无铅KNN/rGO/PDMS柔性复合薄膜压电纳米发电机

Piezoelectric Nanogenerator Based on Lead-Free KNN/rGO/PDMS Flexible Composite Films

碱金属铌酸系(K,Na)NbO_(3)/聚二甲基硅氧烷(PDMS)无铅柔性复合薄膜压电纳米发电机因环境友好及良好的柔性引起了广泛关注。然而,复合材料的低介电常数限制了其应用。采用溶胶-凝胶技术合成K_(0.5)Na_(0.5)NbO_(3)(KNN)纳米粒子,通过旋涂工艺制备KNN/还原氧化石墨烯(rGO)/PDMS柔性复合薄膜,并采用多层封装工艺制备了KNN/rGO/PDMS压电纳米发电机。系统研究了rGO的掺杂量对复合薄膜压电纳米发电机的压电性能影响,当掺杂rGO的质量分数为1.5%时,KNN/rGO/PDMS柔性复合压电纳米发电机的输出电压达到最大值6.0 V,比未掺杂rGO的KNN/PDMS柔性复合压电纳米发电机输出电压提高了94%。KNN/rGO/PDMS柔性复合薄膜压电纳米发电机可为储能电容器(电容47μF)充电,并成功点亮商用红色发光二极管(LED),且该压电纳米发电机5000次敲击测试结果显示输出电压稳定。因此,该柔性复合薄膜压电纳米发电机有望在柔性自供电可穿戴设备和电子皮肤等领域得到广泛应用。

Lead-free flexible composite film piezoelectric nanogenerators based on alkali metal niobite(K,Na)NbO_(3)/polydimethylsiloxane(PDMS)attract extensive attention due to their environmental friendliness and excellent flexibility.However,low dielectric constant of the composite limits its applications.K_(0.5)Na_(0.5)NbO_(3)(KNN)nanoparticles were synthesized by the sol-gel technique,and KNN/reduced graphene oxide(rGO)/PDMS flexible composite film was prepared with the spin coating process,and then KNN/rGO/PDMS piezoelectric nanogenerators were fabricated by multilayered packaging process.The effect of doping amount of rGO on piezoelectric properties of the composite film piezoelectric nanogenerator was systematically studied.When the mass fraction of the doped rGO is 1.5%,the maximum output voltage of the KNN/rGO/PDMS flexible composite piezoelectric nanogenerator is 6.0 V,which is enhanced 94%compared with the KNN/PDMS flexible composite piezoelectric nanogenerator without doping rGO.The KNN/rGO/PDMS flexible composite film piezoelectric nanogenerator can charge energy storage capacitor(capacitance of 47μF),and can successfully light up a commercial red light-emitting diode(LED).The results of the tapping test for 5000 times show that the output voltage of the prepared piezoelectric nanogenerator is stable.Therefore,the flexible composite film piezoelectric nanogenerator is expected to be widely used in flexible self-powered wearable devices,electronic skin and other fields.