| 학회 | 한국재료학회 |
| 학술대회 | 2020년 가을 (11/18 ~ 11/20, 휘닉스 제주 섭지코지) |
| 권호 | 26권 1호 |
| 발표분야 | 특별심포지엄6. 차세대 배터리 심포지엄-오거나이저: 김종순(세종대) |
| 제목 | Operando observation of Zn metal plating/stripping in aqueous batteries |
| 초록 | Utilizing Zn metal as an anode in aqueous batteries, however, suffers from low coulombic efficiency caused by a dendritic Zn plating and formation of byproducts such as hydrogen gas, solid zinc hydroxide and salt-related compounds. An effective way of mitigating the issues is to modify the solvation structure of the electrolyte to increase the energy barrier of the water molecules for hydrolysis and electrolysis. Nevertheless, Zn aqueous batteries still indiscriminately utilize several types of electrolytes without elucidating the correlation between electrolyte composition and the electrochemistry of Zn metal. Here, we use operando optical microscopy to visualize the microstructural evolution of Zn metal, which strongly affects the electrochemical reversibility. In ZnSO4 electrolyte, large Zn platelets grow and form loose agglomerates vulnerable to unexpected delamination from the electrodes. In Zn(OTf)2 electrolyte, Zn platelets nucleate more homogeneously and grow smaller, which forms denser agglomerates enabling more stable cycling. We further reveal that the formation of a stable solid-electrolyte interphase layer holds the key to the excellent performance of acetonitrile-hybrid water-in-salt electrolytes. Our results show the necessity of designing proper electrolytes to develop long-life Zn aqueous batteries. ref) J. Power Souces, 2020, 472, 228334 |
| 저자 | 홍지현 |
| 소속 | 한국과학기술(연) |
| 키워드 | Zn-ion batteries; aqueous batteries; electrodeposition; optical microscopy; solid-electrolyte interphase |
