Metal hydroxide – a new stabilizer for the construction of sulfur/carbon composites as high-performance cathode materials for lithium–sulfur batteries

Abstract

Rational design and fabrication of advanced sulfur cathode is highly desirable for development of high performance lithium-sulfur (Li-S) batteries. Herein, we report Co(OH) 2 as a new stabilizer for the sulfur cathode by constructing cobalt hydroxidecovered sulfur/conductive carbon black (CCB) electrode with the help of thermal and hydrothermal treatments. In this composite (Co(OH) 2 @S/CCB), the sublimed sulfur is anchored in the CCB, followed by a uniform coating of Co(OH) 2 nanosheets. As cathode materials of lithium-sulfur batteries, the as-prepared Co(OH) 2 @S/CCB electrode exhibits remarkable electrochemical performances with a high capacity of 1026 mAh g -1 at 0.1 C (1 C=1675 mA g -1 ) and 829 mAh g -1 at 1 C. Moreover, it keeps high coulombic efficiencies above 97% after 200 cycles at 1 C, much higher than those of the S/CCB counterpart electrode (85%). After 200 cycles at 1 C, a high capacity retention of 71.2% is remained, better than that of the S/CCB electrode (20.2%). The enhanced performance is mainly due to Co(OH) 2 layer which helps to inhibit the shuttle diffusion of polysulfide, resulting in improved capacity retention and cycling life.

Heterogeneous/Homogeneous Mediators for High‐Energy‐Density Lithium–Sulfur Batteries: Progress and Prospects

“…The second strategy is to utilize oxides of transition metals with a myriad of possibilities to regulate the electronic structure, surface properties, and binding scenarios through d‐band engineering. These transition metal (hydro)oxides include Mn (MnO 2 , Mn 3 O 4 , and MnO), Fe (Fe 2 O 3 and Fe 3 O 4 ), Co (Co 3 O 4 , CoO, and Co(OH) 2 ), Ni (NiO and Ni(OH) x ), other transition metal‐based (VO 2 /V 2 O 5 , Nb 2 O 5 , etc Ni–Co/Fe LDH, and La 0.6 Sr 0.4 CoO 3− δ /Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3− δ perovskites) materials.…”

2D hybrid interlayer of electrochemically exfoliated graphene and Co(OH)2 nanosheet as a bi-functionalized polysulfide barrier for high-performance lithium–sulfur batteries

“…However, the weak interaction between non-polar carbons and polar polysulfides cannot fully suppress the diffusion of polysulfides in the organic electrolyte to lithium anode. The polar interlayers composed of such as oxides [28,29], sulfides [30,31], nitrides [32], polymer [33], hydroxide [34,35], and heteroatom-doped carbons [36,37], can greatly strengthen their interfacial interactions between polysulfides and interlayer, resulting in the enhancement of cyclabilities. However, high mass density loading of the polar materials would decrease energy densities of Li-S batteries.…”

Vertical‐Aligned Li2S–Graphene Encapsulated within a Carbon Shell as a Free‐Standing Cathode for Lithium–Sulfur Batteries

“…[1][2][3][4][5] However,t he commerciala pplication of Li-S batteries is still challenged by severals evere problems (e.g.,i nsulativity of element sulfur,l arge volumee xpansion of ca. [1][2][3][4][5] However,t he commerciala pplication of Li-S batteries is still challenged by severals evere problems (e.g.,i nsulativity of element sulfur,l arge volumee xpansion of ca.…”