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Constructing a hierarchical 3D conductive network structure as the sulfur host is an effective attempt to mitigate the polysulfide (LiPS) shuttle and expedite the reaction kinetics in lithium–sulfur batteries (LSBs). In this research, 3D hollow Ti3C2 MXene spheres have been synthesized by the template method, with 1D carbon nanotubes (CNTs) grown in situ on their surface (Ti3C2@N-CNTs). The hollow Ti3C2 spheres avoid self-stacking thus exposing more active sites, while the 1D CNTs form an interconnected conductive network. The synergistic effect enhances the adsorption and catalytic conversion of LiPSs and simultaneously facilitates rapid ion diffusion and electron transfer. With these advantages, the LSBs constructed from Ti3C2@N-CNTs exhibit a satisfactory initial discharge capacity of 1214 mA h g−1 at 0.2C, as well as the average capacity decay rate per cycle is only 0.015% after 1000 cycles at 1C. Furthermore, an areal capacity of 4.3 mA h cm−2 can be achieved at a higher sulfur loading of 4.8 mg cm−2. [ABSTRACT FROM AUTHOR]

The Water Conservation Functional Zone and Ecological Environmental Supporting Zone (the Capital Two Zones in China), Zhangjiakou (ZJK) City, situated in China, has played a key role in mitigating water scarcity pressure on Beijing via delivering sustainable and high-quality water yield, as well as water conservation services aimed at maintaining the ecological functions of the Capital Two Zones. However, the changing mechanism for both water yield and water conservation services instigated by the combined impacts of human activities and climate change remains poorly understood. In this study, we used the Integrated Valuation of Ecosystem Services and Trade-offs Tools (InVEST) model to analyze the changes in water yield and water conservation services, revealing the impacts of different land use scenarios. The results showed significant forest and impervious land area increment, while the water surface area decreased sharply from 1990 to 2020, with obvious urbanization expansion in ZJK during the period. Average annual water yield and water conservation from 1990 to 2020 were recorded at 48.98 mm and 2.35 mm, respectively. Precipitation emerged as the primary driver of water yield and conservation service changes, while the south of ZJK generally exhibited higher water yield and conservation service than the north of ZJK. Results also indicate that grassland had the highest water yield, with an average of 56.60 mm, followed by forest (55.66 mm) and shrub (55.07 mm). Further, the forest had the highest water conservation value (3.73 mm), followed by shrub (2.56 mm), and grassland (2.37 mm), respectively. The return of cropland to forest scenario had the most substantial decrease in water yield. Findings suggest that precipitation has a direct impact on water yield and conservation services via the amount of atmospheric water input, while land use alteration contributes to changes in regional-scale water. [ABSTRACT FROM AUTHOR]