C纳米悬浮液的电流体驱动雾化研究

Electrohydrodynamic atomization of a C nano-suspension

以制备质子交换膜燃料电池膜电极组件扩散层中微孔层的原料——C纳米悬浮液为研究对象,研究了质量分数6%的C纳米悬浮液电流体驱动雾化（electrohydrodynamic atomization,EHDA）的雾化模式及稳定锥柱型雾化模式的形成条件。在稳定锥柱模式下,研究了雾化参数（电压、流量及沉积高度）对沉积颗粒尺寸、分布及沉积膜结构的影响。流量与沉积高度对沉积颗粒的尺寸及分布影响较大,电压的影响相对较小,当流量增大或沉积高度减小时沉积颗粒分布变密集,沉积颗粒的尺寸主要分布在0.2~0.4μm范围内。在不同的沉积高度下,进行C膜的沉积,沉积高度越高C膜结构越疏松,沉积高度越低C膜结构越致密。基于此研究,提出了一种基于电流体驱动雾化沉积技术制备质子交换膜燃料电池膜电极组件扩散层及微孔层的方法。

6% C nano-suspension was atomized using electrohydrodynamic atomization （EHDA） technique; the C nano-suspension is the key material for the formation of the micro-porous layer （MPL） of gas diffusion layer （GDL） which is a major part of membrane electrode assembly （MEA） of proton exchange membrane fuel cells （PEMFC）. The different atomization modes and the condition for the formation of stable cone-jet mode were studied. In the stable cone-jet mode, the effect of the atomization parameters （applied voltage, flow rate and working distance） on size and distribution of the deposited droplets and structure of the films were examined. The results showed that the flow rate and working distance had strong influence on the size and distribution of the droplets, while the applied voltage was inconspicuous. The higher flow rate and working distance resulted in dense deposited droplets, which is mainly at the range of 0.2 μm to 0.4 μm. C films were also deposited using C nano-suspension and EHDA technique in stable cone-jet mode at different working distance. At a greater distance dense C films were produced, at a smaller distance porous C films were generated. Based on this research, this work presents a method for the formation of MPL and DL of PEMFC.