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The remarkable uplift of the Tibetan Plateau in the Neogene had great impacts on the climate and environment of East Asia and even the world. Therefore, establishment of the Neogene stratigraphic framework of the Tibetan Plateau is of great significance to research in various fields of geosciences. Based on marine sediments, the international chronostratigraphic system of the Neogene is divided into six stages in the Miocene and two stages in the Pliocene. Since the beginning of the Cenozoic, the share of terrestrial strata on continents has increased rapidly. By the Neogene, it had far exceeded that of marine strata, and almost all deposits on the Tibetan Plateau and its surrounding areas were terrestrial strata. In China, the Miocene includes five stages and the Pliocene includes two stages. Except for the Tunggurian of the Miocene, which has a lower boundary at 15 Ma, the other stages have the same paleomagnetic definitions and time intervals as the corresponding international marine stages. Mammalian fossils play a very important role in the division and correlation of Cenozoic terrestrial strata, and rodent, carnivore, proboscidean, perissodactyl and artiodactyl fossils are especially important in Neogene terrestrial biostratigraphy. There are many basins with well-exposed strata and abundant mammalian fossils in the Tibetan Plateau. The lower boundary stratotype sections of the Neogene Xiejian and Bahean stages are located respectively in the Xining and Linxia basins, and there are precise paleomagnetic dates in coordination with mammalian fossils. The lower boundary stratotypes of other stages can also be effectively determined in the Tibetan Plateau. Many first appearing mammalian genera in East Asia also appeared in the Tibetan Plateau and its surrounding areas, especially in the Linxia Basin on the northeast margin and in the Siwaliks on the southwest margin. Among them, Prodeinotherium first appeared at the bottom of the Miocene in the Siwaliks, and the earliest Hipparion of the Old World first appeared at the bottom of the Bahean Stage in the Linxia Basin. Carbon and oxygen isotope analysis of enamel and paleosols of Cenozoic sediments and mammal fossils in the Tibetan Plateau and its surrounding areas have been used to reconstruct the climate, environment and vegetation development characteristics, and revealed that these changes were not only related to global change, but also had regional features. Evidence of the Late Miocene C4 plant expansion event based on carbon isotope changes comes from the southern margin of the Tibetan Plateau, but in sharp contrast, δ13C indicates that there was still no clear or significant C4 plant signal on the northern margin of the Tibetan Plateau until the end of the Neogene. The δ18O analysis shows that there were several major climate change events in the Cenozoic, especially in the Late Miocene at about 7 Ma, when positive drift of δ18O indicates that the northern and southern sides of the Tibetan Plateau were changing to drier environments. The strong uplift of the Tibetan Plateau in the Late Miocene strengthened the thermal contrast between sea and land, which strengthened monsoon circulation and led to the expansion of C4 vegetation in South Asia. However, the East Asian summer monsoon, which can bring atmospheric precipitation and a climate suitable for C4 plants to northern China, was not enough to affect the northern Tibetan Plateau. The Tibetan Plateau on the whole rose to an altitude of about 3000 m in the Miocene, becoming a barrier to mammalian migration; it reached its modern altitude of more than 4000 m in the Pliocene, thus forming a cryosphere environment, which led to the emergence of ancestral types of the Ice Age fauna. [ABSTRACT FROM AUTHOR]

[Display omitted] • A low-cost, green, selective electrolysis process for Li recovery from spent LiFePO 4. • High performance LiFePO 4 was synthesised by impurity removal regeneration process. • The electrolysis and regeneration process makes full use of spent LiFePO 4. In this paper, a green, efficient and low-cost process for the selective recovery of lithium from spent LiFePO 4 by anodic electrolysis is proposed. The leaching rates of Li, Fe and P under different conditions were explored and the optimal conditions are obtained. In the optimal conditions, Li, Fe and P leaching rates were 96.31%, 0.06% and 0.62% respectively. The Li/Fe selectivity was over 99.9%. The product obtained is isostructural FePO 4 and retains the original particle morphology. The FePO 4 obtained can be synthesised into LiFePO 4 /C by direct regeneration process or impurity removal regeneration process. The material synthesized by the latter process has a better electrochemical performance, with a discharge specific capacity of 144.5 mAh/g at 1.0C and a capacity retention of 92.0% over 500cycles. The superior performance can be attributed to an impurity removal process that reduced agglomeration and improved particle morphology. [ABSTRACT FROM AUTHOR]

