StainlessSteel Calcium SingleLayer atomic_steps PtfeMembrane FAPbI3 DLaTGS Sidewall kelvin probe force microscopy FrictionalForce HexacontaneFilm LiNbO3 TemperatureControlledAFM PANI Cell SiliconOxide NTU LFM Collagen P3HT Monisha C36H74 PinpointPFM LiBattery Cobalt-dopedIronOxide biocompatible Fluoride optoelectronics MfmPhase fluoroalkane ContactMode ImideMonomer 2dMaterials CrAu semifluorinated_alkane