JOURNAL OF POWER SOURCES
·
2018
·
IF 6.945
Bohong Chen,Zhongqing Jiang,Lingshan Zhou,Binglu Deng,Zhong-Jie Jiang,Jianlin Huang,Meilin Liu
A simple synthetic method is developed for the synthesis of CoS 2 /N, S-codoped graphene. The result shows the existence of a strong electronic coupling between CoS 2 and N, S-codoped graphene. The pyrrolic and pyridinic type nitrogen and S in the form of C-S-C in N, S-codoped graphene are found to be the anchoring sites of the CoS 2 nanoparticles . As a bifunctional catalyst , the CoS 2 /N, S-codoped graphene exhibits an oxygen reduction onset potential of 0.963 V vs. RHE and delivers an oxygen evolution overpotential of 393 mV at the current density of 10 mA cm −2 . Its oxygen reduction and evolution catalytic activities are comparable to those of the Pt/C and the state-of-art RuO 2 /C, respectively. Most impressively, the CoS 2 /N, S-codoped graphene exhibits a potential gap of 771 mV. This value is lower than those of most bifuntional catalysts reported, clearly indicating its potential use as the bifunctional catalyst to replace the noble-metal based catalysts for practical applications. Additionally, our results also suggest a great importance to prepare a single pure phase CoS 2 in improving the catalytic bifunctionality of the CoS 2 /N, S-codoped graphene. The primary Zn-air battery with CoS 2 /N, S-codoped graphene shows a higher discharge peak power density than that with Pt/C.
研究领域:
材料科学
·
电化学
·
催化化学
·
能源材料
·
纳米材料
✓ 已验证
DOI
高影响因子
Materials Today Physics
·
2024
·
IF 10
Yuxiang Tang,Yake Yuan,Yuxue Mo,Haotian Tang,Mianze Wei,Haiqing Zhou,Tian Sheng,Chunsheng Li,Yan Sun,Xiaolin Wei
Lithium-sulfur (Li–S) batteries with high theoretical specific capacity of 1675 mAh g −1 and energy density of 2600 Wh kg −1 are considered as a promising candidate for energy conversion and storage devices in future. However, some critical dilemmas such as low real energy density , high solubility of ether-based electrolytes and slow redox kinetics of long-chain polysulfides remain unsettled hindering their development. Here we design and propose a high-performance sulfur host material constructed by growing CoN/Co 9 S 8 nanoparticles enclosed in reduced graphene oxide (RGO) and Co 9 S 8 modified separator to enhance the electrochemical performance of Li–S batteries . The results of first principal calculations confirm that the calculated adsorption energies of Li 2 S 8 , Li 2 S 6 , Li 2 S 4 and Li 2 S 2 on the Co 9 S 8 (111) surface are lower than that of the CoN (111) surface, indicating that the Co 9 S 8 has stronger adsorbing effect with polysulfides . Furthermore, the catalytic effect in Li 2 S 6 symmetric batteries and the nucleation of the Li 2 S tests display that the CoN/Co 9 S 8 @RGO has a fast conversion reaction kinetics and catalytic effect of polysulfides , thereby inhibiting the leakage of the polysulfides. Consequently, the S@CoN/Co 9 S 8 @RGO cathode with Co 9 S 8 layer represents a high discharge capacity of 1367.7 mAh g −1 at 0.1C and a prolonged lifespan over 700 cycles at 1 C with an extremely low decay rate of 0.06 % per cycle and high cycling stability.
研究领域:
电化学
·
能源材料
·
纳米复合材料
·
储能技术
·
催化化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2024
·
IF 5.5
Zhi Liu,Ningning Chen,Wanying Guo,Yinshuang Pang,Nailu Shen,Hong Chen,Wanying Zhang,Feichang Feng,Jingxiang Zhao,Yanyu Liang
Carbon-based materials are commonly used as anodes for potassium-ion batteries due to their high conductivity and stable cycling performance. However, their practical application is greatly hindered by their low capacity. Herein, we introduce facile sulfur chemistry including thioether bonds and CoS₂ into a nitrogen-oxygen co-doped partially graphitized carbon skeleton (NOGC), while the extra reconfiguration process of carbon assists forming the CoS₂@R-NOGC composites. The reconfigured NOGC (R-NOGC), enriched with highly electronegative elements (N, O, S), significantly enhances the reversible potassium ion storage capacity. The ordered carbon structure provides more efficient ionic transport pathways, thereby improving K⁺ transport efficiency. Moreover, layered CoS₂ acts as additional ion transport channels and active sites, further enhancing ion mobility and storage capacity. R-NOGC also promotes the reconstruction and repair of the solid electrolyte interface (SEI) layer to form a more robust interface. As a result of the synergistic effect between R-NOGC and CoS₂, it exhibits excellent anode performance, including a high reversible capacity (314.0 mAh/g at 0.1 A/g) and long-term stability (250.3 mAh/g at 0.5 A/g after 1,000 cycles). This work presents a novel strategy for designing and synthesizing high-performance anode materials for potassium-ion batteries, significantly enhancing both capacity and cycling stability.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
电池技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）