Halloysite-derived nitrogen doped carbon electrocatalysts for anion exchange membrane fuel cells
Halloysite-derived nitrogen doped carbon electrocatalysts for anion exchange membrane fuel cells
复制标题
DOI：
10.1016/j.jpowsour.2017.10.037
复制
发表时间：
2017-12-31
影响因子：
9.2
通讯作者：
Cai, Qiong
中科院分区：
文献类型：
--
作者：
Lu, Yaxiang;Wang, Lianqin;Cai, Qiong
开发用于氧还原反应（ORR）催化剂的低成本、高活性碳质材料一直是耐用燃料电池的优先研究方向。本文以天然埃洛石为模板，分别以尿素氮源以及葡萄糖（表示为GU）和糠醛（表示为FU）碳前体获得了两种新型的片状和棒状形貌的氮掺杂碳质材料，它们可以直接用作碱性电解质中ORR的无金属电催化剂。重要的是，与基准 Pt/C (20wt%) 催化剂相比，所制备的碳催化剂表现出更高的扩散限制电流密度保留率（3000 次循环后）和增强的甲醇耐受性，半波电位负移仅为 50-60mV。此外，电催化活性、耐久性和甲醇耐受性也揭示了棒状催化剂性能优于片状催化剂的根本原因。最后，所生产的碳质催化剂也被用作单电池H-2/O-2阴离子交换膜燃料电池（AEMFC）的阴极，其中棒状FU的峰值功率密度高达703 mW cm(-2)（而使用Pt/C基准阴极催化剂时为1106 mW cm(-2)）。
Developing the low-cost, highly active carbonaceous materials for oxygen reduction reaction (ORR) catalysts has been a high-priority research direction for durable fuel cells. In this paper, two novel N-doped carbonaceous materials with flaky and rod-like morphology using the natural halloysite as template are obtained from urea nitrogen source as well as glucose (denoted as GU) and furfural (denoted as FU) carbon precursors, respectively, which can be directly applied as metal-free electrocatalysts for ORR in alkaline electrolyte. Importantly, compared with a benchmark Pt/C (20wt%) catalyst, the as-prepared carbon catalysts demonstrate higher retention in diffusion limiting current density (after 3000 cycles) and enhanced methanol tolerances with only 50-60mV negative shift in half-wave potentials. In addition, electrocatalytic activity, durability and methanol tolerant the underneath reasons of the outperformance of rod-like catalysts over the flaky are revealed. At last, the produced carbonaceous catalysts are also used as cathodes in the single cell H-2/O-2 anion exchange membrane fuel cell (AEMFC), in which the rod-like FU delivers a peak power density as high as 703 mW cm(-2) (vs. 1106 mW cm(-2) with a Pt/C benchmark cathode catalyst).