Smart colloidal photonic crystal sensors

• Published in: Advances in colloid and interface science Vol. 324; p. 103089
• Main Authors: Hu, Yang, Tian, Ziqiang, Ma, Dekun, Qi, Chenze, Yang, Dongpeng, Huang, Shaoming
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.02.2024
• Subjects: Photonic crystals; Reflection wavelength; Refractive index; Sensors; Stimuli; Structural colors; Sensors; Structural colors; Reflection wavelength; Refractive index; Photonic crystals; Stimuli
• ISSN: 0001-8686; 1873-3727; 1873-3727
• DOI: 10.1016/j.cis.2024.103089

Smart colloidal photonic crystals (PCs) with stimuli-responsive periodic micro/nano-structures, photonic bandgaps, and structural colors have shown unique advantages (high sensitivity, visual readout, wireless characteristics, etc.) in sensing by outputting diverse structural colors and reflection signals. In this review, smart PC sensors are summarized according to their fabrications, structures, sensing mechanisms, and applications. The fabrications of colloidal PCs are mainly by self-assembling the well-defined nanoparticles into the periodical structure (supersaturation-, polymerization-, evaporation-, shear-, interaction-, and field-induced self-assembly process). Their structures can be divided into two groups: closely packed and non-closely packed nano-structures. The sensing mechanisms can be explained by Bragg's law, including the change in the effective refractive index, lattice constant, and the order degree. The sensing applications are detailly introduced according to the analytes of the target, including solvents, vapors, humidity, mechanical force, temperature, electrical field, magnetic field, pH, ions/molecules, and so on. Finally, the corresponding challenges and the future potential prospects of artificial smart colloidal PCs in the sensing field are discussed. Graphical abstract [Display omitted] •Colloidal photonic crystal (PC) sensors that can sensitively sense various physical/chemical stimuli by outputting diverse structural colors and reflective signals are reviewed.•The fabrications, structures, and sensing mechanisms of colloidal PC sensors are discussed.•The applications of colloidal PC sensors are summarized according to the classification of the analytes of the target.