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H2 sensors have attracted considerable attention for safety warning of traditional industries and energy storing systems. This ZnO/rGO composite demonstrated excellent H2 sensing performances, good baseline stability and excellent selectivity.

Low initial Coulombic efficiency (ICE) is an important impediment to practical application of Li-rich layered oxides (LLOs), which is due to the irreversible oxygen release. It is generally considered that surface oxygen vacancies are conducive to the improvement of ICE of LLOs. To reveal the relation of oxygen vacancies and ICE, sample PLO (Li-Mn-Cr-O) and its treated product (TLO) are comprehensive investigated in this work. During the treated process, part of oxygen atoms return to original constructed vacancies. It makes oxygen vacancies in sample TLO much poorer than those in sample PLO, and induces the formation of Li-poor spinel-layered integrated structure. Electrochemical measurement indicates the ICE of sample PLO is only 80.8%, while sample TLO is almost full reversible with the ICE of ~97.1%. In term of high-energy X-ray diffraction, scanning transmission electron microscopy, X-ray photoelectron spectroscopy and synchrotron hard/soft X-ray absorption spectroscopy, we discover that the ICE is difficult to be improved significantly just by building oxygen vacancies. LLOs with high ICE not only have to construct suitable oxygen vacancies, but also require other components with Li-poor structure to stabilize oxygen. This work provides deep insight into the mechanism of high ICE, and will contribute to the design and development of LLOs for next-generation high-energy lithium-ion batteries.

Although lorlatinib, the third generation of echinoderm microtubule protein 4-anaplastic lymphoma kinase (EML4-ALK) tyrosine kinase inhibitor (TKI), overcame the previous generation ALK-TKIs' drug resistance problems, but the mechanism of lorlatinib resistance remained unclear. Furthermore, optimal chemotherapy for lorlatinib-resistant non-small cell lung cancer (NSCLC) patients was still unknown.A lorlatinib-resistant NSCLC cell line SNU-2535LR was generated by gradually increasing dose of lorlatinib to crizotinib-resistant cell line SNU-2535 in vitro. To study the resistance mechanism of SNU-2535LR cells, we applied CCK-8 assay to detect the sensitivity of crizotinib and the reverse effect of APR-246, a p53 activator, on lorlatinib-induced resistance and different chemotherapy drugs to SNU-2535LR cells. We also detected the expressions of EML4-ALK-related proteins of SNU-2535LR cells via western blot.Please confirm that author names have been identified correctly and are presented in the right order.Dear Editor: I have carefully confirmed that the author names have been identified correctly and are presented in right order.Thank you very much! Your sincerely BoXie RESULTS: The sensitivity of SNU-2535LR cells to lorlatinib was decreased significantly than that of SNU-2535 cells. EML4-ALK fusion was decreased both at protein level and DNA level in SNU-2535LR cells. More interesting, the crizotinib-resistant mutation ALK p.G1269A disappeared, while new TP53 mutation emerged in SNU-2535LR cells. APR-246 can reverse the lorlatinib resistance in SNU-2535LR cells, with a reversal index of 4.768. Compared with SNU-2535 cells, the sensitivity of SNU-2535LR cells to gemcitabine, docetaxel and paclitaxel was significantly increased (P 0.05), but decreased to cisplatin (P 0.05).This study demonstrated that the combination of p53 protein agonist and lorlatinib may provide a new therapeutic strategy for NSCLC patients with lorlatinib resistance and TP53 mutation. Furthermore, the results also provide guidance for selecting optimal chemo-regimens for NSCLC patients after ALK-TKIs failure.

Electro- and photocatalytic hydrogen evolution reaction (e-HER and p-HER) are two promising strategies to produce green hydrogen fuel from water. High intrinsic activity, sufficient active sites, fast charge-transfer capacity, and good optoelectronic properties must be taken into consideration simultaneously in pursuit of an ideal bifunctional catalyst. Here, platinum atomic clusters embedded in defects of TiO2 nanocrystals/graphene nanosheets (Pt-T/G) are reported as a bifunctional catalyst for electro- and photocatalytic hydrogen evolution reaction (e-HER and p-HER). High activity is delivered due to the charge transfer from the other part of the catalyst to the active center (Pt2-O4-Tix), decreasing the activation energy of the rate-limiting step, which is revealed by synchrotron X-ray absorption spectroscopy, photoelectrochemical measurements, and simulated calculations. In regard to e-HER, it outperforms the commercial 20 wt % Pt/C catalyst by a factor of 17.5 on Pt mass basis, allowing for a 93% reduction in Pt loadings. In regard to p-HER, it achieves photocatalytic efficiency (686.8 μmol h-1) without any attenuation in 9 h.

