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The only way for commercial application of Li−air batteries with open structure is to receive O2 from ambient air. Nevertheless, H2O-containing ambient air easily induces Li passivation/dendrites and electrolyte decomposition. Apart from above issues, volatilization and leakage of organic liquid electrolytes and relatively infinite dimension variation of metallic Li also seriously discount performance of Li−air batteries. Herein, Li coating polythiophene-derived (S-doped) carbon fiber-based electrode (Li/SC) is prepared by simple rolling method and then in situ coated with deep eutectic solvent-based polymer electrolyte (DES-PE), which are further applied as anode and electrolyte of Li−air battery, respectively. Theoretical/experimental data suggest that SC skeleton possess excellent lithiophilicity/stability which restrain dendritic Li formation and reduce electrode structure damage over cycles. Furthermore, DES-PE not only possesses high ionic conductivity (1.19*10−3 S cm−1, 30 °C), wide electrochemical window (5.0 V), no-leakage and excellent interfacial compatibility, but also combine with SC framework to greatly reduce Li passivation induced by ambient air. Hence, DES-PE@Li/SC based Li−air battery could exhibit extra-large capacity of 15,310 mAh g−1 at 100 mA g−1, high-capacity retention even under high current (11,896 mAh g−1 at 500 mA g−1) and extra-long cycling life up to 300 cycles under fixed capacity. This result provides enlightment for the advancement of Li−air batteries.

Lithium (Li)-O2 batteries have triggered worldwide interest due to their ultrahigh theoretical energy density. However, it is a long shot for the grand-scale applications of Li-O2 battery at current stage owing to its significant polarization, inferior cycling life, and irreversible decomposition of Li2O2. Herein, a facile way of preparing the highly dispersed Co-based nanoparticles encapsulated into porous N-doping carbon polyhedral with the low content of Ru modification (LRu@HDCo-NC) is explored through the pyrolysis of Co/Zn based zeolitic imidazole frameworks (ZIFs) containing Ru-based ligands. Even with the very small amount of Ru introduction (1.8%), LRu@HDCo-NC still exhibits the superior oxygen evolution reaction/oxygen reduction reaction (OER/ORR) performance and also inhibits side reactions in Li-O2 battery because of the abundant pores, plentiful surface N heteroatoms, and highly dispersed metal-based sites which are induced by the volatilization of Zn, and conductive/stable carbon skeleton derived from ZIFs. When applied in Li-O2 batteries, LRu@HDCo-NC cathode delivers a high discharge capacity of 15,973 mAh·g−1 at 200 mA·g−1, good capacity retention at higher rate (12,362 mAh·g−1 at 500 mA·g−1) and outstanding stability for > 300 cycles with low voltage polarization of < 2.3 V under a cut-off capacity of 1,000 mAh·g−1 at 500 mA·g−1. More critically, a series of ex situ and in situ characterization technologies disclose that the LRu@HDCo-NC cathodes can effectively promote the reversible reactions in Li-O2 batteries.

Polymer based on norbornene was synthesized via ring-opening metathesis polymerization with norbornene possessed the advantages of easily modified molecular architectures, simple and controllable polymerization method, and great chemical stability. Novel Aquivion-based hybrid membranes were prepared by introducing polymer based on norbornene to Aquivion ionomers with short side chain. The resistance of Aquivion/PAN-10% hybrid membrane was the lowest among them due to the formation of hydrogen bonds between “acid-base” pairs. At the same time, all Aquivion-based hybrid membranes in this work possess excellent VO2+ permeability owing to the ionic crosslinking and Donnan effect. The Aquivion/PAN-2.5% hybrid membranes can still last for 31 h above 0.8 V because of the low VO2+ permeability. And Aquivion/PAN-2.5% hybrid membranes also exhibited more excellent Coulombic efficiency than Aquivion/PAN-5% hybrid membranes and Aquivion/PAN-10% hybrid membranes. The voltage efficiency of Aquivion/PAN-10% hybrid membranes was higher than that of Aquivion/PAN-2.5%. Aquivion/PAN-2.5% possesses an energy efficiency of 73.02% at the current density of 160 mA·cm−2. The Aquivion-based hybrid membranes possess excellent ion conductivity due to the formation of hydrogen bonds between “acid-base” pairs and low VO2+ permeability owing to the ionic crosslinking and Donnan effect.

A Zn-containing graphite carbon (Zn-GC) with uniform Zn metal sites and hierarchical pore structure was obtained by pyrolysis of Zn-based metal organic framework (MOF). Zn-GC exhibited excellent adsorption capacity and reproducibility for formaldehyde. The adsorption capacity of Zn-GC was 736 times that of commercial activated carbon and 5.6 times that of ZSM-5 adsorbents. The characterization and experimental results showed that the surface chemical characteristics of the adsorption material play an important role in the adsorption performance. The superior performance was attributed to Zn metal sites and oxygen-containing functional groups on the MOF derivative as well as hierarchical pore structure. The material showed a great potential in the field of organic pollutant removal.

Because of the advantages of high theoretical capacity, low cost, and environmental friendliness, lithium–sulfur (Li–S) batteries have attracted wide attention as promising energy storage system fo...

