1. A resistive switching device, comprising a first electrode comprising a first metal material; a switching material, the switching material comprising an amorphous silicon material; a second electrode comprising at least a second metal material; and a buffer material disposed between the first electrode and the switching material, the buffer material providing a blocking region between the switching material and the first electrode, the blocking region being substantially free from metal particles from the second metal material when a first voltage is applied to the second electrode.