Popularization of portable electronics and electric vehicles worldwide stimulates the development of energy storage devices, such as batteries and supercapacitors, toward higher power density and energy density, which significantly depends upon the advancement of new materials used in these devices. Moreover, energy storage materials play a key role in efficient, clean, and versatile use of energy, and are crucial for the exploitation of renewable energy. Therefore, energy storage materials cover a wide range of materials and have been receiving intensive attention from research and development to industrialization. In this Review, firstly a general introduction is given to several typical energy storage systems, including thermal, mechanical, electromagnetic, hydrogen, and electrochemical energy storage. Then the current status of high-performance hydrogen storage materials for on-board applications and electrochemical energy storage materials for lithium-ion batteries and supercapacitors is introduced in detail. The strategies for developing these advanced energy storage materials, including nanostructuring, nano-/microcombination, hybridization, pore-structure control, configuration design, surface modification, and composition optimization, are discussed. Finally, the future trends and prospects in the development of advanced energy storage materials are highlighted.

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Large-area monolayer WS2 is a desirable material for applications in next-generation electronics and optoelectronics. However, the chemical vapour deposition (CVD) with rigid and inert substrates for large-area sample growth suffers from a non-uniform number of layers, small domain size and many defects, and is not compatible with the fabrication process of flexible devices. Here we report the self-limited catalytic surface growth of uniform monolayer WS2 single crystals of millimetre size and large-area films by ambient-pressure CVD on Au. The weak interaction between the WS2 and Au enables the intact transfer of the monolayers to arbitrary substrates using the electrochemical bubbling method without sacrificing Au. The WS2 shows high crystal quality and optical and electrical properties comparable or superior to mechanically exfoliated samples. We also demonstrate the roll-to-roll/bubbling production of large-area flexible films of uniform monolayer, double-layer WS2 and WS2/graphene heterostructures, and batch fabrication of large-area flexible monolayer WS2 film transistor arrays.

Carbon nanotube (CNT)- and graphene (G)-based transparent conductive films (TCFs) are two promising alternatives for commonly-used indium tin oxide-based TCFs for future flexible optoelectronic devices. This review comprehensively summarizes recent progress in the fabrication, properties, modification, patterning, and integration of CNT- and G-TCFs into optoelectronic devices. Their potential applications and challenges in optoelectronic devices, such as organic photovoltaic cells, organic light emitting diodes and touch panels, are discussed in detail. More importantly, their key characteristics and advantages for use in these devices are compared. Despite many challenges, CNT- and G-TCFs have demonstrated great potential in various optoelectronic devices and have already been used for some products like touch panels of smartphones. This illustrates the significant opportunities for the industrial use of CNTs and graphene, and hence pushes nanoscience and nanotechnology one step towards practical applications.

Atomically thin hexagonal boron nitride (h-BN), as a graphene analogue, has attracted increasing interest because of many fascinating properties and a wide range of potential applications.However, it still remains a great challenge to synthesize high-quality h-BN with predetermined number of layers at a low cost. Here we reported the controlled growth of h-BN on polycrystalline Pt foils by low-cost ambient pressure chemical vapor deposition with ammonia borane as the precursor. Monolayer, bilayer and few-layer h-BN domains and large-area films were selectively obtained on Pt by simply changing the concentration of ammonia borane. Moreover, using a bubbling method, we have achieved the nondestructive transfer of h-BN from Pt to arbitrary substrates and the repeated use of the Pt for h-BN growth, which not only reduces environmental pollution but also decreases the production cost of h-BN. The monolayer and bilayer h-BN obtained are very uniform with high quality and smooth surfaces. In addition, we found that the optical band gap of h-BN increases with decreasing number of layers. The repeated growth of large-area, high-quality monolayer and bilayer h-BN films, together with the successful growth of graphene, opens up the possibility for creating various functional heterostructures for large-scale fabrication and integration of novel electronics.

The large polymer particle residue generated during the transfer process of graphene grown by chemical vapour deposition is a critical issue that limits its use in large-area thin-film devices such as organic light-emitting diodes. The available lighting areas of the graphene-based organic light-emitting diodes reported so far are usually <1 cm2. Here we report a transfer method using rosin as a support layer, whose weak interaction with graphene, good solubility and sufficient strength enable ultraclean and damage-free transfer. The transferred graphene has a low surface roughness with an occasional maximum residue height of about 15 nm and a uniform sheet resistance of 560 Ω per square with about 1% deviation over a large area. Such clean, damage-free graphene has produced the four-inch monolithic flexible graphene-based organic light-emitting diode with a high brightness of about 10,000 cd m−2 that can already satisfy the requirements for lighting sources and displays.

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Background Explore markers to predict the clinical outcomes of checkpoint inhibitors have high unmet needs. The following study investigates whether hematologic parameter such as systemic immune‐inflammation index (SII), neutrophil‐to‐lymphocyte ratio (NLR), platelet‐to‐lymphocyte ratio (PLR) is associated with nivolumab efficacy in advanced non‐small‐cell lung cancer (NSCLC). Methods Advanced/metastatic NSCLC patients treated with nivolumab monotherapy for second‐line or further‐line treatment at Jilin Cancer Hospital between March 2016 and July 2018 were enrolled in this retrospective study. The optimal cutoff values of SII, NLR, and PLR for predicting efficacy and prognosis were determined according to receiver operating characteristic (ROC) curve and the areas under the ROC curve. Progression‐free survival (PFS) and overall survival (OS) were calculated and compared using Kaplan‐Meier method and log‐rank test. Prognostic values of each variable were evaluated with univariate and multivariate Cox proportional hazard regression (PHR) analyses. Results A total of 44 patients with advanced NSCLC were included; the median age was 60 (range: 43‐74). The optimal cutoff value of SII/NLR/PLR predicted PFS and OS was 603.5, 3.07, and 144. Low SII, NLR, and PLR were associated with longer PFS (HR for SII = 0.34, 95%CI 0.15‐0.76, P = 0.006; HR for NLR = 0.46, 95%CI 0.22‐0.99, P = 0.048; HR for PLR = 0.39, 95%CI 0.17‐0.94, P = 0.025) and OS (HR for SII = 0.16, 95%CI 0.05‐0.51, P = 0.005; HR for NLR = 0.20, 95%CI 0.06‐0.62, P = 0.002; HR for PLR = 0.20, 95%CI 0.06‐0.73, P = 0.008). NLR ≤ 3.07, PLR ≤ 144, SII ≤ 603.5 were independently associated with longer PFS and OS. Conclusion The SII, NLR, and PLR are promising prognostic predictor for patients with metastatic NSCLC patients.