Rechargeable Li–O2 batteries have attracted worldwide attention due to their super-high energy density. However, there are still many critical challenges for Li–O2 batteries, such as huge overpotential caused by sluggish oxygen reduction/evolution reaction (ORR/OER) kinetics, and inferior cycle life derived from severe side reactions. Designing highly efficient cathode catalysts should be a good choice for Li–O2 batteries to solve the above problems. Herein, we developed Ir-coated Co nanoparticles confined into highly porous N-doped carbon nanocubes grafted with carbon nanotubes (Ir–Co/HP-NC/CNT) through carbonization of the Co/Zn–zeolitic imidazolate framework (ZIF) and the subsequent Ir-coating. Introduction of Zn into the ZIF precursor not only makes Ir–Co/HP-NC/CNT have high porosity that can promote ion/electron transfer, but also improves the surface content of pyridinic/graphitic N and CoxN phases which accelerate ORR/OER kinetics. Moreover, theoretical calculation/experimental results further confirm that the synergy between the Ir-coating and Co/HP-NC/CNT can effectively alleviate undesired parasitic reactions and also enhance reversibility in Li–O2 batteries by adjusting Li2O2 formation. As a result, Ir–Co/HP-NC/CNT based Li–O2 batteries show a super-high discharge capacity of 13 200 mA h g−1 at 100 mA g−1 and a very long cycling life up to 320 cycles at 500 mA g−1 with a fixed capacity of 1000 mA h g−1. Importantly, we have also designed large-size bulk-shaped Li–air batteries with Ir–Co/HP-NC/CNT cathodes that exhibit good performance even under bending conditions and effectively power practical electronic devices.

High-loading sulfur electrodes play a crucial role in the practical application of Li–S batteries. However, the poor mechanical stability and sluggish Li-ion conduction severely hinder the cycling stability and rate property of high-loading sulfur electrodes. PVDF binder has been widely used in Li–S batteries, while the coating process using PVDF binder requires toxic and expensive NMP solvent and the poor mechanical property of PVDF binder makes it incompetent as the binder for high-loading Li–S batteries. Herein, we use strong-affinity alginic acid (Alg) and high-wettability, high-modulus isosorbide (IS) to produce an environmentally friendly c-Alg-IS network binder via a condensation reaction for a high-loading sulfur electrode. As a result, a Li–S battery with a c-Alg-IS binder showed dramatically improved cycling stability and rate performance under high sulfur loading; especially, when the sulfur loading increases to 9.1 mg cm−2, the Li–S battery exhibits a stable cycling life of 60 cycles and high areal capacity of 7.2 mA h cm−2 at 2.4 mA cm−2. This work provides a simple and effective strategy to address the issues of poor cycling stability and rate property of high-loading Li–S batteries.

NC@Co-HPNC is synthesized, which exhibits a superior ORR/OER performance in acid/base solution. Hence, acid-base dual-electrolyte-based Zn-air batteries using NC@Co-HPNC reveal a long cycling life and a super-high voltage (2.1 V).

Designing the highly catalytic activity and durable bifunctional catalysts toward oxygen reduction/evolution reaction (ORR/OER) is paramount for metal–air batteries. Metal–organic frameworks (MOFs)-based materials have attracted a great deal of attention as the potential candidate for effectively catalyzing ORR/OER due to their adjustable composition and porous structure. Herein, we first introduce the Mn species into zeolitic-imidazole frameworks (ZIFs) and then further pyrolyze the Mn-containing bimetallic ZIFs to synthesize core-shell-structured Co@Co4N nanoparticles embedded into MnO-modified porous N-doped carbon nanocubes (Co@Co4N/MnO NC). Co@Co4N/MnO NC exhibits the outstanding catalytic activity toward ORR and OER which is attributed to its abundant pyridinic/graphitic N and Co4N, the optimized content of MnO species, highly dispersed catalytic sites and porous carbon matrix. As a result, the Co@Co4N/MnO NC-based Zn–air battery exhibits enhanced performances, including the high discharge capacity (762 mAh gZn−1), large power density (200.5 mW cm−2), stable potential profile over 72 h, low overpotential ( NC cathode-based Zn–air batteries are also designed which exhibit the superb electrochemical properties at different bending/twisting conditions.

In situ polymerization system can provide a compact and compatible interface with minimum polymer electrolyte, which is imperative to address the bottleneck of notorious solid–solid interface issue...

Inspired by the strong adhesion of mussels, a super-hydrophobic sponge was designed and prepared by a simple and inexpensive one-pot solution immersion method. The prepared superhydrophobic sponge can not only efficiently separate the oil–water mixture, more importantly, but also remove volatile organic compounds in the atmospheric environment. Polydopamine (PDA) enables polydivinylbenzene (PDVB) particles to be firmly and tightly attached to the melamine sponge skeleton, thereby making the hydrophilic sponge superhydrophobic and providing adsorption sites for volatile organic compounds in the air. The synergy enables the sponge/PDA/PDVB to quickly adsorb oils and organic substances, and it has high stability and capacity even after 20 cycles. In addition, superhydrophobic sponges can still perform outstanding adsorption performance even under highly acidic and alkaline environments. Meanwhile, the static adsorption capacity of the sponge/PDA/PDVB for gaseous toluene is 5.7 times that of activated carbon. Compared with pure PDVB, the super-hydrophobic sponge in the dynamic experiment has a penetration time increased from 6 to 390 min, which is 65 times longer than that of the PDVB, and the adsorption performance has been greatly improved. Therefore, our strategy may achieve a new effect, which can quickly and easily separate oil–water mixtures and remove volatile gaseous pollutants, and it can provide potential options for practical applications

Nonflammable functional electrolytes with remarkably interfacial compatibility toward both lithium anodes and high-voltage cathodes are considered as the ultimate pursuit for rechargeable lithium m...

