Current Status and Prospects of Additive Manufacturing of Flexible Piezoelectric Materials

doi:10.15541/jim20240050

Abstract

Abstract:

As a kind of important functional material, flexible piezoelectric materials can realize the effective conversion between mechanical energy and electrical energy, with the advantages of good toughness, high plasticity and light weight. Therefore, they can be attached to the human body to obtain human or environment information in real time, which is widely used in the fields of motion detection, health monitoring, and human-computer interaction. Due to high requirements of various three-dimensional (3D) structures of the flexible piezoelectric materials, additive manufacturing has been extensively utilized to fabricate different kinds of piezoelectric materials. This technology is expected to break the bottleneck of traditional processing of piezoelectric material by improving the structural design freedom and the performance of flexible piezoelectric materials, and provides enormous potential and opportunities for the application of flexible piezoelectric materials. Based on the introduction of the classification and features of flexible piezoelectric materials, this paper explained the main additive manufacturing technologies, including fused deposition modeling, direct ink writing, selective laser sintering, electric-assisted direct writing, stereolithography, and inkjet printing that commonly used in processing these materials. Then, various structural designs, such as multi-layer structure, porous structure, and interdigital structure for the flexible piezoelectric materials produced by different additive manufacturing approaches were reviewed. Moreover, the applications of additive manufactured flexible piezoelectric materials in energy harvesting, piezoelectric sensing, human-computer interaction, and bioengineering were introduced. Finally, the challenges faced by additive manufacturing on processing flexible piezoelectric materials and the development trends in the future were summarized and prospected.

Key words: flexible piezoelectric material, additive manufacturing, ceramic, structure, functional application, review

CLC Number:

TB332

WEI Xiangxia, ZHANG Xiaofei, XU Kailong, CHEN Zhangwei. Current Status and Prospects of Additive Manufacturing of Flexible Piezoelectric Materials[J]. Journal of Inorganic Materials, 2024, 39(9): 965-978.

Figures/Tables 11

Fig. 1 Overview of additive manufacturing of flexible piezoelectric materials (a) Amount of published papers (data from Web of Science); (b) Additive manufacturing approaches, structural design and applications of flexible piezoelectric materials

Fig. 2 Summary of classification of piezoelectric materials PVDF: Polyvinylidene fluoride; PVDF-TrFE: Polyvinylidene fluoride-trifluoroethylene; PZT: Lead zirconate titanate; PMN-PT: Lead magnesium niobate-lead titanate; KNN: Potassium sodium niobate; PDMS: Polydimethylsiloxane

Fig. 3 Schematic diagrams of additive manufacturing processes (a) Fused deposition modeling[37]; (b) Direct ink writing[54] ; (c) Selective laser sintering[31]; (d) Electric-assisted direct writing [49]; (e) Stereolithography[50]; (f) Inkjet printing[53]

Fig. 4 Schematic diagrams of multi-layer structures of flexible piezoelectric materials (a) PVDF-TrFE composite multi-layer structures[55]; (b) Curved multi-layer piezoelectric structures[57]; (c) Rugby structures[58]

Fig. 5 Schematic diagrams of porous structures of flexible piezoelectric materials (a) PVDF-TrFE/BaTiO3 porous structures[60]; (b) CNF/PDMS porous structures[61]; (c) Grid structures[62]

Fig. 6 Schematic diagrams of interdigital structures of flexible piezoelectric materials (a) Alternately tilted interdigital structures[63]; (b) Pt/Ti conductive interdigital structures[64]; (c) Origami structures[65]

Table 1 Performance comparison of piezoelectric energy harvesters manufactured by 3D printing technology

Material	Filler	3D printing method	Fraction (β phase)/%	d₃₃(d₃₁)/(pC·N^-1)	Output voltage	Output current	Ref.
PVDF	BT (10%)	DIW	78	-	4 V	-	[43]
PVDF	TrFE (30%)	DIW	75-80	-	298.3 mV	-	[67]
PVDF	GR (0.03%)	DIW	61.52	d₃₃=-8.7	0.35 V	-	[70]
PVDF	GR (1.5%)	SLS	-	-	16.97 V	274 nA	[71]
PVDF	BT/Ag	SLS	-	-	10 V	142 nA	[72]
PVDF	BT/Carbon	SLS	92.2	-	5.7 V	79.8 nA	[73]
PVDF	BT (30%)	FDM	84.9	d₃₃=4.2	11.5 V	220 nA	[35]
PVDF	IL	FDM	93.3	-	8.69 V	90.8 nA	[74]
PVDF	TPPC (5%)	FDM	83.8	d₃₃=11.85	6.62 V	108.15 nA/cm²	[67]
PVDF	BT₂	FDM	95.9	-	10.9 V	126.9 nA	[75]
PVDF	IL (2%)	FDM	90	-	6 V	83 nA	[76]
PVDF	IL (15%)	FDM	97.4	-	8.2 V	300 nA	[77]
PVDF	No fillers	FDM	56.83	d₃₁=0.048	-	0.106 nA	[78]
PDMS	MWCNTs	DIW	-	d₃₃=1070	550 mV	-	[39]
PDMS	BaTiO₃	DIW	-	-	80 V	25 mA	[33]
PDMS	PNN-PZT	DIW	-	d₃₃=24	5 V	0.1 μA	[62]
PDMS	BT (80%)	DIW	-	-	45 V	2.7 μA	[40]
PVDF	TrFE	IJP	-	-	3.6 V	2.3μA	[53]

Fig. 7 Application of 3D-printed flexible piezoelectric materials in energy harvesting (a) Energy collection and illumination of LED lights by pressing with fingers[67]; (b) Application of M12N insoles[68]; (c) Piezoelectric energy harvester installed on wearable electronic devices[69]; (d) Road energy harvester[46]

Fig. 8 Application of 3D-printed flexible piezoelectric materials in piezoelectric sensing (a) Piezoelectric sensors incorporated into insoles to adapt to human movements[76]; (b) Self-powered traffic monitoring system based on PVDF[84]; (c) Schematic diagrams of wireless self-sensing boxing gloves[85]

Fig. 9 Application of 3D-printed flexible piezoelectric materials in human-computer interaction (a) Movement of the fingers translates into a change in voltage[90]; (b) Self-powered smart bracelet[91]; (c) Movements of robotic hands controlled by the movements of human hands[92]

Fig. 10 Application of 3D-printed flexible piezoelectric materials in bioengineering (a) Schematic diagram of electronic skin[93]; (b) Tissue engineering scaffold composed of PVDF/PCL[94]; (c) Piezoelectric hydrogel scaffold fabricated by 3D printing technology[95]

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