with poly(acrylic acid) PAA and poly(allylamine) PAH – by controlling pH, some fraction acid and amine groups will participate in ionic bonding, some fraction will remain neutral. PAA is a negatively charged polymer at these conditions and PAH is positively charged.

2. Soak film in solution containing metal salts and wait for ion exchange3. Expose film to reducing environment and generate metal nanoparticles. The

reaction groups in the films are regenerated, so can grow particles with repeated loading/reduction cycles.

Step 1 Step 2 Step 3

At Svaya, we’ve modified the process so we combine steps1 & 2 to make the process simpler and more scalable

COOH is regenerated!

svayasvayaControl of the synthesis – Silver, Gold, Copper, Iron, Lead, many more

process pH = 4.5 process pH = 3.5 process pH = 2.5

1x metal saltloading

5x metal saltloading

Bigger particles, more particles

svayasvayaExample: Deposition of silver loaded films

• Right after deposition, the coatings look transparent.• After a few hours they start to gain a purple tint, as Ag(+) is reduced to Ag(0)• Purple tint comes from nanoparticle absorbance of light

50 bilayers

25 bilayers

After heat treatment:metallic sheen

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Svaya NanotechnologiesCompany Confidential

1004/13/2023

Thank you! Excited to see your ideas for our

nanoreactor coatings