The fast electron–hole recombination and low light utilization are two significant constraints to hinder the development of photocatalysis technology. Particularly, properly engineered heterojunction photocatalysts exhibit superior photoactivity because of spatial separation of photoinduced electron–hole pairs. Therefore, we prepared a heterojunction of zinc carbonate and zinc oxide by calcining precursor at 350 °C for 2 h. The as-prepared photocatalysts were obtained via a facile method and possessed promising photocatalytic activity for NO oxidation under UV light irradiation; the NO removal efficiency of heterojunction (42%) was better than that of pristine zinc oxide (28%) and precursor; the composites still maintained 88% activity after five cycles. Some relevant physicochemical properties were delicately investigated to elucidate that heterojunction can remarkably suppress the recombination of the electron–hole pairs, and promote the carriers transforming to activity species, which can participate in the redox reaction occurring on the surface of photocatalysts. More importantly, electron spin resonance measurement integrated with in situ DRIFTS spectra was applied to intuitively and dynamically monitor the reaction process and uncover the promotion mechanism. Finally, we believe that the synthesis strategy and mechanism analysis would provide guidance for understanding the gas-phase reaction.

Acids play a vital role in the controlled synthesis of parallel MnO2; the appropriate acid groups with highest oxidation state have no effect on the parallel structure, but acid groups with reducibility can promote its formation. Importantly, excess H+ also can serve as a medium for the transformation of parallel δ-MnO2 to needle-like α-MnO2. However, this process can be hindered by adding K+. Besides, the increased Mn3O4 from the pre-calcined templates can give rise to a selective growth of parallel δ-MnO2 and exhibit good cycle stability with 114% retention of initial specific capacitance after 10 000 cycles.

To obtain high energy density, it is crucial to fabricate high-loading electrodes, which is severely hindered by their mechanical degeneration. Furthermore, a general strategy with low cost, eco-friendliness, and facile operability is urgently required for wide application. Herein, a novel 3D network binder with an efficient damper is proposed via thermal condensation of polyacrylic acid and xanthan gum (c-PAA-XG), in which the covalent crosslinking provides robust mechanical strength to withstand the mechanical degeneration. Meanwhile, due to abundant dynamic intermolecular hydrogen bonds and molecular chain weaving, the double-helix-structure XG can partly deform and self-assemble and act as a high-efficiency damper to protect the network binder from fracture when large impulse occurs under high loading. Consequently, a wide range of ultrahigh-loading electrodes can be successfully achieved through simply applying this c-PAA-XG binder with traditional doctor blade coating technology on planar current collector. In particular, for the nano/micro-Si/C anode with a high loading of 18.3 mg cm−2, an ultrahigh reversible areal capacity of 27.7 mA h cm−2 can be delivered. Reaction kinetics investigations suggest that the charge–discharge process of the Si/C electrode is dominated by a capacitive-controlled behavior, resulting in fast storage/release of Li+ in high-loading electrodes. Furthermore, the c-PAA-XG binder has the advantages of low cost, eco-friendliness, and water-solubility, resulting in a sustainable electrode fabrication.

Li-based reduced (r)GO-Ni (Li/rGO-Ni) was prepared by a thermal-infusion method. Li/rGO-Ni based symmetric cells have high cycling stability and small voltage hysteresis at various current densities. Furthermore, the Li/rGO-Ni based Li-O2 batteries exhibit good performances.

Doping heteroatoms in photocatalyst is an effective strategy to signally enhance the photocatalytic activity. Herein, we have favorably fabricated the carbonate doped Bi2MoO6 via a facile one-pot solvothermal method, which was verified by structure and constituent characterization analysis. In addition, the NO removal efficiency of carbonate-intercalated Bi2MoO6 is ~34%, far-exceeding that of the pure Bi2MoO6 (~13%), whilst exhibits a good stability and durability, owing to that the dopants could modulate the electron states of the Bi2MoO6, thus stimulating charge separation and migration, incenting transformation of reactive oxygen species and facilitating reactants activation, which are synthetically investigated by experimental characterization coupled with DFT calculation. Significantly, the in situ DRIFTS measurement was employed to dynamic monitor the NO oxidation process and clarify the photocatalytic mechanism under visible light irradiation. This work provides an efficient strategy to design photocatalysts with tunable motivating charge conversion and reactants activation towards NO photooxidation.

Due to the capability of CO2 uptake and the high theoretical energy density, Li–CO2 batteries have attracted a great deal of attention as a novel and promising energy storage system which is based on the reversible reaction between lithium and CO2. However, the insulating Li2CO3 formed upon the discharge process, which is difficult to be decomposed during recharge process due to the lack of effective cathode catalyst, leads to the poor cycling performance and huge overpotential of the Li–CO2 batteries. In this work, the Ru nanosheets were directly grown on one side of the three-dimensional nickel foam through a galvanic replacement reaction to form the Ru/Ni electrode, which was further used in the Li–CO2 batteries. The highly dispersed Ru nanosheets in the Ru/Ni cathode effectively promote the decomposition of discharge product Li2CO3 and thus reduce the charge overpotential. Moreover, the typical porous and binder-free Ru/Ni electrode not only has a sturdy construction to suppress the side reaction in the Li–CO2 batteries, but also enables the rapid permeation of CO2 and electrolyte/electron into the active sites of the Ru/Ni electrode. As a result, the Ru/Ni cathode-based Li–CO2 battery exhibits the superior discharge capacity (9502 mAh g−1), good coulombic efficiency (95.4%) and excellent rate performance (3177 mAh g−1 at 500 mA g−1) at the full discharge/charge condition. When operated at the limited capacity of 1000 mAh g−1, this cell can run for over 100 cycles with the charge potential below 4.1 V. The findings provide a snapshot towards improving the reversibility of Li–CO2 batteries by designing the binder-free stable cathodes.

