{"id":{"repo_id":"aalto","oai_identifier":"oai:aaltodoc.aalto.fi:123456789/118458"},"canonical_url":"https://search.dev.ndltd.org/etd/aalto/oai:aaltodoc.aalto.fi:123456789/118458","repository":{"repo_id":"aalto","name":"Aalto University","base_url":"https://aaltodoc.aalto.fi/server/oai/request"},"display":{"title":"Superhydrophobic metrology and applications","abstract":"Superhydrophobic surfaces repel water and exhibit useful properties like self-cleaning, anti-fogging, anti-icing, and anti-fouling. Current characterization techniques have trouble grading the superhydrophobicity of samples due to limits in force and optical resolution. Thus, more suitable measurement techniques are needed to grade superhydrophobic surfaces. The current standard method, contact angle goniometer (CAG), is compared to two force-based measurement techniques: oscillating droplet tribometer (ODT) and micropipette force sensor (MFS). In addition, the properties of superhydrophobic surfaces are explored for lubrication. Publication I compares the sensitivity of the MFS and CAG on measuring superhydrophobic surfaces. In this publication, MFS measures the contact angle hysteresis force and CAG measures the contact angles of superhydrophobic surfaces. For superhydrophobic surfaces, the MFS can easily distinguish even slight differences between the samples, while the CAG cannot differentiate the samples from each other. Publication II studies the sensitivity of the ODT and CAG on measuring superhydrophobic surfaces. In this publication, the viscous and contact angle hysteresis force is measured using ODT and the contact angles with CAG. For the measured superhydrophobic surfaces, the ODT can differentiate all the samples and even find slight differences in heat treated nanostructured copper samples, while the CAG cannot distinguish the samples from each other. Publication III uses the MFS in an oscillating mode, which is based on the model of the ODT. In this publication, levitating carbonated water and MilliQ water are used to study the viscous losses in the air layer between the droplet and the surface in superhydrophobic surfaces. A mathematical model is constructed to explain the losses in the system, and it is validated using experimental data. Publication IV explores the lubrication properties of a the superhydrophobic surface. A slippery air-water bilayer forms between superhydrophobic surface and a water layer. This bilayer is used to lower dissipation forces between two solids. These dissipation forces are measured using oscillating tribometer and tilted plane. Extreme level of lubrication is demonstrated at low velocities (v<1 m/s) and pressures (50 Pa) using this system with friction coefficients at the order of 0.001, which is on par with the state-of-the-art lubrication methods. This thesis demonstrates the accuracy of ODT and MFS for characterizing superhydrophobic surfaces and the limited suitability of CAG for characterizing superhydrophobic surfaces. The need for these type of measurement devices will increase, as more superhydrophobic surfaces and application enter the market. These accurate measurement devices will be critical for utilizing and commercializing the useful properties of superhydrophobic surfaces.","abstract_html":"Superhydrophobic surfaces repel water and exhibit useful properties like self-cleaning, anti-fogging, anti-icing, and anti-fouling. Current characterization techniques have trouble grading the superhydrophobicity of samples due to limits in force and optical resolution. Thus, more suitable measurement techniques are needed to grade superhydrophobic surfaces. The current standard method, contact angle goniometer (CAG), is compared to two force-based measurement techniques: oscillating droplet tribometer (ODT) and micropipette force sensor (MFS). In addition, the properties of superhydrophobic surfaces are explored for lubrication. Publication I compares the sensitivity of the MFS and CAG on measuring superhydrophobic surfaces. In this publication, MFS measures the contact angle hysteresis force and CAG measures the contact angles of superhydrophobic surfaces. For superhydrophobic surfaces, the MFS can easily distinguish even slight differences