NbSe2 Meets C2N: A 2D‐2D Heterostructure Catalysts as Multifunctional Polysulfide Mediator in Ultra‐Long‐Life Lithium–Sulfur Batteries. Issue 36 (12th August 2021)

• Record Type: Journal Article
• Authors: Yang, Dawei; Liang, Zhifu; Zhang, Chaoqi; Biendicho, Jordi Jacas; Botifoll, Marc; Spadaro, Maria Chiara; Chen, Qiulin; Li, Mengyao; Ramon, Alberto; Moghaddam, Ahmad Ostovari; Llorca, Jordi; Wang, Jiaao; Morante, Joan Ramon; Arbiol, Jordi; Chou, Shu‐Lei; Cabot, Andreu
• Is Part Of: Advanced energy materials. Volume 11:Issue 36(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-08-12
• Subjects: C 2N -- heterostructures -- lithium polysulfides -- lithium‐sulfur batteries -- niobium selenides; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202101250
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: The shuttle effect and sluggish conversion kinetics of lithium polysulfides (LiPS) hamper the practical application of lithium–sulfur batteries (LSBs). Toward overcoming these limitations, herein an in situ grown C2 N@NbSe2 heterostructure is presented with remarkable specific surface area, as a Li–S catalyst and LiPS absorber. Density functional theory (DFT) calculations and experimental results comprehensively demonstrate that C2 N@NbSe2 is characterized by a suitable electronic structure and charge rearrangement that strongly accelerates the LiPS electrocatalytic conversion. In addition, heterostructured C2 N@NbSe2 strongly interacts with LiPS species, confining them at the cathode. As a result, LSBs cathodes based on C2 N@NbSe2 /S exhibit a high initial capacity of 1545 mAh g −1 at 0.1 C. Even more excitingly, C2 N@NbSe2 /S cathodes are characterized by impressive cycling stability with only 0.012% capacity decay per cycle after 2000 cycles at 3 C. Even at a sulfur loading of 5.6 mg cm −2, a high areal capacity of 5.65 mAh cm −2 is delivered. These results demonstrate that C2 N@NbSe2 heterostructures can act as multifunctional polysulfide mediators to chemically adsorb LiPS, accelerate Li‐ion diffusion, chemically catalyze LiPS conversion, and lower the energy barrier for Li2 S precipitation/decomposition, realizing the "adsorption‐diffusion‐conversion" of polysulfides. Abstract : Heterostructured C2 N@NbSe2 composites with high specific surface area and adjusted interface electronic structure are demonstrated as excellent catalysts in lithium–sulfur batteries (LSBs). The promoted adsorption capacity and catalytic effect are fully proved by experiments and theoretical calculation, and batteries based on the C2 N@NbSe2 /S cathode with exceptional lifespan are delivered.