fe_nd_b cross section chemical_compound FrictionForce TiO2 ForceMapping Growth Alkane Ferroelectric sputter AM_KPFM BiFeO3 Laser CntFilm LiNbO3 DNA SFAs Multiferroic_materials UnivCollegeLondon India Phenanthrene ConductiveAFM VinylAlcohol NCM\ ScanningTunnelingMicroscopy alkanes Pore Sapphire conductive Styrene SAM Beads ImideMonomer Mapping Blend