between the samples, while the CAG cannot differentiate the samples from each other. Publication II studies the sensitivity of the ODT and CAG on measuring superhydrophobic surfaces. In this publication, the viscous and contact angle hysteresis force is measured using ODT and the contact angles with CAG. For the measured superhydrophobic surfaces, the ODT can differentiate all the samples and even find slight differences in heat treated nanostructured copper samples, while the CAG cannot distinguish the samples from each other. Publication III uses the MFS in an oscillating mode, which is based on the model of the ODT. In this publication, levitating carbonated water and MilliQ water are used to study the viscous losses in the air layer between the droplet and the surface in superhydrophobic surfaces. A mathematical model is constructed to explain the losses in the system, and it is validated using experimental data. Publication IV explores the lubrication properties of a the superhydrophobic surface. A slippery air-water bilayer forms between superhydrophobic surface and a water layer. This bilayer is used to lower dissipation forces between two solids. These dissipation forces are measured using oscillating tribometer and tilted plane. Extreme level of lubrication is demonstrated at low velocities (v&lt;1 m/s) and pressures (50 Pa) using this system with friction coefficients at the order of 0.001, which is on par with the state-of-the-art lubrication methods. This thesis demonstrates the accuracy of ODT and MFS for characterizing superhydrophobic surfaces and the limited suitability of CAG for characterizing superhydrophobic surfaces. The need for these type of measurement devices will increase, as more superhydrophobic surfaces and application enter the market. These accurate measurement devices will be critical for utilizing and commercializing the useful properties of superhydrophobic surfaces.","abstract_has_math":false,"creators":["Nurmi, Heikki A."],"institution":"Aalto University","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":"Teknillisen fysiikan laitos","school":null,"contributors":["Aalto-yliopisto","Aalto University"],"advisors":["Jokinen, Ville, Dr., Aalto University, Department of Chemistry and Materials Science, Finland","Ras, Robin, Prof., Aalto University, Department of Applied Physics, Finland"],"committee_chairs":[],"committee_members":[],"year":2022,"date_issued":"2022","date_published":"2022","updated_at":"2026-08-21T22:21:56Z","subjects":[],"languages":["en"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://aaltodoc.aalto.fi/handle/123456789/118458","outbound_label":"Repository record","outbound_source":"dc:identifier.uri"},"source_record":{"url":"https://aaltodoc.aalto.fi/server/oai/request?verb=GetRecord&metadataPrefix=dim&identifier=oai%3Aaaltodoc.aalto.fi%3A123456789%2F118458","prefix":"dim"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Aalto-yliopisto","Aalto University"]},{"key":"dc:contributor.advisor","label":"Advisor","values":["Jokinen, Ville, Dr., Aalto University, Department of Chemistry and Materials Science, Finland"]},{"key":"dc:contributor.department","label":"Department","values":["Teknillisen fysiikan laitos","Department of Applied Physics"]},{"key":"dc:contributor.supervisor","label":"Supervisor","values":["Ras, Robin, Prof., Aalto University, Department of Applied Physics, Finland"]},{"key":"dc:creator","label":"Author","values":["Nurmi, Heikki A."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2022-12-21T10:00:12Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2022-12-21T10:00:12Z"]},{"key":"dc:date.issued","label":"Date","values":["2022"]},{"key":"dc:publisher","label":"Institution","values":["Aalto University","Aalto-yliopisto"]},{"key":"dc:type","label":"Dc Type","values":["G5 Artikkeliväitöskirja"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["text"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://aaltodoc.aalto.fi/handle/123456789/118458"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Superhydrophobic surfaces repel water and exhibit useful properties like self-cleaning, anti-fogging, anti-icing, and anti-fouling. Current characterization techniques have