Strong Biomimetic Immobilization of Pt-Particle Catalyst on ABS Substrate Using Polydopamine and Its Application for Contact-Lens Cleaning with H₂O₂

• Main Authors: Yuji Ohkubo, Tomonori Aoki, Daisuke Kaibara, Satoshi Seino, Osamu Mori, Rie Sasaki, Katsuyoshi Endo, Kazuya Yamamura
• Format: Article
• Language: English
• Published: MDPI AG 2020-01-01
• Series: Nanomaterials
• Subjects: catalytic durability; polydopamine (pda); strong adhesion; supported catalyst; h₂o₂ decomposition
• Online Access: https://www.mdpi.com/2079-4991/10/1/114

Polydopamine (PDA)—a known adhesive coating material—was used herein to strongly immobilize a Pt-particle catalyst on an acrylonitrile−butadiene−styrene copolymer (ABS) substrate. Previous studies have shown that the poor adhesion between Pt particles and ABS surfaces is a considerable problem, leading to low catalytic durability for H₂O₂ decomposition during contact-lens cleaning. First, the ABS substrate was coated with PDA, and the PDA film was evaluated by X-ray photoelectron spectroscopy. Second, Pt particles were immobilized on the PDA-coated ABS substrate (ABS-PDA) using the electron-beam irradiation reduction method. The Pt particles immobilized on ABS-PDA (Pt/ABS-PDA) were observed using a scanning electron microscope. The Pt-loading weight was measured by inductively coupled plasma atomic emission spectroscopy. Third, the catalytic activity of the Pt/ABS-PDA was evaluated as the residual H₂O₂ concentration after immersing it in a 35,000-ppm H₂O₂ solution (the target value was less than 100 ppm). The catalytic durability was evaluated as the residual H₂O₂ concentration after repeated use. The PDA coating drastically improved both the catalytic activity and durability because of the high Pt-loading weight and strong adhesion among Pt particles, PDA, and the ABS substrate. Plasma treatment prior to PDA coating further improved the catalytic durability.