As one of the dominant configurations, platinum (Pt) single atomic catalysts (SACs) have pushed the performance of the hydrogen evolution reaction (HER) to an unprecedented level due to the maximiz...

Owing to the excellent abundance and availability of sodium reserves, sodium ion batteries (NIBs) show great promise for meeting the material supply and cost demands of large-scale energy storage systems (ESSs) used for the application of renewable energy sources and smart grids. However, the cost advantages of stationary NIBs alone are not enough to ensure their commercial success. In this review, we summarize the emerging attractive characteristics of stationary NIBs, such as high-rate capability, all-climate operation, and full-battery recyclability. Together with inherent cost advantages, these merits have resulted in an excellent compatibility between stationary NIBs and large-scale ESSs that dictates their validity in practical applications. Representative electrode materials are highlighted to illustrate advances in corresponding features. The insights presented in this review can inspire further research interest into NIB design and serve as a guide for the application of NIBs in large-scale stationary energy storage.

The shuttle effect hinders the practical application of lithium-sulfur (Li-S) batteries due to the poor affinity between a substrate and Li polysulfides (LiPSs) and the sluggish transition of soluble LiPSs to insoluble Li 2 S or elemental S. Here, we report that Ni hexatomic clusters embedded in a nitrogen-doped three-dimensional (3D) graphene framework (Ni-N/G) possess stronger interaction with soluble polysulfides than that with insoluble polysulfides. The synthetic electrocatalyst deployed in the sulfur cathode plays a multifunctional role: (i) selectively adsorbing the polysulfides dissolved in the electrolyte, (ii) expediting the sluggish liquid-solid phase transformations at the active sites as electrocatalysts, and (iii) accelerating the kinetics of the electrochemical reaction of multielectron sulfur, thereby inhibiting the dissolution of LiPSs. The constructed S@Ni-N/G cathode delivers an areal capacity of 9.43 mAh cm -2 at 0.1 C at S loading of 6.8 mg cm -2 , and it exhibits a gravimetric capacity of 1104 mAh g -1 with a capacity fading rate of 0.045% per cycle over 50 cycles at 0.2 C at S loading of 2.0 mg cm -2 . This work opens a rational approach to achieve the selective adsorption and expediting of polysulfide transition for the performance enhancement of Li-S batteries.

Electronic structure of single-atom catalysts (SACs) is critical for bifunctional oxygen electrocatalysis by adjusting the binding energy in oxygen-containing intermediates. However, the regulation of electronic structure has always been a challenge to improve catalytic reactivity. Herein, by introducing a heterogenous metal, the electronic structure through a direct bonding interaction to the active center atom is effectively adjusted. Partial charge transfer between the two atoms optimizes the binding energy of intermediates and reducing the energy barrier of the catalytic reaction. Theoretical calculations confirm these effects and the uniform distribution of 3d orbitals, leading to the improvement of bifunctional oxygen electrocatalytic reactivity. Benefiting from these attributes, the as-constructed bifunctional catalyst enables outstanding electrocatalytic performances in both oxygen reduction and hydrogen oxidation in various energy storage systems. The generality and expandability of this strategy is demonstrated by further successful development of other dual-metal catalysts systems with various active metals.

The development of sodium-ion batteries (SIBs) is hindered by the rapid reduction in reversible capacity of carbon-based anode materials. Outside-in doping of carbon-based anodes has been extensively explored. Nickel and NiS2 particles embedded in nitrogen and sulfur codoped porous graphene can significantly improve the electrochemical performance. Herein a built-in heteroatom "self-doping" of albumen-derived graphene for sodium storage is reported. The built-in sulfur and nitrogen in albumen act as the doping source during the carbonization of proteins. The sulfur-rich proteins in albumen can also guide the doping and nucleation of nickel sulfide nanoparticles. Additionally, the porous architecture of the carbonized proteins is achieved through removable KCl/NaCl salts (medium) under high-temperature melting conditions. During the carbonization process, nitrogen can also reduce the carbonization temperature of thermally stable carbon materials. In this work, the NS-graphene delivered a specific capacity of 108.3 mAh g-1 after 800 cycles under a constant current density of 500 mA g-1 . In contrast, the Ni/NiS2 /NS-graphene maintained a specific capacity of 134.4 mAh g-1 ; thus the presence of Ni/NiS2 particles improved the electrochemical performance of the whole composite.