Aim Autophagy is a self-protective process, and it confers cancer cells resistance against radio-chemotherapeutics. To induce cancer cell death, a series of compounds of 3-((4-((7-chloroquinolin-4-yl)amino)butyl)amino)-7-substituted benzo[e][1,2,4]triazine 1-oxide or CQBTO containing two critical chemical groups were designed and synthesized. One compound, benzo[e][1,2,4]triazine 1-oxide, yielded free radicals to trigger autophagy, and the other one, chloroquine (CQ), was an inhibitor of autophagy. We hypothesized that the compounds could kill cancer cells effectively by inducing incomplete autophagy. Methods In vitro cultured non-small cell lung carcinoma cells and primary lung tumors in mice in vivo were used to test the lethal effects of CQBTO on cancer cells and toxicity to normal tissues. Cell viability was examined using the CCK8 assay. Genomic instability was determined with the cytochalasin B-blocked micronucleus assay. Cell cycle distribution was analyzed by propidium iodide staining and flow cytometry. Western blotting and immunofluorescence were used to detect the induction and localization of LC3, a biomarker for autophagy. Results Compared with CQ, three CQBTO compounds were lethal to lung cancer cells, and CQBTO-3 was the most effective. The LD50 for CQBTO-3 was 21 μΜ in A549 cells and 21.5 μΜ in Calu-1 cells, which was lower than that of CQBTO-2 or CQBTO-1. Induction of LC3 foci and an increase in the LC3II/LC3I ratio demonstrated the induction of autophagy by CQBTO-3 in A549 cells, whereas no obvious micronuclei or cell cycle arrest was observed. No detectable toxicity to normal mice was observed. CQBTO-3 improved the quality of mouse life, reduced the number and size of existing tumors, and suppressed tumor formation. Conclusion CQBTO-3 is a potential chemical compound for lung cancer treatment.

Heterojunction photocatalysts, which can alleviate the low carrier separation efficiency and insufficient light absorption capacity of a single catalyst, have received widespread attention. However, the specific interfacial structure of the heterojunction and its effect on the photocatalytic reaction is still unclear. Herein, a battery of zinc oxide/zinc sulfide (ZnO@ZnS) heterojunction microspheres with different degrees of sulfuration were successfully constructed via a facile hydrothermal method. The as-prepared photocatalysts shown decent aerobic nitric oxide (NO) oxidation performance under visible light irradiation, and the results of various characterization techniques illustrated that the superior photoactivity could be ascribed to the spatial separation of photoinduced electron-hole pairs due to the synergy of the internal electric field and the band offset. More importantly, density functional theory (DFT) calculations revealed that the heterojunction interface can significantly promote the generation of reactive oxygen species (ROS) and NO+ reaction intermediates and thus accelerate the photocatalytic reaction. Finally, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) technology was used to time-dependently monitor the NO oxidation process, revealing the photocatalytic mechanism. This work investigated the role of the heterojunction interface in the gas-phase catalytic reaction, broadening the practical application of the ZnO@ZnS heterojunction.

N,N′-Phenylenebis(5-tert-butylsalicylideneimine) is shown to be an effective single-component catalyst for the metal- and halide-free synthesis of cyclic carbonates from epoxides and carbon dioxide...

Designing efficient non-noble metal catalysts with good oxygen reduction activity is highly desirable but challenging. Herein, we demonstrate the synthesis of Fe-based carbon materials with multi active sites of Fe–Nx, Fe3O4 and Fe2C for oxygen reduction through facile pyrolysis of a Fe–porphyrin conjugated microporous polymer. The nanofiber structure of the polymer is retained with in situ Fe and N heteroatom doping and Fe3O4/Fe2C composite nanocrystals enchased in the walls of carbon fibers. Synergism between the N-doped carbon nanofibers and the in situ formed active sites of Fe–Nx, Fe2C and Fe3O4 facilitates the electrocatalytic performance of the as-synthesized catalysts. The catalyst obtained from 800 °C pyrolysis exhibits prominent oxygen reduction catalytic performance in 0.1 M KOH with an onset potential of 0.91 V, a half-wave potential of 0.81 V, and a small Tafel slope of 74 mV dec−1. Its limiting current density of −5.3 mA cm−2, excellent durability and resistance to methanol surpass the commercial 20% Pt/C under identical conditions. Thus, this work may provide a guideline for the design and synthesis of multi active nonprecious metal electrocatalysts for future fuel–cell applications.

