Greenhouse gases, such as carbon dioxide, have a great impact on global warming and climate change. CO₂ trapping and reduction have been one of the solutions to slow down the temperature rise. Copper has proven to be an effective electrocatalyst to transform CO₂ into useful organic compounds, such as CH₄, C₂H_4, and HCOOH. Here, nanoporous copper (NPC), that are synthesized from various precursor phases of Cu–Al alloys, like pure Al solid solution α, CuAl₂ θ and CuAl η phases, with different relative densities and ligament sizes are being used as electrocatalyst for CO₂ reduction reaction (CO₂RR). The ligament sizes of the NPCs can be adjusted with the use of dealloying solution, either in HCl or NaOH, and dealloying temperatures. In this study, the ligament sizes were available from the range of 51–116 nm. A hierarchical structure containing a lamellar eutectic structure with an interlayer spacing of 6 μm in the parent phases is observed from NPC synthesized from Cu₁₈Al₈₂. The results show that the current density of CO₂RR using NPC as electrocatalyst is 2–5 times higher than that of using copper foil. The ligament size effect is more obvious than the relative density effect since the peak current density was obtained from the NPC with ligament size of 76 nm. The product distribution suggested that NPC with hierarchical structure has higher Faraday efficiency of ethylene than conventional NPC or Cu foil at high overpotential.

二氧化碳等温室气体对全球变暖和气候变化具有重大影响。捕获和还原CO ₂已成为减缓温度上升的解决方案之一。事实证明，铜是将CO ₂转化为有用的有机化合物（例如CH ₄，C ₂ H ₄和HCOOH）的有效电催化剂。在这里，由Cu-Al合金的各种前驱物相（如纯Al固溶体α，CuAl _2θ和CuAlη相）合成的具有不同相对密度和韧带尺寸的纳米孔铜（NPC）被用作CO的电催化剂。₂还原反应（CO ₂RR）。NPC的韧带尺寸可通过使用HCl或NaOH中的脱合金溶液和脱合金温度进行调节。在这项研究中，韧带的大小范围为51–116 nm。从Cu ₁₈ Al ₈₂合成的NPC观察到母体相中层间共层间隔为6μm的层状共晶结构的分层结构。结果表明，CO ₂的电流密度使用NPC作为电催化剂的RR比使用铜箔的RR高2-5倍。韧带尺寸效应比相对密度效应更明显，因为峰值电流密度是从韧带尺寸为76 nm的NPC获得的。产品分布表明，在高超电势下，具有分层结构的NPC具有比常规NPC或Cu箔更高的乙烯法拉第效率。