Silicon is known for high-capacity yet large-volume-change properties when used as lithium storage material. Polymeric binders substantially contribute to improving the cycling life and increasing areal capacity of silicon anode. Herein, a robust network binder (PG-c-ECH) via localized linking by small molecules is proposed to achieve stable cycling performance of silicon anode with high areal capacity. Peach gum (PG) is rich in abundant hydroxyl and carboxyl groups that conventionally ensure a strong binding affinity between the PG and Si. The epichlorohydrin (ECH) introduced as the short-chain chemical crosslinker further enhances the localized linking for the polymer chains. The resultant PG-c-ECH owns durable interfacial adhesion and outstanding mechanical properties to stabilize the structural integrity of Si anode.

Rechargeable lithium metal batteries are among the most versatile platforms for high energy electrochemical energy storage. Unfortunately, uncontrollable growth of lithium dendrite triggers serious safety hazards, low Coulombic efficiency, and short cycling life, impeding the commercial application of lithium metal anode in the advanced energy storage technology, such as lithium-air and lithium‑sulfur (Li S) batteries. Herein, Chitosan oligosaccharide (CSO), an abundant bioderived material was employed to guide uniform lithium deposition and growth. CSO offers three features simultaneously, polar functional groups (-OH and -NH2), natural porous structure, and abundant sources. CSO with a large number of polar groups has strong interactions with Li ions, which could guide the Li ions to form uniform Li deposition. Moreover, the porous structure of CSO could serve as a Li host to accommodate the huge volume change during Li plating and stripping process. Additionally, CSO is a low-cost, abundant, and nontoxic bioderived material, which is suitable for large-scale production of the CSO-Li anode. The proposed strong interactions of CSO with Li ions were confirmed by density functional theory calculations. As expected, the CSO modified electrode demonstrates an outstanding average Coulombic efficiency of over 98% for 600 cycles at a current density of 2 mA cm−2. And stable cycling performances were achieved in the CSO-Li/CSO-Li symmetrical cells. Moreover, when paired with the LiFePO4 cathode, Li4Ti5O12 anode, high-mass-loading LiNi0.5Co0.2Mn0.3O2 cathode, and S cathode, the cells using the CSO-Li anodes show the higher capacities and better cycling stabilities compared with those of the cells using the bare Li anodes.

Transition metal-nitrogen-carbon (M/N/C) catalysts, Fe/N/C in particular, with low cost, good tolerance to methanol and promising activity has great potential to replace Pt-based catalysts in oxygen reduction reaction (ORR). However, for metal atoms are easy to migrate and agglomerate during pyrolysis, it still remains a challenge to rationally design precursors to synthesize highly active M/N/C without significant agglomeration of metal sites. In this work, we propose a molecular-confinement strategy to synthesize sub-nano Fe/N/C catalysts by confinement [Fe(CN)6]3- in zeolitic imidazolate framework-8 (ZIF-8) crystals to minimize the agglomeration of Fe atoms during pyrolysis. The half-wave potential of the prepared sub-nano Fe/N/C is 40 mV superior to that of commercial 20% Pt/C in alkaline medium. Besides, it has electron transfer number close to 4.00, with below 0.5% H2O2 yield, excellent long-term stability with only −5 mV shifts after 10000 cycles, and superb methanol tolerance. When utilized in Zn-air batteries as the cathode, it exhibits better activity, stability, and higher specific capacity than that of Pt–RuO2/C, showing a good potential for air cathode.

There is always trade-off among the functions of active materials, conductive additives and polymer binders. The balance is broken due to the emerging of high energy density silicon anode with low conductivity and huge volume variations. Herein, we explored a bicomponent electrode system through partial carbonization of nature polymers to solve the dilemma. Along with the carbonization process, the hydrogen bonding sites are gradually reduced, however, the dispersion force increases due to the decrease of the surface tension. Meanwhile, the electronic conductivity increases ascribed to the electron delocalization over the chain and in the length of the poly-conjugation. The balance of the binding strength and conductivity is tailored through the control of carbonization temperature. The optimum carbonization condition was revealed at 250 °C in air atmosphere. The partially carbonized polymer acts as both binder and conductive additive for the Si anode. As expected, the carbonized binding system can cycle the silicon anode stably without any other conductive additives. This partial carbonization binder is feasible to scale up due to the facile heat treatment process, which provides a new strategy for designing next-generation high-capacity batteries.