High Performance Hybrid Supercapacitors Based on Designed Ordered Mesostructures/Nanocrystals

Jinwoo Lee 

Department of Chemical Engineering, Pohang University of Science and Technology

Abstract: Ordered mesostructured materials have attracted much attentions as electrodes for energy conversion and storages due to well-interconnected pores, tunable and well-defined pores, high surface area and controllable wall compositions. We report a facile ‘one-pot’ synthesis of ordered mesoporous reduced tungsten oxide/carbon by the evaporation-induced self-assembly (EISA) method. Because of its mesoporous structure and high intrinsic density of tungsten oxide, the resulting material exhibits a high average volumetric capacitance of 340 F cc-1. The good performance of m-WO3-C-s is attributed to the high surface area arising from the mesoporous structure and the low internal resistance from the well-dispersed reduced tungsten oxide and amorphous carbon composite structures. We introduce an advanced hybrid supercapacitor based on a mesoporous Nb2O5/Carbon nanocomposite anode. The highly ordered mesoporous Nb2O5/Carbon nanocomposite (denoted as m-Nb2O5-C) was synthesized by the block copolymer-assisted one-pot synthesis. The Nb2O5 has high theoretical capacity (~ 200 mAh g-1) with incommensurable rate performance as a result of a pseudocapacitive behavior within a stable voltage range (> 1 V). In this work, owing to synergistic effects of (i) pseudocapacitive behavior of Nb2O5, (ii) ordered mesoporous structure (~ 30 nm pores, surface area: ~ 80 m2 g-1) and (iii) carbon composite, the m-Nb2O5-C-based device exhibited high reversible capacity and excellent rate performance with stable cyclability both in lithium ion battery system (~ 180 mAh g-1 at 0.01 A g-1 and ~ 120 mAh g-1 at 5 A g-1 and ~ 80% capacity retention at 2 A g-1 during 4000 cycles) and m-Nb2O5-C//MSP-20 HSC system (~ 74 Wh kg-1, 18,510 W kg-1).


Biography:

1998 B.S. School of Chemical and Biological Engineering (Chemical Technology), Seoul National University, Seoul, Korea

2000 M. S. School of Chemical and Biological Engineering, College of Engineering,

Seoul National University, Seoul, Korea

2003 Ph.D. School of Chemical and Biological Engineering, College of Engineering,

Seoul National University, Seoul, Korea

 

9/17~   Professor

Department of Chemical Engineering, Pohang University of Science and Technology

9/12-8/17 Associate Professor 

Department of Chemical Engineering, Pohang University of Science and Technology

 

06/08-08/12 Assistant Professor

Department of Chemical Engineering, Pohang University of Science and Technology

 

09/05-05/08 Postdoctoral Research Associate

Post-doctoral Research Associate, Department of Material Science and Engineering and Cornell Fuel-Cell Institute, Cornell University

Topics:

1) Synthesis of thermally stable ordered mesoporous metal oxides using block copolymers for energy applications

2) Development of high performance fuel cell electrocatalyst

Supervisor: Prof. Ulrich Wiesner and Prof. Francis DiSalvo

 

09/03-08/05 Postdoctoral Researcher

School of Chemical and Biological Engineering, College of Engineering,

Seoul National University, Seoul, Korea

Topic: Templated nanostructured carbon materials for biosensors, biocatalysis and energy storage

Supervisor: Prof. Taeghwan Hyeon


Publication Record (~2017.07.20)

160 SCI papers, total citation times: 12236 (Google Scholar) and 10087 (Web of Science), H-index: 51 (Google Scholar) and 48 (web of science)

85 SCI papers during recent 5 years, Average impact factor 8.16

Nat. Mater. (1), J. Am. Chem. Soc. (4), Angew. Chem. Int. Ed. (3), ACS Nano (8), Energy Environ. Sci. (3), Adv. Funct. Mater. (7), Adv. Mater. (3), Adv. Energy Mater. (3)