The State of the Art: Application of Green Technology in Sustainable Pavement

Table 1

Features of piezoelectric materials.

Material type	Example material	Chemical composition	Advantage	Disadvantage	Reference
Inorganic piezoelectric material	Piezoelectric ceramics	Barium titanate (BaTiO3)	Wide usage and high structural stiffness	Unstable dielectric constant	[20]
		PZT materials (PbZrO3–PbTiO3)	High electromechanical coupling factor and high efficiency of electromechanical conversion	Brittle and fragile	[18]
	Crystalline materials	Lead titanate (PbTiO3)	High ratio of k33 to kp with a high kt and obtainable from the nature as mineral macedonite	Toxic	[21, 22]
Piezoelectric polymer	Polyvinylidene fluoride (PVDF)	-(CH2-CF2)n-	High mechanical strength and toughness	Low electromechanical coupling factor	[23]
Composite piezoelectric material	Piezoelectric fiber/polymer composites	NA	Low energy density, low acoustic impedance, soft, and high flexibility	Complicate construction process	[24, 25]

Note. NA: not available.