optoelectronics PDMS Carbon Tungsten_disulfide UnivMaryland Ucl SelfAssembly EPFL Magnetostrictive hetero_structure KelvinProbeForceMicroscopy FrictionalForce I-VSpectroscopy Microchannel Terrace Battery ULCA Titanate Defect KPFM mono_layer CuFoil Polyurethane PVAC DLaTGS alkanes mechanical property TCS Flake TemperatureControlledAFM Chrome Pvdf Sperm SmalScan LowDensityPolyethylene