Exploring highly efficient catalysts for the oxygen reduction/evolution reaction (ORR/OER) is very important in rechargeable Zn-air batteries. N-doped carbon coupled with transition metal-based species are among the most promising cathode catalysts for Zn-air batteries. However, the aggregation of metal-based sites during the synthetic/cycling process is a serious drawback of these catalysts. Herein, in situ encapsulation of ultra-small Co/Co4N nanoparticles into N-doping carbon nanotubes (N-CNTs) anchored on reduced GO (Co/Co4N@N-CNTs/rGO) has been achieved through pyrolyzing a core-shell-structured ZIF-8@ZIF-67-modified GO (ZIF-8@ZIF-67/GO) precursor; the nanoparticles have been further applied as a bifunctional catalyst in Zn-air batteries. Benefitting from its uniform dispersion of Co-based particles, close contact of Co/Co4N species and N-CNTs, and high N content, Co/Co4N@N-CNTs/rGO shows outstanding catalytic activity/stability towards ORR and OER. Moreover, Zn volatilization and rGO introduction in Co/Co4N@N-CNTs/rGO can effectively promote the reactions of Zn-air cells. Hence, the Co/Co4N@N-CNTs/rGO-based conventional Zn-air battery exhibits a fantastic specific capacity of 783 mA h gZn-1, a continuous discharge platform over 6 days, a high-power density of ∼200 mW cm-2 and an ultra-long cycling life of 440 h with a small overpotential of ∼0.8 V. Moreover, a flexible Co/Co4N@N-CNTs/rGO-based Zn-air cell was also designed and revealed outstanding mechanical flexibility and good electrochemical performance, which suggests its potential application prospects in wearable electronic devices.

Herein, we firstly prepared Co-doped birnessite and Mn-FeOOH nanotubes by a simple hydrothermal process using a sacrificed template method. The doping ratio was adjusted by setting the molar ratios of Co and Mn in the preparing process. Both the Co-doped birnessite and Mn-FeOOH nanotubes exhibit ideal electrochemical properties, especially their excellent rate capability.

Because of the severe shuttle effect of polysulfides, achieving durable Li-S batteries is still a great challenge, especially under practical operation conditions including the high sulfur content, high loading, and high operation temperature. Herein, for the first time, low-cost, eco-friendly, and hydrophilic cellulose nanocrystals (CNCs) are proposed as a multifunctional polysulfide stopper for Li-S batteries with high performance. CNCs display an intrinsically high aspect ratio and a large surface area and contain a large amount of hydroxyl groups offering a facile platform for chemical interactions. Density functional theory calculations suggest that the electron-rich functional groups on CNCs deliver robust binding energies with polysulfides. In this work, CNCs not only firmly confine sulfur and polysulfides in the cathode as a robust binder, but also further hinder polysulfide shuttling to the Li anode as a polysulfide stopper on a separator. Consequently, the as-prepared Li-S batteries demonstrate outstanding cycling performance even under the conditions of high sulfur content of 90 wt % (63 wt % in the cathode), high loading of 8.5 mg cm-2, and high temperature of 60 °C. These results sufficiently demonstrate that CNCs have significant application potential in Li-S battery technologies.

Summary Low-temperature operation is a great challenge facing rechargeable batteries, and insufficient ionic conductivity and freezing of electrolyte are generally considered as the main reasons for this issue. Herein, an ethyl acetate-based electrolyte with a sufficient ionic conductivity of 0.2 mS cm −1 at the ultra-low temperature of −70°C is first used to fabricate intercalation compounds-based Li-ion batteries (LIBs) and an organic electrodes-based rechargeable battery, respectively, to clarify their low-temperature behavior. It is demonstrated that the LIBs cannot work at −70°C because of the sluggish desolvation of Li + . However, the rechargeable battery using organic electrodes can work well at such low temperature and retains ∼70% of capacity at room temperature, owing to the fast kinetics of charge storage on the surface groups or in the large interstitial space of organic solids. These results indicate a new way for developing low-temperature batteries.

Lithium–Oxygen (Li–O2) batteries have great potential for promising next generation battery, owing to their high theoretical energy density. However, this system still faces many problems such as poor cycling performance and low coulombic efficiency, which mainly stems from the parasitic side reactions on cathode, the decomposition of electrolyte and the corrosion of Li anode. Herein, a novel gel polymer electrolyte (GPE) containing the polymethyl methacrylate (PMMA) with high stability towards the superoxide molecules and ionic liquid (IL) with the non-volatility (PMMA/IL-GPE) is designed by ultra violet (UV) treatment. PMMA/IL-GPE not only possesses the excellent ion conductivity (0.92 mS cm−1), the wide voltage window (not be oxidized until > 4.7 V) and superior leakproof property, but also effectively protects Li anode from O2-attacking. Moreover, we have further applied electroplating strategy to synthesize the binder-free Ru-coating N, P co-doped cathode (Ru@NPC), which greatly reduce the side reaction of cathode and reduce the charging overpotential. Hence, the Ru@NPC based Li–O2 batteries using PMMA/IL-GPE show effectively improved discharge capacity (32793.5 mAh g−1). When operated at the limited capacity, this battery can run for over 120 cycles with the low charge overpotential of

