1 Introduction
2 Experimental
2.1 Preparation of MFe2O4 nanoparticles
2.2 Synthesis of PVDF/MFe2O4 nanocomposites
2.3 Characterization of nanoparticles
2.4 Optical properties investigation
2.5 Piezoelectric response
2.5.1 Digital storage oscilloscope
2.5.2 Piezo response force microscopy (PFM)
3 Results
3.1 Nanoparticles characterization
3.1.1 XRD
3.1.2 FTIR
3.1.3 HRTEM
3.1.4 FESEM
Co-ZnFe2O4 | Atomic % | Cu-ZnFe2O4 | Atomic % |
---|---|---|---|
Element | Element | ||
O K | 23.73 | O K | 22.35 |
FeK | 55.7 | FeK | 50.58 |
CoK | 13.7 | CuK | 11.16 |
ZnK | 6.87 | ZnK | 15.91 |
3.2 Optical properties
3.2.1 Reflectance and transmittance
3.2.2 Optical bandgap
Composite | Direct bandgap (Eg) (eV) |
---|---|
PVDF | 4 |
PVDF/(Co-ZnFe2O4) | 3 |
PVDF/(Cu-ZnFe2O4) | 2.4 |
PVDF filler | Band gap energy (eV) | References |
---|---|---|
ZnO | 5.2 | [34] |
Co1−xZnxFe2O4, x = 0.00, 0.05, 0.10, 0.15, and 0.20 | 1.93–1.98 | [35] |
CuFe2O4 | 2.7 | [36] |
Reduced graphene oxide (rGO) (0.5–3) wt% | 5–4.3 | [37] |
MgCl2 | 1.99 | [38] |
Carbon quantum dots (CQDs) (1–10) wt% | 5–2.96 | [39] |
PVDF/PVC/palladium NPs | 2.98 | [40] |
TiO2 | 3.2 | [41] |
PVDF/MWCNTs | 2 | [41] |
MWCNTs//TiO2 | 0.92 | [41] |
Ag-CuO/rGO (1–2.5) wt% | 2.5–1.19 | [42] |