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Liquid-phase shear exfoliation (LPSE) is a potential method of large-scale production of good-quality graphene. Obtaining few-layer (<10) graphene with large lateral sizes and high yields remains a challenging issue. Here, we report an improved LPSE processing method involving the addition of mica plates, which serve as bifunctional agents. With the addition of 100 g L−1 of mica, the LPSE (9000 rpm/0.24 mm/1 h) of expanded graphite offers ∼100% few-layer graphene with average lateral sizes (ALSs) of ∼2.8 μm and yields of up to 27% (the highest ever reported). The graphene produced by LPSE without any additives, however, contains only ∼77% few-layer nanosheets, and has ALSs of ∼1.3 μm and yields of 8%. Significantly, the addition of SiO2 microspheres as a comparison has almost no influence on the LPSE. The mica plates control the vector of fluids in LPSE and guide the oriented arrangement of the layered materials (e.g., expanded graphite), leading to significantly improved LPSE efficiency. 2D transition metal dichalcogenides (TMDs) with improved yields were also successfully prepared using LPSE with the addition of mica. [ABSTRACT FROM AUTHOR]

Li metal has been regarded as one of the promising anode materials of the future due to its high specific capacity and low redox potential. To guarantee its safety and take full advantage of the capacity of Li metal batteries, it is important to understand the growth location, deposition uniformity, and degree of compactness of lithium metal deposition in the anode area during the operation of Li metal batteries. However, no research has been reported on the monitoring of lithium plating within the anode structure at the micro-level. Herein, we propose a new concept for the real-time monitoring of Li metal growth and the early surveillance of Li dendrites, which was demonstrated by simply adopting an alternating dielectric/conductive lamella structure. Within our alternated carbon nanofiber (CNF) scaffold and polyimide (PI) film host (CNF–PI host), the dielectric PI layer can block the direct electron transportation pathway between adjacent conductive CNF frameworks, thus guiding the Li metal plating in a more desirable stepwise "bottom-up" manner. The Li growth position could be detected in real time by monitoring the voltage between each conductive CNF layer and the counter electrode. And the Li deposition capacity inside each layer of CNF was further obtained, which reflected the stability of the Li deposition process. Meanwhile, due to the optimized Li deposition manner, a composite Li anode with this functional host shows excellent electrochemical performance. The full cell based on this functional Li metal anode with a LiNi0.8Co0.1Mn0.1O2 cathode shows excellent cycling stability under both a high current density of 3.6 mA cm−2 (1C rate) and areal capacity of 3.18 mA h cm−2. [ABSTRACT FROM AUTHOR]

Despite significant advances in cathode materials, developing high-performance anodes remains a key challenge for future pseudocapacitors. Fe 2 O 3 has been considered as a promising anode candidate due to its high theoretical capacitance, environmental benignity, and earth-abundant characteristics. However, the low electronic conductivity and poor cyclability of Fe 2 O 3 significantly limit its practical application. In this work, a 3D nickel-metalized carbon nanofiber network was developed to deposit an Fe 2 O 3 nanosheet anode. The nickel layer not only improved the electronic conductivity and the wettability of the 3D carbon substrate but also benefit the stability of the Fe 2 O 3 /carbon interfaces and the stress-release upon cycling. As a result, the newly designed Fe 2 O 3 anode composite exhibited a high areal capacitance of 1.80 F cm -2 at a high mass loading of 4.2 mg cm -1 and ultra-high capacitance retention of 85.1% after successive 100 000 cycles, outperformed most of the reported Fe 2 O 3 -based anode materials. Extended the interface metallization method to a MnO 2 cathode, excellent capacitance retention of 108.2% was reached after 26 000 cycles, suggesting a potentially broad application of such an interface-management method in elevating the stability of metal oxide materials in various pseudocapacitive energy storage devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)