The metallic Li electrode is considered as the most promising anode candidate for next-generation rechargeable batteries due to its super-high energy density. However, the safety and passivation issue, low coulombic efficiency and short cycle-life derived from uneven Li dendrites and an unstable solid electrolyte interphase (SEI) have hindered the practical application of Li metal batteries, especially Li–air batteries. Herein, we have synthesized Co4N-doped Co nanoparticles embedded into hollow nitrogen (N)-doped carbon nanocubes (Co/Co4N-NC) through the pyrolysis of a metal–organic framework (MOF), and further applied it as the Li plating matrix. The high content of lithiophilic Co4N, pyridinic and pyrrolic N species in Co/Co4N-NC can effectively ensure the uniform distribution of Li. In addition, the intercalation reaction in graphitized carbon coupled with electrodeposition reaction in the porous framework can further enhance the Li storage capacity of Co/Co4N-NC. Moreover, we have also demonstrated the formation of a stable SEI layer on the Co/Co4N-NC electrode during the Li plating process. Hence, the Co/Co4N-NC electrode can significantly suppress dendritic Li and shows a high coulombic efficiency of 98.5% over 300 cycles. More importantly, a Li–air battery using the lithiated Co/Co4N-NC electrode displays better cycle performance than a Li–air cell with a Li-anode in ambient air.

Layered MoS2 has been recognized as a promising low-cost alternative to Pt-based electrocatalysts towards the hydrogen evolution reaction (HER). Intensive interest has been mainly focused on designing MoS2 nanostructures with large amounts of active edge sites and fast charge transfer. Here we report the synthesis of vanadium and nitrogen co-doped MoS2 on reduced graphene oxide with new defect sites on the basal/edge planes and expanded interlayer spacing, which shows remarkable catalytic merits with an extremely low overpotential of 68 mV at 10 mA cm−2 and a Tafel slope of 41 mV dec−1. Its performance is superior to most current MoS2 electrocatalysts. In addition to the charge transfer benefits of the RGO substrate, the vanadium and nitrogen dopants trigger defect sites on the basal/edge planes, and an optimized electronic structure and expanded interlayer distance are also responsible for the enhancement in catalysis. This contribution may offer a potential way to design advanced MoS2 catalysts by modulating the defect sites and interlayer distance for efficient electrochemical water splitting.

Flexible Li–air batteries have been proposed as a potential power source for next-generation flexible electronics due to their super-high theoretical energy density. However, the safety problems derived from dendritic-deposition and high-activity of a Li anode and the leakage and volatilization of liquid electrolyte severely impede their practical application. Herein, we design a flexible belt-shaped Li–air battery with high stability and safety, which is constructed by using a reduced graphene oxide (rGO)/Li anode, gel polymer electrolyte containing LiI and 4 wt% SiO2 (4% SiO2–LiI-GPE). The rGO/Li anode shows lower mass density, better toughness and less dendrite growth compared with a pure Li anode. Additionally, 4% SiO2–LiI-GPE has a high ionic conductivity of 1.01 mS cm−1, flame-resistant polymer matrix, excellent protective effect on the Li anode and no-leakage properties. Furthermore, the synergy of the LiI and SiO2 additives promotes the decomposition of discharge products and improves the safety of the battery at the same time. As a result, this belt-shaped Li–air battery can steadily run for 100 cycles with a small average overpotential of ∼1.45 V in ambient air (relative humidity of 15%) under different mechanical deformations. Moreover, its voltage curves over operation could remain almost unchanged under a series of bending conditions.

The traditional oxygen reduction/evolution reaction (ORR/OER) catalysts are mainly noble metal-based materials, but their scarcity and instability impede their practical applications, especially in Zn–air batteries. Hence, identifying a bifunctional catalyst with low-cost and high-stability is very crucial for Zn–air batteries. Herein, we report a simple method to prepare core–shell-structured Co@Co3O4 nanoparticles encapsulated into N-doped carbon polyhedra by carbonization and controlled oxidation of metal–organic frameworks (MOFs), which are then applied as a bifunctional catalyst for Zn–air batteries. Using such a configuration, enhanced performances, including a high power density of ∼64 mW cm−2, a stable voltage profile over 80 h battery operation with four mechanical recharges, a small discharge/charge overpotential of ∼0.66 V and a long-life of 100 cycles for 200 h operation at 5 mA cm−2, have been achieved. These excellent performances can be attributed to abundant graphited carbon and CNTs, high N-doping, plentiful pores, the synergy between the semiconductive Co3O4-coating layer and the conductive Co bulk, and the uniform Co@Co3O4 nanoparticles in this catalyst which effectively improve electrical conductivity/ion transfer and further concertedly promote the catalytic activity towards the ORR/OER. Moreover, the belt-shaped polymer Zn–air battery with this catalyst also shows good electrochemical stability under different deformations.

Rechargeable Li–CO2 batteries have attracted extensive attentions since their excellent abilities of absorbing CO2 and delivering super-high energy density. Recently, many effective catalysts have been developed to improve the performance of Li–CO2 batteries, which nevertheless is still inhibited by problems derived from Li anodes and liquid electrolyte, such as Li dendrites and electrolyte leakage. In this work, we construct Li-ethylenediamine (LE) layer on Li (LE-Li) and use it to further react with tetraglyme in battery to obtain tetraglyme-based polymer electrolyte (TPE). The uniform LE layer coupled with in-situ formed TPE can not only restrain dendrite generation, Li-induced side reaction and corresponding passivation/pulverization, but also reduce interfacial impedance and enable battery work normally at bending condition. Therefore, the LE-Li electrode presents the more stable electrochemical property than the pure Li anode in symmetric battery. Additionally, the Li–CO2 battery using LE-Li/TPE displays high discharge capacity of 22873 mAh g−1 and good rate capability under full discharge/charge condition. When operated at cut-off capacity, this cell can steadily run for 104 cycles with a small overpotential of

