Piezoelectric Hexacontane Molybdenum_disulfide PS_PVAC LithiumNiobate Blend WS2 BiasMode SAM vertical_PFM CBD Crystal CarbonNanotube Graphene NUS_NNI_Nanocore AlkaneFilm UnivCollegeLondon Polarization NUS phase_change Formamidinium_lead_iodide ImideMonomer HBN Lateral_Force_Microscopy AM-KPFM LaAlO3 SolarCell Piranha LateralPFM MetalCompound Bio DIWafer PolyvinylAcetate norganic KPFM