Enhanced performance of alpha‐Fe ₂ O ₃ nanoparticles with optimized graphene coated layer as anodes for lithium‐ion batteries

Abstract

Summary A series of different α‐Fe2O3 nanoparticles composites containing different amounts of graphene coatings have been successfully prepared using a simple electrostatic self‐assembly (ESA) method. The structure and electrochemical properties of these α‐Fe2O3@graphene composites have been investigated. The α‐Fe2O3 nanoparticles composite containing 40 wt% graphene coating exhibits the highest specific capacity (385 mAh g−1) under 1000 mA g−1, resulting in superior cycle stability with no downward trend after 500 cycles. These results demonstrate that graphene coatings can be used to enhance the electrochemical properties and morphological stability of α‐Fe2O3 nanoparticles as anodic materials for high performance lithium‐ion batteries (LIBs). The low‐energy self‐assembly method employed in the paper has good potential for the broad‐scale preparation of other graphene‐modified materials because of its simplicity and the relatively low temperature conditions.

A novel flower‐like metal‐based oxides with cross‐linked networks for rapid lithium‐ion storage

“…In comparison, the ZnFe 2 O 4 hollow nanosphere sample can only deliver capacities of 632.1, 542.0, 453.7, 366.2, 280.5, and 208.8 mAh/g at rates of 0.1 to 0.2, 0.5, 1.0, 1.5, 2.0, and 3.0 A/g, 559.5, 422.0, 315.3, 223.3, 147.7, and 100.4 mAh/g for MnO 2 nanoplate anode as well. As can be seen, the as‐prepared ZnFe2O4@MnO2 is comparable with the metal oxides reported previously, as provided in Table .…”

Electrochemical performance of Mn 3 O 4 nanorods by N‐doped reduced graphene oxide using ultrasonic spray pyrolysis for lithium storage

“…In Figure 5A, the broad peak observed at 0.35-0.45 V in the first cathodic sweep of Mn-NrGO is assigned to the conversion of Mn 3 O 4 to MnO with the solid electrolyte interface (SEI) layer formation. 2,3,7,11,19,34 The intensely sharp peak at 0.14 V is a result of main reduction reaction (MnO ! metallic Mn).…”

“…Lithium ion batteries (LIBs), due to the high energy density, stable cycling ability, low self-discharge, and cell voltage are extensively dominant in practical applications, such as smartphones, tablet PCs, and electric vehicles (EVs). [1][2][3][4] Though, the commercial graphite anodes with low theoretical capacity (approximately 372 mAh/g) and rate capability do not fulfil the increasing energy requirements in terms of cost (approximately $150 per kWh based on Li-ion battery pack), drive range (approximately 300 miles), measured energy density (>100 Wh/kg), and safety for next-generation portable electrical devices. 2,[5][6][7] The researchers are focusing on In G. Kim and Faizan Ghani contribute equally to this study.…”

“…17,18 However, Mn 3 O 4 still has several issues, including (a) intrinsically poor electrical conductivity (10 −7 -10 −8 S/cm) that confines the rate capability, and (b) the severe volume change during the charge/discharge process. 3,8,9 These issues lead to the reduced electrochemical performance and structural instability. 11,12 Therefore, extensive studies with following approaches have been conducted to resolve these issues.…”

Solving Nafion poisoning of ORR catalysts with an accessible layer: designing a nanostructured core‐shell Pt/C catalyst via a one‐step self‐assembly for PEMFC

“…5,31 Coating a catalyst with a thin layer is always a popular idea to design a novel material, and most studies aimed to enhance their durability in PEMFC or even in lithium ion batteries. [32][33][34][35][36][37] Cheng et al stabilized Pt catalysts by coating a thin carbon layer derived from a common polymer made from soluble starch but at the expense of mass activity. 33 A nanostructured polyanilinedecorated Pt/C@PANI core-shell catalyst was prepared via a coating method to enhance the stability and ORR activity.…”