1. Candle soot as a template for a transparent robust superamphiphobic coating
By: group 18

2. Graphical abstract
Scientist have created a superamphiphobic coating using candle soot and a silica layer
This gives the surface both hydrophobic and oleophobic properties
Thermal stability: coating was able to maintain properties until 400°C
Abrasion stability: coating maintained properties until layer was less than 2μm thick

3. Introduction
Superamphiphobic- meaning a surface is both superhydrophobic and superoleophobic
Hydrophobic- material is resistant to water
Oleophobic- material is resistant to oil
Example of a superamphiphobic coating:

4. Introduction
In industry, it is desirable to have hydrophobic/oleophobic surfaces. Because liquid has a low affinity for the surface, the liquid beads up, taking dirt and other particles with it.
This makes the material self-cleaning

5. Examples of Hydrophobic materials Examples of Oleophobic materials
Introduction
Examples of Hydrophobic materials
Examples of Oleophobic materials
Polyethylene
Polypropylene
Nylon 10,10
Low surface energy materials

6. Basic principles
When a liquid meets a surface, it meets at an angle where the liquid/vapor interface meets the solid
This is called the contact angle
Hydrophilic surfaces cause the water droplet to spread out, resulting in a smaller contact angle (0-90°)
Hydrophobic surfaces have contact angles >90°
Makin' contact. (2011, 03 04). Retrieved from

8. Basic principles
Roll-off angle: angle of a surface where a drop of liquid will start to move
Point where the force of gravity overcomes the force of surface tension
Bharat Bhushan, Yong Chae Jung, Natural and biomimetic artificial surfaces for superhydrophobicity, self-cleaning, low adhesion, and drag reduction, Progress in Materials Science, Volume 56, Issue 1, January 2011, Pages 1-108, ISSN , /j.pmatsci (

9. Work performed
Glass slide was held above a Paraffin candle and coated in its soot
Coating causes material to be superhydrophobic
However, the soot structure is fragile

10. Work Performed Soot was coated with a layer of silica
Using chemical vapor deposition of tetraethoxysilane and catalized by ammonia
This process makes the coating stronger

11. Work performed
The coated glass was then calcinated at 600˚C to make it transparent
Coated with semi-fluorinated silane by CVD

12. Work performed
Results show high contact angle with both water and organic liquids relative to the original surface

13. Work performed The coating began to break down:
Thermal stability test-
Fluorosilane began to break down at 400˚C- meaning coating lost its oleophobic properities
Silica network broke down at 1000˚C
Abrasion stability test-
Sand formed cavities in the coating, however, it maintained its superamphiphobic properties until the coating was less than 2µm thick
Schematic of sand abrasion test

14. Conclusion
This superamphiphobic coating is simple to make and effective against water, oil, and other hexanes
It is self cleaning because dirt and other solid particulate roll off with the liquid
It maintains its properties until 400°C
It is transparent- opening up a wide range of applications
Jiang, W., Hu, H., & Zhang , Y. (2013). Publications. Retrieved from

15. Assessment of the work Possible improvements:
The explanation of soot as the reason for the coating’s superamphiphobic properties is never thoroughly explained
The experiment lacks control over other possible influencing variables
The paper never explicitly explains what gives a material oleophobic properties

16. Assessment of the work Analysis
The paper presents a practical approach to making a superamphiphobic coating
From their test, the coating has a large number of useful applications ranging from goggles to large scale chemical production
Further research is required before the small scale process can be converted to a large scale commercialized product
The small scale lab set up isn’t necessarily practical on an industrial scale
Cost analysis would be necessary to ensure profitability

17. Further research Methods of cost efficient mass production
As we know, in industry, one of the most important considerations is cost.
If a company does not have a method to mass produce material at a low cost then they will not make a profit.
Research in this area would include searching for commercially available materials that also have the correct characteristics to create superamphiphobic properties

18. Further research
How to make Fluorosilane remain stabile at higher temps
As we have shown in our Work Performed, Fluorosilane began to break down at 400˚C- meaning coating lost its superamphibhobic properties
For our superamphiphobic material to more use,we need to increase to temperature range in which Fluorosilane remains stable.
Many reactions take place at temperatures higher than 400˚C. For these reactions, it is desirable for an superamphiphobic material to remain intact as a coating and not break down and become a possible impurity.

19. Further research Sand Abrasion
The Sand Abrasion Test showed that the superamphiphobic material is inevitably susceptible to wearing away.
Research should be performed to find ways to make superamphiphobic materials more resistant to wearing.
This is important because a more robust material leads to a longer lasting coating.

20. Further Research Roll off angle
There has been a lot of confirmed research in the area of Contact angle.
But, little to no information is given on Roll off Angle.
Research in this area would consist of experimentally finding correlations between Roll off Angle and specific qualities of materials.
End goal of statistical model for roll off angle.

21. References
Contact angle. (n.d.). Retrieved from
Deng, X., Mammen, L., Butt, H. & Vollmer, D. (2011, 12 01). Candle soot as a template for a transparent robust superamphiphobic coating. Science, 335, Retrieved from
Diversified Enterprises. (2009). Critical surface tension and contact angle with water for various polymers. Retrieved from
All uncited figures are taken from cited paper