The formation and stability of self-assembled monolayers of octadecylphosphonic acid on titania
نویسندگان
چکیده
Octadecylphosphonic acid (OPA) forms monolayers on amorphous smooth titania surfaces. The OPA was deposited by immersion in tetrahydrofuran solutions. The process takes place rapidly at 2× 10−4 M OPA, evidence of which is an advancing water contact angle of approx. 100◦ after 10 s of immersion. The advancing water contact angle plateaus at 110± 2◦ after several hours. At lower concentrations (2× 10−6 and 2× 10−8 M OPA), only partial coverage of OPA on titania films is achieved. OPA self-assembled monolayers (SAMs) are resistant to exposure to common solvents. Water wettability is a function of the molecular volume o c
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