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Climate change is increasing flooding in provinces of the south of the Yangtze River, posing challenges for promoting Styrax tonkinensis seedlings in these areas. To understand the physiological reasons for this species' intolerance to waterlogging, we observed biochemical parameters in one-year-old S. tonkinensis seedlings during two seasons. For 4 and 12 days in summer and winter experiments, respectively, we subjected seedlings to a pot-in-pot waterlogging treatment. Control groups were established at 0 h and 0 days. We examined indicators related to root vigor, reactive oxygen species (ROS), antioxidant enzymes, fermentative pathways, and more. The results displayed that decreased abscisic acid accumulation in roots inhibited water transport. Increased dehydrogenase and lactate dehydrogenase activity in roots promoted alcohol and lactate fermentation, causing toxic damage and reduced root vigor, impeding water absorption. In leaves, high ROS levels led to lipid peroxidation, exacerbating water loss from continuous transpiration. The high relative electric conductivity and low leaf relative water content indicated water loss, causing leaf wilting and shriveling. Conversely, winter seedlings, devoid of leaves, significantly reduced transpiration, and dormancy delayed root fermentation. With less ROS damage in roots, winter seedlings exhibited greater waterlogging tolerance. In summary, excessive water loss from leaves and inhibited vertical water transport contributed to low summer survival rates, while winter leafless dormancy and reduced ROS damage enhanced tolerance. Our findings provide insights for enhancing waterlogging resistance in S. tonkinensis amidst climate change challenges. • Reduced root vigor, decreased ABA content, active root fermentation hindered water absorption in roots. • ROS accumulation, lipid peroxidation, and transpiration led to leaf water loss. • Leaf water loss and water transport inhibition caused low S. tonkinensis survival. [ABSTRACT FROM AUTHOR]

Na-superionic conductor (NASICON) structured NaTi 2 (PO 4) 3 (NTP) as anode shows broad prospect in aqueous lithium ion battery. However, inherent low electrical conductivity of NaTi 2 (PO 4) 3 remains a pivotal issue to be resolved. Herein, we report N-doped carbon encapsulated NaTi 2 (PO 4) 3 microflower (NTP-CN) as anode for aqueous lithium ion battery, which is prepared via solvothermal way. NTP-CN with unique structural feature displays superb electrochemical performances. It delivers the discharge capacities of 131.2, 110.1, and 84.3 mAh g−1 at 0.2, 3.0, and 15 C, respectively, 38.8, 33.8, and 51.1 mAh g−1 higher than these of pristine NTP. NTP-CN also shows remarkable cycling stability at 6 C after 1000 cycles (capacity retention: 88.8%), superior to NTP (70.7%). The outstanding properties of NTP-CN may be due to that microflower structure can increase touching area between electrolyte and electrode, and carbon coating for electrode improves stability in aqueous electrolyte and ameliorates electrical conductivity. Moreover, nitrogen doping can further enhance hydrophilicity and conductivity of the sample, and also form lots of defects on electrode surface, which is beneficial for the intercalation/deintercalation of Li ions. This work reveals that the combination of microflower structure and N-doped carbon layer offers a promising method to improve electrochemical performances of NaTi 2 (PO 4) 3. [ABSTRACT FROM AUTHOR]

Chemically stable BaZr 0.8 Y 0.2 O 3-δ (BZY) is limited to applications because of its poor sintering behavior and low total electrical conductivity. The study aimed to enhance conductivity and sinterability for BaZr 0.8 Y 0.2 O 3-δ utilizing the partial replacement of Zr4+ with Hf4+. As expected, Hf4+ was doped into the lattice and BaZr 0.6 Hf 0.2 Y 0.2 O 3-δ (BZHY) was facilely sintered and reached a relative density above 94.79 (2)% at 1600 °C due to Hf4+ doping. The samples were quite dense with integral grains and there were no pores observed from the surface and cross-section. The samples displayed excellent chemical stability in H 2 , H 2 S, CO 2 and water steam containing atmosphere even in boiling water. Thermogravimetric analysis revealed that BZHY exhibited remarkably enhanced hydration ability over BZY. The electrical conductivities of the samples in different atmospheres were investigated from 300 to 700 °C. Compared with BZY, BZHY sample displayed a higher conductivity under the same conditions due to higher relative density, bigger grain size and better hydration ability. To test the electrolyte applicability, an impedancemetric type H 2 sensor consisting of ZnO sensing electrode and BZHY electrolyte was fabricated. The sensor showed excellent sensing performance and response signals varied logarithmically with the H 2 concentrations in the range of 200–600 ppm at 600 °C. [ABSTRACT FROM AUTHOR]

