结合聚合物框架中的侧链修改用于电催化氧进化反应
Neelam Gupta1, Sayan Halder2, Ravi Prakash Behere1
1Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India.
ACS applied materials & interfaces
|June 6, 2023
概括
研究人员开发了无金属结合聚合物框架 (CPF) 用于氧化演化反应 (OER) 电催化. 侧链工程显著提高了OER活动和耐用性,显示了可持续能源应用的前景.
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:
- 结合聚合物框架 (CPF) 在光催化,传感和能量储存方面显示出潜力.
- 由于其骨干结构,CPF往往缺乏可溶性和可加工性.
- 氧化演化反应 (OER) 的无金属电催化剂尚未得到充分研究.
研究的目的:
- 开发和研究基于氨酸的无金属电催化OER的供体-受体CPF.
- 探索不同侧链 (基与橄乙烯甘醇) 对CPF电催化性能的影响.
- 评估合成CPF的OER活动,耐用性和结构-属性关系.
主要方法:
- 合成两种基于三的供体-受体CPF,具有不同的侧链 (CPF1:hexyl,CPF2:oligoethylene glycol).
- 电化学表征,包括OER活性和耐久性测试.
- 密度函数理论 (DFT) 计算以支持实验发现.
主要成果:
- 这两种CPF都表现出优越的电催化OER活性和长期耐用性.
- 与CPF1 (488 mV) 相比,CPF2 (橄乙烯糖醇侧链) 显示显著提高了OER性能 (10mA/cm2在328 mV超电位下)
- 多孔纳米结构促进了电荷/质量传输;增强的水友性和 CPF2 中减少的 π-π 堆叠有助于其优越的活动.
结论:
- 无金属的CPF是OER的有希望的电催化剂.
- 侧链工程,特别是与极性,水友群,如乙烯甘醇,可以显著提高OER性能.
- 进一步修改侧链有可能优化CPF电催化剂的OER.
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