使用溶解-再结晶策略获得缺陷的碳,用于减少氧气,电催化
Da Bi1, Nailu Shen1, Zeming Tang1
1College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, 29 Jiangjun Ave., Nanjing 210016, China.
ACS applied materials & interfaces
|June 15, 2023
概括
使用简单的溶解-再结晶策略合成了无添加剂的有缺陷的碳纳米棒. 这些材料显示出优异的氧降解反应活性和空气电池的潜在用途.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 无添加剂的有缺陷的碳电催化剂为贵金属催化剂提供了一个环保的替代方案.
- 合成这些碳通常需要恶劣的条件,这给缺陷控制和有效利用带来了挑战.
- 开发用于创建活跃缺陷的简单方法对于推动这一领域的发展至关重要.
研究的目的:
- 开发一个简单的合成策略,用于无兴奋剂的有缺陷的碳电催化剂.
- 为了同步控制碳缺陷和质量转移通道.
- 调查合成材料的氧降解反应 (ORR) 的电催化性能.
主要方法:
- 用一种溶解-再结晶策略来设计Zn-MOF-74前体.
- 棒状Zn-MOF-74前体被直接碳化,产生一个维的多孔缺陷碳纳米棒 (d-CNRs).
- 合成的d-CNRs的形态,结构和表面积的特征.
主要成果:
- 合成产生了一维的多孔缺陷碳纳米棒 (d-CNRs),具有独特的孔隙裂嵌套结构.
- d-CNRs表现出高特异性表面积 (2459 m2/g) 与丰富的缺陷和介质孔,作为ORR的活跃地点.
- 该材料表现出优异的ORR电催化活性和分子选择性,在空气电池中表现稳定超过60小时.
结论:
- 溶解-再结晶策略为合成无兴奋剂有缺陷的碳电催化剂提供了一个简单而可控的途径.
- 合成的d-CNR显示出作为ORR和储能应用的高效和稳定的电催化剂的巨大潜力.
- 这种方法克服了复杂的制备条件对高性能无添加剂碳的局限性.
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