電化學轉化二氧化碳對於開發新的替代能源是極具潛力的。如何將二氧化碳有效地轉化成有價值的化學產物是一個非常重要的關鍵。本篇使用電化學沉積奈米級的樹狀金於碳纖維紙上，奈米金沿著(111)面對疊成充滿尖端及稜角的三維對稱結構，不僅提供大量的電化學活性表面積提供催化，而且其結構穩定，並透過光的輔助激發樹狀金電極的表面電子形成表面電漿共振(Surface Plasmon Resonance, SPR)，形成光電催化。樹狀金電極透過循環伏安法所得數據計算金的電化學活性表面積為 78 cm2 (物理表面積為 1 cm2)，放大至少 70倍以上。樹狀金電極也具有良好的起始電位(-0.9 V vs. SCE, -0.22 V vs. RHE)。因為電解液有氫離子的存在，所以二氧化碳與氫離子會競爭電子，但在-1.2 V vs. SCE較低的過電位下一氧化碳的法拉第效率接近80%，遠大於氫氣的 20%。光電催化轉化二氧化碳雖然沒辦法增加一氧化碳的法拉第效率，但是由於表面電漿共振的關係提升電流值，其電流增幅約為22%，而有更多的電子提供催化，增加還原產物的量。 Elecrtochemical conversion of CO2 has great potential for newable energy storeage. How to convert CO2 to valuable chemicals effectively and efficiently represents a keypoint in catalysis research. The deposited Au dendrites (Au-D) on the CFP electrode shows a three-fold symmetric structure and is composed of trunks, branches and nanorod leaves. And the Au structure grows all along the <111> direction. This kind of composition contains a large number of tips and edges in nanoscale, not only provides a large electrochemical active surface (ECSA) but also has been attributed illumination excite Au-D surface electron that cause Surface Plasmon Resonance (SPR). Electrochemical activity surface area (ECSA) of Au-D of Au-D were explored by CV that is 78 cm2 when its physical surface area equals to 1 cm2. Au-D also has low onset potential ‒0.22 V vs. reversible hydrogen electrode (RHE) in conversion of CO2.When H2O exists, hydrogen evolution reaction (HER) usually compete with CO2 reduction. In our work, Au-D electrode displayed great activity to convert CO2 to CO with high Faradic efficiency (FE) of 80% at low overpotential (‒0.52 V vs. RHE) which is larger than H2. Photoelectrocatalytic conversion of carbon dioxide does not increase the CO Faraday efficiency, but the current is increased by SPR (current is increased 22%). Due to more electrons of photoelectrocatalytic, so the amount of reduction products is increased.
