Charge injection into the Ni-phyllosilicate nanoscrolls with reduced Ni nanoparticles using Kelvin force probe microscopy

The evolution of the electrical charge injected into Ni-doped phyllosilicate nanoscrolls composites deposited on a conductive substrate was studied by Kelvin probe force microscopy. The nanoscrolls were synthesized by hydrothermal method and then annealed in H2/Ar flow at 400-900degC in order to reduce Ni up to metal. A typical agglomerate of the Ni3Si2O5(OH)4 nanoscrolls accumulated the charge on one nanoscroll followed by a subsequent partial destruction of the agglomerate. For the Ni2MgSi2O5(OH)4 nanoscrolls, the whole agglomerate could be charged, and the injected charge was retained for hours. The shortest charge relaxation time was revealed for the nanoscrolls annealed at the highest temperature, when Ni was completely reduced.