分论坛会议报告:Superwetting Micro-/nanostructured Electrodes for Gas-InvolvedElectrocatalysis

发布时间:2016-10-24|阅读次数:26

 

Xiaoming Sun*, Yingjie Li, Wenwen Xu, Zhiyi Lu

Beijing University of Chemical Technology, Beijing 100029, China

 

Electrochemical gas-involved reactions can be divided into two types: gas-evolution reaction and gas-consumption reaction, both of which are crucial for a variety of energy conversion processes and industries (e.g. HER and ORR). For gas-evolution reaction, if generated gas bubbles pin at the electrode surface and cannot escape from the surface in time, the accumulated bubbles will reduce the effective electrode surface area, increase diffusion resistance and enlarge polarization effect, resulting in more energy consumption. How to construct a novel electrode to promote gas bubble release is critical for improving the electrochemical efficiency besides activity improvement. Inspired from bio-inspired superwetting surfaces, we found that the interface behavior of electrode could be tuned by surface architecture construction, for example, transferring from aerophobic to superaerophobic by engineering a series of micro-/nanostructured electrode, e.g. MoS2, pine-shaped Pt, NiFeLDHs and Cu films [1-6]. This kind of superaerophobic electrodes could decrease the critical size of gas overflowing from the surface by cutting the three phase contact lines into discontinue dots, and thus reduce the diffused impedance and maintain the integrity of the solid−liquid interface that is necessary for electrocatalysis (e.g. water splitting and hydrazine fuel cells). On the other hand, for gas-consumption reaction, the construction of micro-/nanostructedsuperaerophilic electrode could accelerate gas diffusion to reaction zone via gas-phase to solve the issue of low solubility and slow diffusion of gases in traditional electrocatalysis reaction system with limited current density (e.g., ORR). Therefore, the construction of superwetting electrodes is imperative to improve gas transport at electrodes surface and to enhance activity and stability of electrodes.

 

References

[1] Z. Lu, W. Zhu, X. Yu, H. Zhang, Y. Li, X. Sun, X. Wang, H. Wang, J. Wang, J. Luo, X. Lei, L. Jiang. Adv. Mater. 26(2014) 2683-2687.

[2] Y. Li, H. Zhang, T. Xu, Z. Lu, X. Wu, P. Wan, X. Sun, L. Jiang. Adv. Funct. Mater. 25( 2015) 1737-1744.

[3] Z. Lu, M. Sun, T. Xu, Y. Li, W. Xu, Z. Chang, Y. Ding, X. Sun, L. Jiang. Adv. Mater. 27(2015) 2361-2366.

[4] X. Liu, Z. Chang, L. Luo, T. Xu, X. Lei, J. Liu, X. Sun. Chem. Mater., 26(2014) 1889-1895.

[5] M. Sun , Z. Lu , L. Luo, Z. Chang , X. Sun. Nanoscale, 8(2016),: 1479-1484

[6] W. Xu, Z. Lu, P. Wan, Y. Kuang, X. Sun. Small, 2016, accepted.

 

Biography

Professor Xiaoming Sun gained his B.S. degree and Ph.D. in Department of Chemistry, Tsinghua University in 2000 and 2005, respectively. After postdoctoral work at Stanford University, he joined State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology at 2008. His main research interests focus on separation and assembly of inorganic nanostructures, synthesis and separation of carbon nanomaterials and their composites, and structure control, opto-/electro-property investigations of nanoarrays and  superwetting micro-/nanostructure electrodes for energy sciences. He has authored 63 journal articles (e.g.J. Am. Chem. Soc., Angew. Chem. Int. Ed., Adv. Mater., ACS Nano.), which have been cited >4600 times.