trouble grading the superhydrophobicity of samples due to limits in force and optical resolution. Thus, more suitable measurement techniques are needed to grade superhydrophobic surfaces. The current standard method, contact angle goniometer (CAG), is compared to two force-based measurement techniques: oscillating droplet tribometer (ODT) and micropipette force sensor (MFS). In addition, the properties of superhydrophobic surfaces are explored for lubrication. Publication I compares the sensitivity of the MFS and CAG on measuring superhydrophobic surfaces. In this publication, MFS measures the contact angle hysteresis force and CAG measures the contact angles of superhydrophobic surfaces. For superhydrophobic surfaces, the MFS can easily distinguish even slight differences between the samples, while the CAG cannot differentiate the samples from each other. Publication II studies the sensitivity of the ODT and CAG on measuring superhydrophobic surfaces. In this publication, the viscous and contact angle hysteresis force is measured using ODT and the contact angles with CAG. For the measured superhydrophobic surfaces, the ODT can differentiate all the samples and even find slight differences in heat treated nanostructured copper samples, while the CAG cannot distinguish the samples from each other. Publication III uses the MFS in an oscillating mode, which is based on the model of the ODT. In this publication, levitating carbonated water and MilliQ water are used to study the viscous losses in the air layer between the droplet and the surface in superhydrophobic surfaces. A mathematical model is constructed to explain the losses in the system, and it is validated using experimental data. Publication IV explores the lubrication properties of a the superhydrophobic surface. A slippery air-water bilayer forms between superhydrophobic surface and a water layer. This bilayer is used to lower dissipation forces between two solids. These dissipation forces are measured using oscillating tribometer and tilted plane. Extreme level of lubrication is demonstrated at low velocities (v<1 m/s) and pressures (50 Pa) using this system with friction coefficients at the order of 0.001, which is on par with the state-of-the-art lubrication methods. This thesis demonstrates the accuracy of ODT and MFS for characterizing superhydrophobic surfaces and the limited suitability of CAG for characterizing superhydrophobic surfaces. The need for these type of measurement devices will increase, as more superhydrophobic surfaces and application enter the market. These accurate measurement devices will be critical for utilizing and commercializing the useful properties of superhydrophobic surfaces.","Superhydrofobiset pinnat hylkivät vettä ja niillä on hyödyllisiä ominaisuuksia kuten itsepuhdistuminen, huurtumattomuus, jäänesto ja huonosti likaantuminen. Tämänhetkisillä mittausmenetelmillä on vaikeuksia erotella superhydrofobisia pintoja rajallisen voima ja optisen resoluution takia. Täten sopivampia mittausmenetelmiä tarvitaan superhydrofobisten pintojen erotteluun. Nykyistä standardi menetelmää, kontaktikulmamittaria, verrataan kahteen voimaan perustuvaan menetelmään pisaraheilurikitkamittariin ja mikropipettivoimasensoriin. Tämän lisäksi tutkittiin superhydrofobisten pintojen soveltuvuutta voiteluun. Julkaisu I vertailee mikropipettivoimasensorin ja kontaktikulmamittarin mittausherkkyyttä superhydrofobisilla pinnoilla. Tässä julkaisussa mikropipettivoimasensori mittaa kontaktikulmahystereesivoiman ja kontaktikulmamittari pisaran kontakti kulmat. Mikropipettivoimasensori pystyy helposti erottelemaan superhydrofobisia pintoja toisistaan, kun taas kontaktikulmamittarilla ei pystytty erottelemaan eri superhydrofobisia näytteitä. Julkaisussa II pisaraheilurikitkamittarin mittausherkkyyttä superhydrofobisilla pinnoilla verrataan kontaktikulmamittarin herkkyyteen. Tässä julkaisussa pisaraheilurikitkamittarilla mitataan viskoosi ja kontaktikulmahystereesi voimien suuruudet ja kontaktikulmamittarilla kontaktikulma hystereesi. Pisaraheilurikitkamittari pystyi erottamaan kaikki superhydrofobiset pinnat toisistaan ja löytämään pieniä eroja lämpökäsitellystä nanorakenteisestä kupari näytteestä, kun