Crystal Facet Engineering Induced Active Tin Dioxide Nanocatalysts for Highly Stable Lithium–Sulfur Batteries

Abstract

Controlling exposed crystal facets through crystal facet engineering is an efficient strategy for enhancing the catalytic activity of nanocrystalline catalysts. Herein, the active tin dioxide nano–octahedra enclosed by {332} crystal facets (SnO2 {332}) are synthesized on reduced graphene oxide and demonstrate powerful chemisorption and catalytic ability, accelerating the redox kinetics of sulfur species in lithium–sulfur chemistry. Attributed to abundant unsaturated–coordinated Sn sites on {332} crystal planes, SnO2 {332} has outstanding adsorption and catalytic properties. The material not only adsorbs and converts polysulfides efficiently, but also prominently lowers the decomposition energy barrier of Li2S. The batteries with these high active electrocatalysts exhibit excellent cycling stability with a low capacity attenuation of 0.021% every cycle during 2000 cycles at 2 C. Even with a sulfur loading of 8.12 mg cm−2, the batteries can still cycle stably and maintain a prominent areal capacity of 6.93 mAh cm−2 over 100 cycles. This research confirms that crystal facet engineering is a promising strategy to optimize the performance of catalysts, deepens the understanding of surface structure‐oriented electrocatalysis in Li–S chemistry, while aiding the rational design of advanced sulfur electrodes.

Electrocatalyst Modulation toward Bidirectional Sulfur Redox in Li–S Batteries: From Strategic Probing to Mechanistic Understanding

“…Along this line, Jiang et al synthesized SnO 2 nano-octahedron with highly exposed (332) and ( 111) crystal facets on graphene (denoted as SnO 2 (332)-G and SnO 2 (111)-G, respectively) to systematically probe the facet effect in catalyzing bidirectional Li-S chemistry. [143] Deposition and dissociation processes of Li 2 S were investigated by potentiostatic discharge at 2.05 V and charge at 2.35 V, respectively. It is worth noting that SnO 2 (332)-G can contribute to higher Li 2 S nucleation and decomposition capacity than SnO 2 (111)-G and G, manifesting that SnO 2 (332)-G can promote the kinetics of both SRR and SER process (Figure 6g,h).…”

“…j) Decomposition energy barriers of Li 2 S on SnO 2 (332) and SnO 2(111) facets. (g-j) Reproduced with permission [143]. Copyright 2021, Wiley-VCH.…”

Atomic surface modification strategy ofMXenematerials forhigh‐performancemetal sulfur batteries

“…(c) Ion intercalation cause volumetric expansion, which results in structural deactivation 51 . Therefore, numerous carbonaceous substrates as hosts like microporous carbon, carbon nanotubes (CNTs), transition metal carbide and MXene get great attention because of the large surface area and high conductivity 52‐54 . However, the interaction between some carbonaceous hosts and polysulfides is weak, slowing down the diffusion of polysulfides ineffectively.…”

Manganese–nickel bimetallic oxide electrocatalyzing redox reactions of lithium polysulfides in lithium–sulfur batteries

“…That is, one component is for LiPS capture and the other is for catalyzing LiPS conversion. 16,17 Over the past few years, researchers have proposed some catalysts as the substrate in sulfur cathodes 18–20 or polypropylene (PP) separators 21–23 so as to accelerate the liquid–solid conversion kinetics, materials such as metal oxides, 24–26 metal sulfides, 21,27 metal nitrides 20,28 and metal selenides. 29,30 Manganic oxides have been proven to strongly adsorb LiPS, both experimentally and theoretically.…”