Enhancing Zn2+ Storage Performance by Constructing the Interfaces Between VO2 and Co-N-C Layers.

Vanadium oxides have aroused attention as cathode materials in aqueous zinc-ion batteries (AZIBs) due to their low cost and high safety. However, low ion diffusion and vanadium dissolution often lead to capacity decay and deteriorating stability during cycling. Herein, vanadium dioxides (VO2) nanobelts are coated with a single-atom cobalt dispersed N-doped carbon (Co-N-C) layer via a facile calcination strategy to form Co-N-C layer coated VO2 nanobelts (VO2@Co-N-C NBs) for cathodes in AZIBs. Various in-/ex situ characterizations demonstrate the interfaces between VO2 layers and Co-N-C layers can protect the VO2 NBs from collapsing, increase ion diffusion, and enhance the Zn2+ storage performance. Additional density functional theory (DFT) simulations demonstrate that Co─O─V bonds between VO2 and Co-N-C layers can enhance interfacial Zn2+ storage. Moreover, the VO2@Co-N-C NBs provided an ultrahigh capacity (418.7 mAh g-1 at 1 A g-1), outstanding long-term stability (over 8000 cycles at 20 A g-1), and superior rate performance.

Differential responses of soil bacteria, fungi and protists to root exudates and temperature.

The impact of climate warming on soil microbes has been well documented, with studies revealing its effects on diversity, community structure and network dynamics. However, the consistency of soil microbial community assembly, particularly in response to diverse plant root exudates under varying temperature conditions, remains an unresolved issue. To address this issue, we employed a growth chamber to integrate temperature and root exudates in a controlled experiment to examine the response of soil bacteria, fungi, and protists. Our findings revealed that temperature independently regulated microbial diversity, with distinct patterns observed among bacteria, fungi, and protists. Both root exudates and temperature significantly influenced microbial community composition, yet interpretations of these factors varied among prokaryotes and eukaryotes. In addition to phototrophic bacteria and protists, as well as protistan consumers, root exudates determined to varying degrees the enrichment of other microbial functional guilds at specific temperatures. The effects of temperature and root exudates on microbial co-occurrence patterns were interdependent; root exudates primarily simplified the network at low and high temperatures, while responses to temperature varied between single and mixed exudate treatments. Moreover, temperature altered the composition of keystone species within the microbial network, while root exudates led to a decrease in their number. These results emphasize the substantial impact of plant root exudates on soil microbial community responses to temperature, underscoring the necessity for future climate change research to incorporate additional environmental variables.

[Changes in the structure and function of soil prokaryotic communities in subalpine Picea asperata plantations]. / äºšé«˜å±±ç²—æžäº‘æ‰äººå·¥æž—åœŸå£¤åŽŸæ ¸å¾®ç”Ÿç‰©ç¾¤è½ç»“æž„ä¸ŽåŠŸèƒ½å˜åŒ–.

The structural and functional characteristics of soil prokaryotic community are important for maintaining ecosystem functions. In this study, we examined the diversity and compositions, the key drivers, as well as functional characteristics of prokaryotic communities in the rhizosphere and non-rhizosphere soils of Picea asperata with different stand ages using high-throughput sequencing technique and bioinformatics methods. The results showed that ß-diversity of soil prokaryotic communities in both rhizosphere and non-rhizosphere showed significant differences among different stand ages, but no significant difference between rhizosphere and non-rhizosphere in the same stand age. In terms of community composition at the phylum level, the relative abundances of Proteobacteria and Rokubacteria showed an increasing trend with the increases of stand age, while the relative abundance of Actinobacteria showed a decreasing trend, but no significant difference was observed between 75 year-old planted forests (PF75) and natural forests (NF). The relative abundances of Firmicutes and Thaumarchaeota in the soil of the 25 year-old planted forests (PF25) were significantly higher than in other planted forests and NF. At the genus level, the relative abundances of RB41, Terrimonas and Acidibacter showed an increasing trend with the increases of stand age, and RB41 and Terrimonas in rhizosphere soil of PF75 were significantly higher than those in NF. Soil properties and vegetation characteristics jointly influenced the structure of soil prokaryotic communities, with herb layer coverage, soil pH, total phosphorus, and total nitrogen as major drivers. The functional characteristics of soil prokaryotic communities were significantly different among different stand ages. The relative abundances of functions involved in carbon and nitrogen cycle, e.g., cellulolysis and nitrification, decreased with the increases of stand age, whereas that of sulfate respiration involved in the sulfur cycle increased. We proposed that the structure and functional characteristics of soil prokaryotic communities could serve as important indicators of the development stages of P. asperata forests. In the later stages of plantation forest development, soil nutrient availability could be improved by mediating phosphorus-dissolving and nitrogen-enhancing microorganisms to maintain the stability of the plantation ecosystem.