High-energy-density Li-ion batteries are urgently demanded in the development of electric vehicles and smart power grids. Owing to the high theoretical capacity, silicon (Si) has been considered as one of the most promising anode materials for next-generation Li-ion batteries. However, Si anode materials undergo huge volume change during charge and discharge processes, which severely impairs the cycle stability of Si anodes. Herein, to stabilize the Si anodes, a low-cost and eco-friendly network binder coupling hardness with softness was designed through in-situ cross-linking of guar gum (GG) and carboxylated acrylonitrile-butadiene rubber (XNBR). The rigid and high-viscosity GG functions as a skeleton to withstand the expansion of Si active materials, and the elastic XNBR can effectively buffer the residual stress. The mass ratio of GG and XNBR was systematically studied to achieve superior cycling stability of Si anodes. Especially, the Si@X4G6 electrode shows excellent cycle stability, remaining a capacity of 1929 mAh g − 1 at 1000 mA g − 1 after 100 cycles. Interestingly, such an effective strategy not only works well in Si anodes but also does well in Si/C anodes and LiFePO4 cathodes.

The utilization of CO2 in Li-CO2 batteries is attracting extensive attention. However, the poor rechargeability and low applied current density have remained the Achilles' heel of this energy device. The gel polymer electrolyte (GPE), which is composed of a polymer matrix filled with tetraglyme-based liquid electrolyte, was used to fabricate a rechargeable Li-CO2 battery with a carbon nanotube-based gas electrode. The discharge product of Li2 CO3 formed in the GPE-based Li-CO2 battery exhibits a particle-shaped morphology with poor crystallinity, which is different from the contiguous polymer-like and crystalline discharge product in conventional Li-CO2 battery using a liquid electrolyte. Accordingly, the GPE-based battery shows much improved electrochemical performance. The achieved cycle life (60 cycles) and rate capability (maximum applied current density of 500 mA g-1 ) are much higher than most of previous reports, which points a new way to develop high-performance Li-CO2 batteries.

Metallic lithium (Li) is regarded as the ultimate anode for high-energy-density rechargeable batteries due to its highest theoretical capacity and most electronegative potential. However, there are serious challenges before practical application of Li metal batteries (e. g. Li–air batteries), including the dendritic Li formation and infinite variation of electrode dimension. Herein, nitrogen (N) and sulfur (S) co-doping carbon paper (NS-CP) is synthesized and further modified with a graphite-based layer (GL) by pencil-drawing. The as-prepared GL modified NS-CP (GL/NS-CP) is applied to pre-store Li through the heating-infusion method and Li-GL/NS-CP electrode is obtained. Experimental and theoretical results have demonstrated that N, S co-doping can effectively enhance the lithiophilicity of CP to ensure the uniform Li deposition. In addition, GL presents excellent Li wettability to rapidly syphon molten Li. Moreover, abundant pores in GL/NS-CP can accommodate enough Li to alleviate electrode volume change and lower local current density to restrain Li dendrites. Compared with pure Li anode, Li-GL/NS-CP electrode shows more stable voltage curves with lower overpotential (20 ​mV for 600 cycles). As a result, Li–air batteries with Li-GL/NS-CP anodes also exhibit the satisfying cycling life. These results have shed a new light on the development of Li anodes.

Recent studies have demonstrated that radiation activates in situ antitumor immunity and consequently induced a synergistic effect of radiotherapy and immunotherapy. However, studies related to radiation-induced changes in immune system of tumor-bearing mice are limited, which are of great significance to improve the efficacy of radioimmunotherapy. In this study, we first established a primary lung tumor mouse model using urethane. Then part of the right lung of the mouse was exposed to X-ray irradiation with a computed tomography–guided small animal irradiator and the changes of immune cells in both peripheral blood and spleen were determined by flow cytometry. Besides, the levels of both cytokines and immunoglobulins in mouse serum were detected by a protein chip. We found that B lymphocytes increased while CD8+T lymphocytes reduced significantly. Interleukin-3 (IL-3), IL-6, regulated upon activation, normally T-expressed, and presumably secreted factor (RANTES), and vascular endothelial growth factor (VEGF) were found to be decreased after tumor formation, and the similar results have also been observed with kappa, IgG3, IgE, IgM, and IgG2a. After irradiation, lower concentrations of IgD, kappa, and IgM were found in the serum. Our findings indicate that localized tumor irradiation caused some obvious changes like inhibiting the ability of innate immunity, and these changes may be useful in predicting prognosis.

Radioresistance is the major obstacle in the radiotherapy of the malignant melanoma. Thus, it is of importance to increase the radiosensitivity of melanoma cells. In the present study, the radioresistant melanoma cell line OCM-1 with inducible overexpression of Ras-related C3 botulinum toxin substrate 2 was established based on a radiation-inducible early growth response gene (Egr-1) promoter. The effects of Ras-related C3 botulinum toxin substrate 2 overexpression on the radiosensitivity of melanoma cells exposed to either X-rays or carbon ion beams were evaluated in cultured cells as well as xenograft tumor models. In addition, both reactive oxygen species yield and the NADPH oxidase activity were measured in the irradiated melanoma cells. It was found that the radiation-inducible overexpression of Ras-related C3 botulinum toxin substrate 2 sensitized the melanoma cells to both X-rays and carbon ion irradiation by enhancing the NADPH oxidase activity and the subsequent reactive oxygen species production. Besides, the overexpression of Ras-related C3 botulinum toxin substrate 2 enhanced the tumor-killing effect of radiotherapy in xenograft tumors significantly. The results of this study indicate that Ras-related C3 botulinum toxin substrate 2 is promising in increasing the radiosensitivity of melanoma cells, which provides experimental evidence and theoretical basis for clinical radiosensitization of the malignant melanoma.