Perovskite proton conductors Ba x Zr 0.6 Hf 0.2 Y 0.2 O 3-δ (x = 0.9–1.03) were successfully prepared by high temperature solid state method. The influences of Ba-site non-stoichiometric on the phase composition, sinterability, chemical stability and conductivity of the samples were studied systematically. Ba excess can effectively enhance the sinterability of the samples, and promote the densification and grain growth of the samples. X-ray diffraction patterns display that all the samples have a single phase of cubic perovskite-type oxides. Ba 1.03 Zr 0.6 Hf 0.2 Y 0.2 O 3-δ is easily sintered and reaches a relative density above 98.51% at 1600 °C due to Ba-excessive. The grain size and electrical conductivity of the samples increases with the increase in Ba content from x = 0.9 to 1.03. The grain size of Ba 1.03 Zr 0.6 Hf 0.2 Y 0.2 O 3-δ sample is about 2 μm, and the total conductivity is 1.25 × 10−2 S cm−1 in 700 °C in wet air. All the samples display excellent chemical stability in H 2 , H 2 S, CO 2 , water vapor and boiling water, and the Ba-deficient sample was more excellent over Ba-excessive sample. • Excessive Ba can improve the sinterability of the samples and the grain size.. • The conductivity of Ba 1.03 Zr 0.6 Hf 0.2 Y 0.2 O 3-δ is 1.25 × 10−2 S cm−1 at 700 °C in wet air. • All the samples display excellent chemical stability under the test conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mo 2 CT x MXene protects Al current collector from corrosion in organic electrolyte. • An electrochemical strategy regulates F-functionalized Mo 2 CF x protective layer. • Mo 2 CF x elevates operating voltage of Al current collector over 5 V vs. Li/Li+. • Mo 2 CF x -Al has superior and uniform electroconductivity similar to bare Al. • NMC333||Li with Mo 2 CF x -Al cycles stably under a high cut-off voltage of 4.6 V. Elevating operation voltage of lithium ion battery (LIB) is inevitably restricted by the corrosion of cathode aluminum (Al) current collector. In this report, MXene (Mo 2 CT x) is proposed as an artificial passivation layer on Al surface. To broaden the electrochemical stability of Mo 2 CT x , a mild tactic of potentiostatic polarization is applied to tailor Mo 2 CT x terminal at around 5.3 V vs. Li/Li+ for 60 s. After electrochemical tailoring, the -F terminal ratio is significantly increased. The obtained Mo 2 CF x exhibits uniform electrical conductivity similar to bare Al and outstanding antioxidation over 5 V vs. Li/Li+. As a consequence, when Mo 2 CF x is requisitioned to protect Al current collector, a high-voltage LIB equipped with LiCo 1/3 Ni 1/3 Mn 1/3 O 2 (NMC333) in LiPF 6 electrolyte manifests an overall enhanced electrochemical performance under a high cut-off voltage of 4.6 V. The discharge capacity retention is increased from 7.0 % to 62.3 % after 500 cycles at 0.5C. And the rate performance at 3C is also improved by about 300 %. This work contributes to the surface engineering and application of MXene nanosheets, as well as provides an effective strategy for developing stable high-voltage LIBs. [ABSTRACT FROM AUTHOR]

• Metal boride was firstly proposed as a novel catalyst for VRFB. • TiB 2 nanoparticles has low cost, large surface area and good electrical conductivity. • TiB 2 displays excellent electrocatalytic performance toward V3+/V2+ couple. • TiB 2 modified cell exhibits superior VRFB energy storage performance. [Display omitted] Transition metal borides have broad application prospects in the field of electrochemistry due to their excellent physicochemical stability and electrical conductivity. In this study, metal boride (titanium boride, TiB 2) was first proposed as a novel catalyst for V3+/V2+ in vanadium redox flow battery. Nano-TiB 2 exhibits large specific surface area and great electrical conductivity, and shows excellent catalytic performance in V3+/V2+ redox reaction. The performance of TiB 2 as negative catalyst for cell was further investigated. Compared with pristine cell, TiB 2 modified cell displays much higher discharge capacity (16.9 mA h) after 50 cycles and the incipient energy efficiency increases by 6.5%. The cell with TiB 2 as the negative electrode catalyst exhibits excellent rate performance at 50–150 mA cm−2. Voltage efficiency and energy efficiency of modified cell are 8.7% and 7.5% higher than those of pristine cell at 150 mA cm−2, respectively. In conclusion, this work reveals that nano-TiB 2 is a promising catalyst for enhancing the electrochemical performance toward V3+/V2+ redox reaction for vanadium redox flow battery. [ABSTRACT FROM AUTHOR]

As a novel type of proton conductor, BaHfO 3 -based proton conductor has a promising application potential, but its poor sinterability and low conductivity limit its application as hydrogen separation membrane materials. In this paper, In and Sn co-doping BaHfO 3 strategy was adopted to further optimize its sinterability and electrical conductivity. BaHf 0.9−x In x Sn 0.1 O 3−δ (x = 0.05–0.25) proton conductors were prepared by high temperature solid state method. The results of X-ray diffraction show that In3+ and Sn4+ have been successfully doped into the lattice to form a cubic perovskite structure. BaHf 0.7 In 0.2 Sn 0.1 O 3−δ (BHSI) was facilely sintered and reached a relative density above 96.25% at 1600 °C. The scanning electron microscope observation shows that the introduction of In3+ and Sn4+ can effectively improve the sinterability and increase the grain size of the sample. High relative density and big grain size allow reducing the volume fraction of grain boundaries and increasing the electrical conductivity of BHSI. The total conductivity of BHSI in wet air reaches 5.69 × 10−3 S cm−1 at 700 °C. In addition, BHSI also shows excellent chemical stability in pure H 2 and CO 2 , 200 ppm H 2 S and water steam, and boiling water. The obtained BHSI membranes were evaluated for hydrogen separation under a mode-pure protonic conductor with external short circuit. The hydrogen separation performance of BHSI membrane was tested systematically. Gas humidification on the feed side and sweep side can obviously increase the hydrogen permeation fluxes. BHSI membrane still maintains a stable hydrogen permeation performance, even 3% CO 2 and 100 ppm H 2 S was introduced into the feed gas, respectively. • The sinterability of barium hafnate-based proton conductors is improved by In and Sn co-doping. • BaHf 0.7 In 0.2 Sn 0.1 O 3−δ exhibits the improved conductivity due to decreasing bulk and grain boundary resistances. • The BaHf 0.7 In 0.2 Sn 0.1 O 3−δ membrane shows high performance for hydrogen separation. [ABSTRACT FROM AUTHOR]