A Comparison of Pt/Si and Pt_3Cu/Si Schottky nano-heterojunctions: enhanced direct methanol energy converter based on non-adiabatic system and molecular adsorption

摘要

In order to utilize the miniaturization exothermic oxidation of methanol in the microelectronic device as an energy source rather than industrial waste, nano-heterojunctions between Si and 20 nm ultra-thin catalyst Pt~(3)Cu or Pt film were fabricated to investigate the energy conversion of methanol in this study. Methanol was catalyzed by Pt~(3)Cu or Pt to release energy, then electrons were excited and passed through the Schottky barrier of Pt~(3)Cu/Si or Pt/Si, which were calculated to be 0.43 and 0.80 eV, respectively. Thereupon, hot electron current was formed in a ballistic transport mode. Pt~(3)Cu, Pt and Si have good high temperature stability. Pt~(3)Cu has a higher crystallinity and better electronic structure than Pt and is dominated by (111) crystal orientation. Thus, Pt~(3)Cu has higher catalytic activity and stronger ability to overcome the toxicity of CO, making it easier to obtain stable hot electron current. The factors that affect the hot electron current are varied from chemical reaction rate to Au electrode structure with the increase of temperature. This work is likely to provide a new reference to enhance the methanol’s direct conversion effectively with a stable current in the solid-state way at different temperature. Herein we report for the first time achieving methanol as hot electron energy source. Therefore, the maximum utilization of energy could be realized by turning waste methanol into treasure.