Metal fluorides (MFs) are regarded as high‐capacity conversion cathode materials for next‐generation lithium‐ion batteries with high energy density. However, these cathodes suffer from poor electronic conductivity, sluggish reaction kinetics, and deleterious cathode solid electrolyte interface (CEI) formation, which may cause rapid cell degradation upon cycling. Herein, a low temperature chemical vapor deposition (CVD) carbon coating technology is successfully achieved to coat MFs‐FeF2 with a thin amorphous carbon layer, which promotes the formation of a stable CEI with improved electronic and ionic transport property. Consequently, a discharge capacity higher than 450 mAh g−1 of the CVD coated FeF2 is achieved with a capacity retention at about 75% after 2500 cycles in a saturated electrolyte. Moreover, an unprecedented cycling performance with the discharge capacity of 350 mAh g−1 after 500 cycles in a super diluted electrolyte is also achieved. Advanced cryo‐electron microscopy reveals that the carbon coating significantly suppresses the undesirable CEI formation and promotes the formation of a thin CEI with excellent chemo‐mechanical property. This work provides a feasible technology to stabilize the important interface on MFs and offers a new strategy to accelerate the commercial adoption of such cathodes. [ABSTRACT FROM AUTHOR]

The shuttle of polysulfides and slow sulfur redox kinetics are the two main issues in the practical application of lithium sulfur (Li-S) batteries. The interface-induced electric fields produced in MnO 2 -based conductive composites are proposed to solve the above obstacles. Herein, a novel hybrid structure of birnessite-MnO 2 nanosheets in situ formed inside polyaniline nanotubes (NSs-MnO 2 @PANI) is prepared and applied as a catalytic host in Li-S batteries. The DFT calculation combined with experiments reveal the interface-induced electric field with a direction pointing from PANI to birnessite-MnO 2 is created, which would induce interface charge redistribution and result in electron-rich MnO 2 region and electron-deficient PANI region, optimizing the strong anchoring of polysulfides and their fast catalytic conversions. Owing to the interfacial synergy, the NSs-MnO 2 @PANI/S cathode delivers higher capacity than PANI/S at rates from 0.1 C (1473.7 vs. 467.5 mAh g−1) to 5 C (513.2 vs. 38.1 mAh g−1), with a low decay rate of 0.054% during 500 cycles at 0.2 C. Further, at an extremely high sulfur loading of 15.9 mg cm−2, the areal capacity achieves a high level of 10.2 mAh cm−2 at 0.05 C, with stable cycling at 1 C. Our work provides new insights for attaining high-energy and stable Li-S batteries. To overcome the low conductivity, the shuttling and sluggish redox kinetics of polysulfides for lithium-sulfur batteries, a novel hybrid structure of birnessite-MnO 2 nanosheets in situ formed inside polyaniline nanotubes (NSs-MnO 2 @PANI) was designed and applied as a catalytic host. The interface-induced electric field with a direction pointing from PANI to birnessite-MnO 2 was created at the two-phase interface of MnO 2 @PANI, which could optimize the strong anchoring of polysulfides and their fast catalytic conversions. [Display omitted] • An ingenious nanoengineering design for a newly sulfur host was reported. • Birnessite-MnO 2 nanosheets were in situ formed inside PANI nanotubes. • The interface-induced electric field was created pointing from PANI to MnO 2. • The NSs-MnO 2 @PANI hybrid combined strong anchoring and catalytic function. • Li-S batteries with superior electrochemical performances were obtained. [ABSTRACT FROM AUTHOR]

• High Lithium Extraction Rate. • Success direct regeneration of de-lithiated product. • Mechanism about de-lithiation and regeneration processes. The recycling of spent lithium-ion batteries has become an urgent imperative. Electrochemical technology is emerging as an environmentally friendly approach for selectively extracting lithium from discarded cathode materials, garnering significant attention. However, the lack of a clear understanding of the structural evolution during the de-lithiation process, and the re-lithiation mechanism of transition-metal oxides after lithium extraction, hinder the direct regeneration of de-lithiated materials into battery-worthy materials. This limitation also impeds the further advancement of this promising technology. Here, for the first time the structural transformation associated with water-molecule intercalation during the electrochemical process of spent layer material (LiNi 0.55 Co 0.15 Mn 0.3 O 2) is demonstrated. X-ray diffraction technique monitors the structural evolution upon de-lithiation, revealing an unusual phase transformation from H3 to "H4" driven by water-molecule intercalation. This transformation triggers significant lattice expansion along c -axis and introduces notable lattice distortion in de-lithiated material. These characteristics render direct calcination for material regeneration impractical, due to lattice collapse from dehydration, obstructing lithium intercalation at high temperatures. Interestingly, low-temperature calcination can endow resynthesized materials with a well-ordered layer structure after creating a lithium-water-balance layer structure for de-lithiated materials by hydrothermal process. Consequently, the regenerated material delivers a capacity of 132.5 mAh/g at 5C. [ABSTRACT FROM AUTHOR]