Diatomite-like KFeS2 for Use in High-Performance Electrodes for Energy Storage and Oxygen Evolution

Can Wang; Kailin Li; Qing Sun; Shijin Zhu; Chenzhi Zhang; Yunhao Zhang; Zhongyi Shi; Youzhong Hu; Yuxin Zhang

doi:10.3390/nano13040643

Diatomite-like KFeS₂ for Use in High-Performance Electrodes for Energy Storage and Oxygen Evolution

Nanomaterials (Basel). 2023 Feb 6;13(4):643. doi: 10.3390/nano13040643.

Authors

Can Wang¹, Kailin Li¹, Qing Sun², Shijin Zhu¹, Chenzhi Zhang¹, Yunhao Zhang³, Zhongyi Shi⁴, Youzhong Hu¹, Yuxin Zhang¹

Affiliations

¹ College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China.
² Multi-Scale Porous Materials Center, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China.
³ School of Energy and Power Engineering, Chongqing University, Chongqing 400044, China.
⁴ Undergraduate School, Chongqing University, Chongqing 400044, China.

Abstract

Bifunctional materials possess remarkable properties that allow them to store and convert electrical energy easily. In this paper, diatomite-like potassium iron disulfide (KFeS₂) was synthesized by a multistep sacrificial template method, and its morphological, electrochemical, and oxygen evolution reaction (OER) properties were investigated. KFeS₂ was found to be porous, hollow, and cake-like, which suggests a high specific surface area (SSA) and abundant electrochemically active sites. A very high specific capacitance of 651 F g^-1 at 1.0 A g^-1 was also obtained due to the substance's unique structure and high porosity. Additionally, the diatomite-like KFeS₂ possessed a very low overpotential ƞ₁₀ of 254 mV at a current density of 10 mA cm^-2 and a small Tafel slope of about 48.4 mV dec^-1. Thus, the diatomite-like KFeS₂ demonstrates broad application prospects for both energy storage and conversion.

Keywords: KFeS2; diatomite; hydrothermal synthesis; oxygen evolution reaction; supercapacitors.

Grants and funding

This research was funded by the National Natural Science Foundation of China (Grant No. 51908092), Projects (No. 2020CDJXZ001, 2021CDJJMRH-005 and SKLMT-ZZKT-2021M04) supported by the Fundamental Research Funds for the Central Universities, the Joint Funds of the National Natural Science Foundation of China-Guangdong (Grant No. U1801254), the project funded by Chongqing Special Postdoctoral Science Foundation (XmT2018043), the Chongqing Research Program of Basic Research and Frontier Technology (cstc2017jcyjBX0080), the Natural Science Foundation Project of Chongqing for Post-doctor (cstc2019jcyjbsh0079 and cstc2019jcyjbshX0085), Technological Projects of Chongqing Municipal Education Commission (KJZDK201800801), the Innovative Research Team of Chongqing (CXTDG201602014), and Innovative Technology of New Materials and Metallurgy (2019CDXYCL0031).