Zhou Zhiyou

Study of pyrolyzed hemin/C as non-platinum cathodic catalyst for direct methanol fuel cells

Biological reduction of O2 to H2O justifies a serious look at heme as a potential O2 reduction reaction (ORR) catalyst for low temperature fuel cells. In this study, a novel non-platinum electrocatalyst for ORR was prepared through hemin, which is hydrochloride of heme, supported on Black Pearls 2000 carbon black (Hm-BP) pyrolyzed at 700–900 °C in Ar atmosphere. The physical and electrocatalytic properties of as-prepared catalysts were characterized by TGA, XRD, XPS, TEM, rotating disk electrode (RDE) and rotating ring disk electrode (RRDE). It has found that the catalyst treated at 750 °C (Hm-BP-750) exhibits the best property among the Hm-BP catalysts prepared. The onset potential of ORR on the Hm-BP-750 at 30 °C was measured ca. 0.90 V (vs. RHE) in 0.1 M H2SO4, and mass current density was reached 15.3 mA mg−1 at 0.75 V. It has revealed that O2 could be reduced directly to water in a 4e process between 0.9 and 0.83V, and the yield of H2O2 was 0–18% in the potential range of 0.83–0.63 V. This methanol-tolerant catalyst also presents excellent stability in medium-term test of direct methanol fuel cell at 80 °C.

铁、氮掺杂石墨烯/碳黑复合材料的制备及氧还原电催化性能

以高含氮量的2-氨基咪唑为氮源,三氯化铁为铁源,高比表面积的KJ600碳黑为载体,通过水热法制得氨基咪唑聚合物前驱体,再经二次高温热处理,制得石墨烯/碳黑复合材料.透射电镜表征显示该材料为石墨烯纳米片与碳黑颗粒的复合结构.BET表征表明这是一种多孔结构,具有很高的比表面积（882 m~2·g~（-1））,这有利于暴露更多活性位点,并促进传质.XRD证实催化剂中存在石墨烯,且石墨烯结构是在第一次热处理过程中形成的.电化学测试表明,该催化剂在酸性和碱性介质中都具有很高的氧还原电催化活性和低H_2O_2产率,并且在碱性介质中对甲醇小分子的抗毒化性能明显优于商业Pt/C催化剂,展示出在实际燃料电池系统中的应用潜力.

Preparation of Dendritic Pt Thin Films and Their Anomalous Infrared Effects

National Natural Science Foundation of China [21073152, 20933004, 20833005, 21021002]; Outstanding Young Scientific Talents Cultivation Plan of Colleges in Fujian Province, China [JA10003]