以甲烷为碳源, 采用化学气相沉积(CVD)法制备了尺寸均匀(粒径在50~140 nm)的带有金属核心的纳米洋葱碳(CNOs)。通过微波加热对合成的CNOs进行纯化得到纯度为99%的洋葱碳材料, 并作为双极板导电填料应用于质子交换膜燃料电池(PEMFCs)电堆。通过CNOs的表征和分析表明, 合成的CNOs中内嵌Fe-Ni纳米金属粒子。由接触角测试可知, 注塑工艺制备的洋葱碳基双极板的润湿角低于91°, 亲水性较商用石墨双极板有所改善, 有利于电子的传输。经自呼吸电堆耐久性和功率测试发现, 由洋葱碳基双极板组装的电堆在13.2 V下的输出功率达到58 W, 比商业石墨双极板电堆输出功率(48 W)提高21%。研究证实洋葱碳基复合材料可以提高PEMFCs电堆的功率密度、效率及寿命。

Metal-core carbon nano-onions (CNOs) with uniform size(50~140 nm) were prepared by chemical vapor deposition (CVD) method with methane as carbon source. The synthesized CNOs were purified by microwave heating to obtain an onion carbon material with a purity of 99%, and it was used as conductive bipolar plate in proton exchange membrane fuel cells (PEMFCs) stack. The characterization and analysis of CNOs show that the synthesized CNOs are embedded with Fe-Ni nanoparticles. The contact angle test reveals that the wetting angle of the onion carbon-based bipolar plate manufactured by injection molding is less than 91°, and the hydrophilicity is enhanced compared to the commercial graphite bipolar plate, which is helpful to electron transmission. The output power of the stack formed using onion carbon-based bipolar plates reaches 58 W at 13.2 V, which is 21% greater than that of the commercial graphite bipolar plate stack (48 W), according to the endurance and power test of the self-breathing stack. Onion carbon-based composites have been shown in studies to enhance the power density, efficiency, and longevity of PEMFCs stack.