taas kontaktikulmamittarilla ei pystytty löytämään eroja näytteiden välillä. Julkaisu III tutkii mikropipettivoimasensorin oskilloivaa versiota, jonka perustuu pisaraheilurikitkamittarin mallinnukseen. Julkaisussa käytetään hiilihapotettua vettä ja MilliQ-vettä viskoosien häviöiden tutkimiseen pisaran ja superhydrofobisen pinnan välisessä ilmakerroksessa. Julkaisussa rakennetaan viskooseja häviöitä kuvaava malli, joka todennetaan kokeellisilla mittauksilla. Julkaisu IV tutkii superhydrofobisten pintojen käyttöä voiteluun. Liukas ilmavesikaksoiskerros muodostuu superhydrofobisen pinnan ja veden väliin. Kaksoiskerrosta käytetään vähentämään kahden kiinteän kappaleen välillä olevia häviövoimia. Häviövoimat mitataan pisaraheilurikitkamittarilla ja kaltevalla pinnalla. Mittauksissa saavutetaan erittäin hyvä voitelu matalilla nopeuksilla (v<1 m/s) ja paineella (50 Pa) kitakertoimen ollessa suuruusluokaltaan 0.001, joka on vastaavalla tasolla parhaimpien voitelumenetelmien kanssa. Väitöskirja esittelee pisaraheilurikitkamittarin ja mikropipettivoimasensorin superhydrofobisten pintojen mittaustarkkuutta ja kontaktikulmamittarin rajallista soveltuvuutta superhydrofobisten pintojen erotteluun. Tarve tällaisille mittalaitteille tulee kasvamaan, kun uusia superhydrofobisia pintoja ja sovelluksia tulee markkinoille lisää. Tarkat mittaukset ovat kriittisiä, jotta superhydrofobisten pintojen hyödyllisiä ominaisuuksia saadaan hyödynnettyä ja kaupallistettua."]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Superhydrophobic metrology and applications","Superhydrofobian metrologia ja käyttökohteet"]}]}],"canonical_facts":{"dc:contributor":["Aalto-yliopisto","Aalto University"],"dc:contributor.advisor":["Jokinen, Ville, Dr., Aalto University, Department of Chemistry and Materials Science, Finland"],"dc:contributor.department":["Teknillisen fysiikan laitos","Department of Applied Physics"],"dc:contributor.supervisor":["Ras, Robin, Prof., Aalto University, Department of Applied Physics, Finland"],"dc:creator":["Nurmi, Heikki A."],"dc:date.accessioned":["2022-12-21T10:00:12Z"],"dc:date.available":["2022-12-21T10:00:12Z"],"dc:date.issued":["2022"],"dc:description.abstract":["Superhydrophobic surfaces repel water and exhibit useful properties like self-cleaning, anti-fogging, anti-icing, and anti-fouling. Current characterization techniques have trouble grading the superhydrophobicity of samples due to limits in force and optical resolution. Thus, more suitable measurement techniques are needed to grade superhydrophobic surfaces. The current standard method, contact angle goniometer (CAG), is compared to two force-based measurement techniques: oscillating droplet tribometer (ODT) and micropipette force sensor (MFS). In addition, the properties of superhydrophobic surfaces are explored for lubrication. Publication I compares the sensitivity of the MFS and CAG on measuring superhydrophobic surfaces. In this publication, MFS measures the contact angle hysteresis force and CAG measures the contact angles of superhydrophobic surfaces. For superhydrophobic surfaces, the MFS can easily distinguish even slight differences between the samples, while the CAG cannot differentiate the samples from each other. Publication II studies the sensitivity of the ODT and CAG on measuring superhydrophobic surfaces. In this publication, the viscous and contact angle hysteresis force is measured using ODT and the contact angles with CAG. For the measured superhydrophobic surfaces, the ODT can differentiate all the samples and even find slight differences in heat treated nanostructured copper samples, while the CAG cannot distinguish the samples from each other. Publication III uses the MFS in an oscillating mode, which is based on the model of the ODT. In this publication, levitating carbonated water and MilliQ water are used to study the viscous losses in the air layer between the droplet and the surface in superhydrophobic surfaces. A mathematical model is constructed to explain the losses in the system, and it is validated using experimental data. Publication IV explores the lubrication properties of a the superhydrophobic surface. A slippery air-water bilayer forms between superhydrophobic surface