Assoc. Prof. Kwun Nam HUI | University of Macau, China
Dr. Kwun Nam HUI, is an Associate professor at the Institute of Applied Physics and Materials Engineering, University of Macau. He obtained Ph.D. degrees in Electrical and Electronic Engineering from the University of Hong Kong in 2009. He has been working as Assistant professor (2009-2013) and Associate professor (2013-2015) in School of Materials Science and Engineering at Pusan National University. As Principle Investigator, he has managed 36 research projects including 4 projects from National Research Foundation of Korea with a total research grant of USD 2 million. His research has led to 1 US patent, 7 granted CN patents, 17 CN patent-pending, 10 granted KR patents, and 250 SCI journal papers. Dr. KN Hui has h-index (Google): 57; Citations: 9924. His current research interests include Li/Na/K/Al-ion batteries, hybrid Na-air battery, fuel cell, as well as metal/heteroatom-doped carbon electrocatalysis for oxygen reduction reaction, oxygen evolution reaction, and hydrogen evolution reaction.
Speech title / Enhancing Electrochemical Stability of Phosphorus-based Anode for Potassium-Ion Battery with Amorphous Zinc Phosphate Additive
Abstract: Black phosphorus (BP) presents high theoretical capacity as potassium-ion battery (PIB) anode. However, some key issues, including low ionic/electronic conductivity for bulk BP, high volume expansion, and sensitivity to humid environment for BP nanomaterials, hinder its practical applications. Here, we proposed and introduced amorphous zinc phosphate into the BP to form amorphous BP nanocomposites. The amorphous zinc phosphate has multifunctional roles in weakening the agglomeration of BP nanomaterials, reducing the volume expansion, and improving the environmental stability of BP nanocomposite electrodes in humid air. The optimized amorphous BP nanocomposite with 30wt% zinc phosphate (BP@C@ZPO[30]) as PIB anode exhibited enhanced cycling stability in a noninflammable triethyl phosphate (TEP) electrolyte (retained capacity of 369.0 mA h g–1 after 500 cycles at 0.5 A g–1), and the volume expansion rate of the BP@C@ZPO(30) electrode is reduced to 47% compared with BP@C@ZPO(0) electrode of 100%. More importantly, the presence of amorphous zinc phosphate improves the environmental stability of the BP nanocomposite electrode in the humid air on the basis of its strong and fast physical absorption to water. Therefore, the BP@C@ZPO(30) electrode delivers a reversible capacity of 629.2 mA h g–1 (200 cycles at 0.2 A g–1) even after exposure of the electrode to humid air for two days. Such a simple and effective strategy is beneficial to accelerate the practical application of phosphorus electrode.