Understanding and establishing a specific relationship between modified structures and photocatalytic reaction process has a profound significance for designing catalysts with preferable activity. In this study, we have favorably synthesized the bismuth oxyhalides (BiOClxBr1-x, 0 ≤ x ≤ 1) photocatalysts by utilizing the ethylene glycol assisted solvothermal method and the calcination procedure for photocatalytic nitric oxide oxidation. By regulating the halogen proportion in anions layer, the lattice strain has been induced in the structure, specifically the tensile strain in c axis. By virtue of in situ DRIFTS and DFT calculation, we found that the optimized surface reaction thermodynamic process should be the main factors response for prominent enhanced photocatalytic activity, rather than the light absorption and separation of carriers. The bismuth oxyhalides with Cl/Br ratios of 3:1 (BiOClxBr1-x-3:1) possess the lowest thermodynamic energy barrier for photocatalytic nitric oxide oxidation reaction, whilst both associative and dissociative reaction process exist in the initial elementary reaction about oxygen reduction. Finally, we develop a feasible strategy to depress thermodynamic energy barriers via tuning the ratio of halogen in anions layer and bringing the lattice strain, as well build relationship between the adjusted structures and surface reaction process.

Exploiting visible-light-responsive photocatalysts for highly-efficient water-splitting is a very promising way to achieve the renewable hydrogen energy. To this end, the rational manipulation on the composition and structure of semiconductor nanomaterials appears extremely necessary. Herein, we construct a unique hybrid consisting of P-doped CZ0.10S-0.5P porous nano-spheres coupled with Ni2P and reduced graphene oxide (rGO) cocatalysts (CZ0.10S-0.5P@Ni2P/rGO), which exhibits an outstanding performance for H2 evolution reaction (HER) under visible-light (λ > 420 nm) irradiation. Noticeably, the CZ0.10S-0.5P@2Ni2P/1.5rGO with 2 wt%-Ni2P and 1.5 wt%-rGO delivers an exceptional HER rate of 616.8 mmol∙h−1∙g−1 (the apparent quantum efficiency reaches 77.0% at 475 nm), outperforming that of Pt-loaded CZ0.10S-0.5P and the great majority of CdS-based composites reported previously. In addition, the CZ0.10S-0.5P@2Ni2P/1.5rGO composite also presents a steady H2 generation activity under prolonged irradiation. The superior photocatalytic property of CZ0.10S-0.5P@Ni2P/rGO could be associated with the abundant active sites provided by Ni2P, excellent visible-light absorption, and effective charge transfer and separation enabled by the Schottky junctions formed between CZ0.10S-0.5P and Ni2P/rGO. The findings indicated here could promote the design and manufacture of advanced semiconductor nanostructures for sustainable energy applications.

The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are traditionally carried out using noble metals (such as Pt) and metal oxides (such as RuO2 and IrO2) as catalysts, respectively. Nevertheless, several key issues such as high cost, poor stability, and detrimental environmental effects limit the catalytic activity of these noble metal- and metal oxide-based catalysts. Herein, we have designed and synthesized macroporous carbon nanofiber arrays by using a natural crab shell template. Subsequently, spinel MnCo2O4 nanoparticles were embedded into the nitrogen-doped macroporous carbon nanofiber arrays (NMCNAs) by a hydrothermal method. Accompanied by the good conductivity, large surface area and doping of nitrogen, the as-prepared MnCo2O4/NMCNA exhibited remarkable catalytic performance and outstanding stability for both ORR and OER in alkaline media. The macroporous superstructures play vital role in reducing the ion transport resistance and facilitating the diffusion of gaseous products (O2). Finally, rechargeable Zn–air batteries using the MnCo2O4/NMCNA catalyst displayed appreciably lower overpotentials, higher power density and better stability than commercial Pt/C, thus raising the prospect of functional low-cost, non-precious-metal bifunctional catalysts in metal–air batteries.

The Li–O2 battery is receiving much recent attention because of its superhigh theoretical energy density. However, its performance is limited by the irreversible formation/decomposition of Li2O2 on the cathode and the undesired electrolyte decomposition. In this work, low-cost three-dimensional ordered macroporous (3DOM) FePO4 is synthesized by using polystyrene (PS) spheres template in a facile experimental condition and applied as a high-efficiency catalyst for rechargeable Li–O2 batteries, including good rate performance, high specific capacity, and perfect cycling stability. The superior performances can be attributed to the unique structure of 3DOM FePO4 cathodes, which can provide an efficient buffer space for O2/Li2O2 conversion. In addition, it is demonstrated that the Li+ intercalation/deintercalation behavior of 3DOM FePO4 in ether-based electrolyte can contribute to capacity for Li–O2 batteries over cycling. As a result, when there is no O2 in the environment, the Li–O2 cell can also be operate...

Correction for ‘A lithium air battery with a lithiated Al–carbon anode’ by Ziyang Guo et al., Chem. Commun., 2015, 51, 676–678, DOI: 10.1039/C4CC07315K.