甲酸作为一种液体燃料和化学原料，在资源循环利用中具有重要意义，而电催化还原 CO2是将 CO2 转化成甲酸的几大主要方法之一。因为 CO2分子的稳定性，因此需要能够有效提高反应速率和降低反应活化能的催化剂。本文以磁性金属合金纳米晶为研究对象，利用溶剂热法合成一系列不同配比的纳米合金，并研究其催化性能的变化情况，以得到最优催化条件。 在本论文中，我们成功合成了含有Fe，Co，Ni 的合金纳米晶，包括CoNi合金，FeCo 合金，Fe3Co7合金，Fe7Co3合金，FeNi3 合金Fe7Ni3 合金纳米晶。这些合金的纯度较高，尺寸分布在 50 nm到500 nm之间。将合成的纳米合金用于电催化性能测试，结果发现 CoNi 合金纳米晶在 KHCO3 溶液作为电解质时的电催化CO2 还原的性能最佳，线性扫描曲线表示，相比于空白的过电位，CoNi 合金的过电位更加接近于0 V，并且电流密度较大。在-1.18 V恒电位电解1 小时后电流密度只有小幅度波动，表明该催化剂电催化性能稳定。

The use of formic acid as a fuel and chemical feedstock could become very important in the development of resource recycling. However, formic acid could be efficiently obtained from the electrochemical CO2 reduction. Because of the stability of CO2 molecules, the catalyst of the reaction need to be able to effectively improve the reaction rate and lower the activation energy. In this paper, we study the transition metal nano-alloys by using a solvent thermal synthesis to get nano-alloys that have different ratios, then we study changes in its catalytic properties in order to obtain the optimal catalytic conditions. In this paper, We successfully synthesized nano-alloys containing iron, cobalt, nickel, including CoNi alloy, FeCo alloy, Fe3Co7 alloy, Fe7Co3 alloy, FeNi3 alloy, Fe7Ni3 alloys. These alloys are of high purity, and their size are between 50nm to 500nm. Then we test the electrocatalytic performance of these nano-alloys and found CoNi alloys with KHCO3 solution as an electrolyte has best performance in CO2 electrocatalytic reduction. The LSV result represents that compared to the blank, its overpotential is closer to 0V, and the current density is higher. The CPE experiment shows that current density is only a slight fluctuation in -1.18V for 1 hour electrolysis experiment, indicating the stability of the catalyst.