title: Bioinspired Polymeric Photonic Crystals for High Cycling pH-Sensing Performance.
abstract: Artificial photonic crystals (PCs) have been extensively studied to improve the sensing performance of poly(acrylic acid) (PAAc), as it can transform the PAAc volume change into optical signal which is easier to read. Nevertheless, these PCs are limited by the monostructure. We herein developed new photonic crystals (PCs) by coating acrylic acid and acrylamide (AAm) via in situ copolymerization onto Papilio paris wings having hierarchical, lamellar structure. Our PCs exhibited high performance of color tunability to environmental pH, as detected by reflectance spectra and visual observation. The introduction of AAm into the system created covalent bonding which robustly bridged the polymer with the wings, leading to an accurate yet broad variation of reflection wavelength to gauge environmental pH. The reflection wavelength can be tailored by the refractive index of the lamellar interspacing due to the swelling/deswelling of the polymer. The mechanism is not only supported by experimenta but proved by finite-difference time-domain simulation. Moreover, It is worth noting that the covalent bonding has provided the PCs-based pH sensor with high cycling performance, implying great potential in practical applications. The simple fabrication process is applicable to the development of a wide variety of stimuli-responsive PCs taking advantage of other polymers.
authors.affiliation: State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University , Shanghai 200240, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Fei
authors.affiliation: State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University , Shanghai 200240, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Lu
authors.affiliation: School of Engineering, University of South Australia , Mawson Lakes, SA 5095, Australia.
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.affiliation: College of Electronic Science and Technology and Guangdong Provincial Key Laboratory of Optoelectronic Micro/Nano Optomechatronics Engineering, Shenzhen University , Shenzhen 518060, China.
authors.forename: Wanlin
authors.initials: W
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University , Shanghai 200240, China.
authors.forename: Shenmin
authors.initials: S
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University , Shanghai 200240, China.
authors.forename: Di
authors.initials: D
authors.lastname: Zhang
keywords: biotemplate; hydrogel; pH response; photonic crystals; sensor