喷雾干燥法制备铂镍合金三维纳米骨架材料及增强甲醇氧化性能研究

本文以氯铂酸氨和氯化镍为原料,氯化铵作为造孔剂,通过雾化干燥法结合煅烧还原制备铂镍合金三维纳米骨架材料,该新型材料可增强催化甲醇氧化性能。重点研究了前驱体中加入氯化铵和不加入对铂镍合金三维纳米骨架形成的影响规律,研究不同结构的铂镍合金三维纳米骨架材料对催化氧化甲醇活性和稳定性的影响规律。研究结果表明,通过加入适量的氯化铵作为造孔剂,制备的铂镍合金为单项固溶体结构(面心立方结构),由弯曲纳米线交织组成三维纳米骨架材料,纳米线直径小于10 nm,纳米孔10 nm左右；与商用Pt黑和不加入氯化铵制备的铂镍合金纳米材料相比,PtNi合金三维纳米骨架材料具有更高的甲醇催化氧化活性(611.4 mA.mg_^-1Pt),分别是商用Pt黑的3.58倍(170.8 mA.mg_^-1Pt)和PtNi合金纳米材料(不加氯化铵)的1.36倍(448.8 mA.mg_^-1Pt)；在催化甲醇氧化性能稳定性上,PtNi合金三维纳米骨架材料表现出最好的稳定性,稳定性顺序为：PtNi合金三维纳米骨架材料 > PtNi合金纳米材料(不加氯化铵)> 商用Pt黑。此外,本文对该方法进行了扩展,成功的制备了铂镍钴铜钌铱钯(PtNiCoCuRuIrPd)高熵合金三维纳米骨架材料。

Preparation of PtNi alloy 3D-nanoframeworks by spray drying for enhancing catalytic oxidation performance of methanol

The chloroplatinic acid and nickel chloride as raw materials, ammonium chloride as pore-forming agent, are used to synthesize PtNi alloy 3D-nanoframeworks materials by spray drying method combined with calcination reduction. The PtNi alloy 3D-nanoframeworks materials can enhance catalytic oxidation performance of methanol. The influence of ammonium chloride or no chloride on the formation of PtNi alloy 3D-nanoframeworks materials was studied, and the effects of PtNi alloy 3D-nanoframeworks with different structures on the activity and stability of catalytic methanol oxidation were investigated in detail. The results showed that the PtNi alloy prepared by adding appropriate amount of ammonium chloride has a single solid solution structure (fcc), which is composed of curved nanowires interwoven to form 3D-nanoframeworks. And the diameter of the nanowires is less than 10 nm, and the nanopore is about 10 nm. Compared with commercial Pt black catalysts and PtNi alloy nanomaterials without ammonium chloride, PtNi alloy 3D-nanoframeworks materials has higher catalytic methanol oxidation activity (611.4 mA·mg-1Pt), which is 3.58 times (170.8 mA·mg-1Pt) of commercial Pt black and 1.36 times (448.8 mA·mg-1Pt) of PtNi alloy nanomaterials without ammonium chloride, respectively. The order of stability in catalytic methanol oxidation reaction is: PtNi alloy 3D-nanoframeworks materials > PtNi alloy nanomaterials without ammonium chloride >commercial Pt black catalyst. In addition, In this paper, the method is extended to successfully prepare PtNiCoCuRuIrPd high-entropy-alloy 3D-nanoframeworks materials.