and a water layer. This bilayer is used to lower dissipation forces between two solids. These dissipation forces are measured using oscillating tribometer and tilted plane. Extreme level of lubrication is demonstrated at low velocities (v<1 m/s) and pressures (50 Pa) using this system with friction coefficients at the order of 0.001, which is on par with the state-of-the-art lubrication methods. This thesis demonstrates the accuracy of ODT and MFS for characterizing superhydrophobic surfaces and the limited suitability of CAG for characterizing superhydrophobic surfaces. The need for these type of measurement devices will increase, as more superhydrophobic surfaces and application enter the market. These accurate measurement devices will be critical for utilizing and commercializing the useful properties of superhydrophobic surfaces.","Superhydrofobiset pinnat hylkivät vettä ja niillä on hyödyllisiä ominaisuuksia kuten itsepuhdistuminen, huurtumattomuus, jäänesto ja huonosti likaantuminen. Tämänhetkisillä mittausmenetelmillä on vaikeuksia erotella superhydrofobisia pintoja rajallisen voima ja optisen resoluution takia. Täten sopivampia mittausmenetelmiä tarvitaan superhydrofobisten pintojen erotteluun. Nykyistä standardi menetelmää, kontaktikulmamittaria, verrataan kahteen voimaan perustuvaan menetelmään pisaraheilurikitkamittariin ja mikropipettivoimasensoriin. Tämän lisäksi tutkittiin superhydrofobisten pintojen soveltuvuutta voiteluun. Julkaisu I vertailee mikropipettivoimasensorin ja kontaktikulmamittarin mittausherkkyyttä superhydrofobisilla pinnoilla. Tässä julkaisussa mikropipettivoimasensori mittaa kontaktikulmahystereesivoiman ja kontaktikulmamittari pisaran kontakti kulmat. Mikropipettivoimasensori pystyy helposti erottelemaan superhydrofobisia pintoja toisistaan, kun taas kontaktikulmamittarilla ei pystytty erottelemaan eri superhydrofobisia näytteitä. Julkaisussa II pisaraheilurikitkamittarin mittausherkkyyttä superhydrofobisilla pinnoilla verrataan kontaktikulmamittarin herkkyyteen. Tässä julkaisussa pisaraheilurikitkamittarilla mitataan viskoosi ja kontaktikulmahystereesi voimien suuruudet ja kontaktikulmamittarilla kontaktikulma hystereesi. Pisaraheilurikitkamittari pystyi erottamaan kaikki superhydrofobiset pinnat toisistaan ja löytämään pieniä eroja lämpökäsitellystä nanorakenteisestä kupari näytteestä, kun taas kontaktikulmamittarilla ei pystytty löytämään eroja näytteiden välillä. Julkaisu III tutkii mikropipettivoimasensorin oskilloivaa versiota, jonka perustuu pisaraheilurikitkamittarin mallinnukseen. Julkaisussa käytetään hiilihapotettua vettä ja MilliQ-vettä viskoosien häviöiden tutkimiseen pisaran ja superhydrofobisen pinnan välisessä ilmakerroksessa. Julkaisussa rakennetaan viskooseja häviöitä kuvaava malli, joka todennetaan kokeellisilla mittauksilla. Julkaisu IV tutkii superhydrofobisten pintojen käyttöä voiteluun. Liukas ilmavesikaksoiskerros muodostuu superhydrofobisen pinnan ja veden väliin. Kaksoiskerrosta käytetään vähentämään kahden kiinteän kappaleen välillä olevia häviövoimia. Häviövoimat mitataan pisaraheilurikitkamittarilla ja kaltevalla pinnalla. Mittauksissa saavutetaan erittäin hyvä voitelu matalilla nopeuksilla (v<1 m/s) ja paineella (50 Pa) kitakertoimen ollessa suuruusluokaltaan 0.001, joka on vastaavalla tasolla parhaimpien voitelumenetelmien kanssa. Väitöskirja esittelee pisaraheilurikitkamittarin ja mikropipettivoimasensorin superhydrofobisten pintojen mittaustarkkuutta ja kontaktikulmamittarin rajallista soveltuvuutta superhydrofobisten pintojen erotteluun. Tarve tällaisille mittalaitteille tulee kasvamaan, kun uusia superhydrofobisia pintoja ja sovelluksia tulee markkinoille lisää. Tarkat mittaukset ovat kriittisiä, jotta superhydrofobisten pintojen hyödyllisiä ominaisuuksia saadaan hyödynnettyä ja kaupallistettua."],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["https://aaltodoc.aalto.fi/handle/123456789/118458"],"dc:language.iso":["en"],"dc:publisher":["Aalto University","Aalto-yliopisto"],"dc:title":["Superhydrophobic metrology and applications","Superhydrofobian metrologia ja käyttökohteet"],"dc:type":["G5 Artikkeliväitöskirja"],"dc:type.dcmitype":["text"]},"updated_at":"2026-08-21T22:21:56Z"}