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The practical application of lithium-metal anodes in high-energy-density rechargeable lithium batteries is hindered by the uncontrolled growth of lithium dendrites and limited cycle life. An ether-based gel polymer electrolyte (GPE-H) is developed through in situ polymerization method, which has close contact with the electrode interface. Based on DFT calculations, it was confirmed that the cationic groups produced by polar solvent tris(1,1,1,3,3,3-hexafluoroisopropyl) (HFiP) initiate the ring-opening polymerization of DOL in the battery. As a result, GPE-H achieves considerable ionic conductivity (1.6 × 10 -3 S cm -1 ) at ambient temperature, high lithium-ion transference number ( t Li + > 0.6) and an electrochemical stability window as high as 4.5 V. GPE-H can achieve up to 800 h uniform lithium plating/stripping at a current density of 1.65 mA cm -2 in Li symmetrical batteries. Li-S and LiFePO 4 batteries using this GPE-H have long cycle performances at ambient temperature and high Coulomb efficiency (CE > 99.2%). From the above, in situ polymerized GPE-H electrolytes are promising candidates for high-energy-density rechargeable lithium batteries.

The density functional theory (DFT) method was applied to study the structural, electronic and surface properties of low-index Al 3 Ti intermetallic materials. The surface energies and electronic structures of those surfaces were also discussed in this study. The calculated surface energies of the low-index surfaces of Al 3 Ti indicated that nonstoichiometric (110) surface with Al termination was the most stable surface. On this basis, the oxygen adsorption behavior of the (110)-Al surface was further studied to clarify the antioxidant mechanism of Al 3 Ti intermetallic alloys. Various adsorption sites of oxygen atoms on the (110)-Al surface were considered to identify the most stable adsorption configurations. According to the calculation results of adsorption energies, it was found that stability was maximized when oxygen was adsorbed at the Al-Al bridge site. Meanwhile, a density of state study indicated that adsorption of oxygen on the (110)-Al surface preferred to bond with Al atoms rather than Ti atoms., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The composite cathode material of the conductive polymer polyaniline (PANI)-coated spinel structural LiNi 0.5 Mn 1.5 O 4 (LNMO) for high-voltage lithium-ion batteries has been successfully synthesized by an in situ chemical oxidation polymerization method. The electrode of the LNMO-PANI composite material shows superior rate capability and excellent cycling stability. A capacity of 123.4 mAh g -1 with the capacity retention of 99.7% can be maintained at 0.5C after 200 cycles in the voltage range of 3.0-4.95 V (vs Li/Li + ) at room temperature. Even with cycling at 5C, a capacity of 65.5 mAh g -1 can still be achieved. The PANI coating layer can not only reduce the dissolution of Ni and Mn from the LNMO cubic framework into the electrolyte during cycling, but also significantly improve the undesirable interfacial reactions between the cathode and electrolyte, and markedly increase the electrical conductivity of the electrode. At 55 °C, the LNMO-PANI composite material exhibits more superior cyclic performance than pristine, that is, the capacity retention of 94.5% at 0.5C after 100 cycles vs that of 13.0%. This study offers an effective strategy for suppressing the decomposition of an electrolyte under the highly oxidizing (>4.5 V) and elevated temperature conditions., Competing Interests: The authors declare no competing financial interest.

Evidence on the adverse effects of agricultural pesticide use by farmers under the actual field conditions on their peripheral nerve conduction in China is limited. This study was to investigate the association of agricultural pesticide use with the abnormalities of farmers' peripheral nerve conduction based on two rounds of conventional nerve conduction studies. The level of pesticide exposure was assessed by measuring total amount of pesticides used by farmers in 2012. The logistic and negative binomial regression analyses were performed on a cohort study of 218 farmers. Results show that agricultural use of neither glyphosate nor non-glyphosate herbicides was not found to induce the abnormalities of farmers' peripheral nerve conduction. However, agricultural use of organophosphorus compounds was significantly associated with increased risk of demylination disease of peripheral nerve conduction described by the reduced velocity. Moreover, the use of organonitrogen compounds by farmers would not only increase risk of demylination disease but axonal damages described by the reduced amplitude. By contrast, agricultural uses of organosulfur and pyrethroid compounds would not induce the abnormalities of farmers' peripheral nerve conduction. The findings demonstrated the importance of developing health-friendly pesticides to replace organophosphorus and organonitrogen insecticides and fungicides in China.

Metal oxides as anode materials for lithium storage suffer from poor cycling stability due to their conversion mechanisms. Here, we report an efficient biomimetic method to fabricate a conformal coating of conductive polymer on ZnFe 2 O 4 nanoparticles, which shows outstanding electrochemical performance as anode material for lithium storage. Polydopamine (PDA) film, a bionic ionic permeable film, was successfully coated on the surfaces of ZnFe 2 O 4 particles by the self-polymerization of dopamine in the presence of an alkaline buffer solution. The thickness of PDA coating layer was tunable by controlling the reaction time, and the obtained ZnFe 2 O 4 /PDA sample with 8 nm coating layer exhibited an outstanding electrochemical performance in terms of cycling stability and rate capability. ZnFe 2 O 4 /PDA composites delivered an initial discharge capacity of 2079 mAh g -1 at 1 A g -1 and showed a minimum capacity decay after 150 cycles. Importantly, the coating layer improved the rate capability of composites compared to that of its counterpart, the bare ZnFe 2 O 4 particle materials. The outstanding electrochemical performance was because of the buffering and protective effects of the PDA coating layer, which could be a general protection strategy for electrode materials in lithium-ion batteries., Competing Interests: The authors declare no competing financial interest.

The economic benefits of insect-resistant genetically modified (GM) crops have been well documented, but the impact of such crops and the consequent reduction in pesticide use on farmers' health remains largely unknown. Through the analysis of the data collected from the physical examination from farmers in China, we show that GM rice significantly reduces pesticide use and the resultant not only visible but also invisible adverse effects on farmers' neurological, hematological, and electrolyte system. Hence, the commercialization of GM rice is expected to improve the health of farmers in developing countries, where pesticide application is necessary to mitigate crop loss.