Rechargeable Li-S batteries(LSBs)are emerging as an important alternative to lithium-ion batteries(LIBs),owing to their high energy densities and low cost;yet sluggish redox kinetics of LiPSs results in inferior cycle life.Herein,we prepared multifunctional self-supporting hyphae carbon nanobelt(HCNB)as hosts by carbonization of hyphae balls of Rhizopus,which could increase the S loading of the cathode without sacrificing reaction kinetics.Trace platinum(Pt)nanoparticles were introduced into HCNBs(PtHCNBs)by ion-beam sputtering deposition.Based on the X-ray photoelectron spectroscopy analyses,the introduced trace Pt regulated the local electronic states of heteroatoms in HCNBs.Electrochemical kinetics investigation combined with operando Raman measurements revealed the accelerated reaction mechanics of sulfur species.Benefiting from the synergistic catalytic effect and the unique structures,the as-prepared PtHCNB/MWNCT/S cathodes delivered a stable capacity retention of 77%for 400 cycles at 0.5 C with a sulfur loading of 4.6 mg cm^(-2).More importantly,remarkable cycling performance was achieved with an high areal S loading of 7.6 mg cm^(-2).This finding offers a new strategy to prolong the cycle life of LSBs.
Ingenious design and fabrication of advanced carbon-based sulfur cathodes are extremely important to the development of high-energy lithium-sulfur batteries,which hold promise as the next-generation power source.Herein,for the first time,we report a novel versatile hyphae-mediated biological assembly technology to achieve scale production of hyphae carbon fibers(HCFs)derivatives,in which different components including carbon,metal compounds,and semiconductors can be homogeneously assembled with HCFs to form composite networks.The mechanism of biological adsorption assembly is also proposed.As a representative,reduced graphene oxides(rGOs)decorated with hollow carbon spheres(HCSs)successfully co-assemble with HCFs to form HCSs@rGOs/HCFs hosts for sulfur cathodes.In this unique architecture,not only large accommodation space for sulfur but also restrained volume expansion and fast charge transport paths are realized.Meanwhile,multiscale physical barriers plus chemisorption sites are simultaneously established to anchor soluble lithium polysulfides.Accordingly,the designed HCSs@rGOs/HCFs-S cathodes deliver a high capacity(1189 mA h g^(-1)at 0.1 C)and good high-rate capability(686 mA h g^(-1)at 5 C).Our work provides a new approach for the preparation of high-performance carbon-based electrodes for energy storage devices.
Bacterial-fungal interactions are widespread in nature.We observed that pear orchards affected by Cytospora pyri(formerly Valsa pyri)were often accompanied with Erwinia amylovora.However,the relationship of the two pathogens was unclear.The objective of this study was to determine whether the synergistic effect exists between E.amylovora and C.pyri.We first analyzed the coexistence frequencies of E.amylovora and C.pyri in pear trees.Virulence of the two pathogens,growth,physical interactions,amylovoran production,and expression of genes for amylovoran biosynthesis were conducted.Our results showed that E.amylovora and C.pyri could coexist on the same lesion and caused much more severe disease.We also found that E.amylovora could physically attach to C.pyri and the expression of amylovoran biosynthesis genes were up-regulated with fungal metabolite treatment.These results indicate that E.amylovora and C.pyri can cooperatively interact,which provides C.pyri with an opportunity to promote bacterial dispersal and production of virulence factor in E.amylovora.
Bioaerosols exhibit significant broadband extinction performance and have vital impacts on climate change,optical detection,communication,disease transmission,and the development of optical attenuation materials.Microbial spores and microbial hyphae represent two primary forms of bioaerosol particles.However,a comprehensive investigation and comparison of their optical properties have not been conducted yet.In this paper,the spectra of spores and hyphae were tested,and the absorption peaks,component contents,and protein structural differences were compared.Accurate structural models were established,and the optical attenuation parameters were calculated.Aerosol chamber experiments were conducted to verify the optical attenuation performance of microbial spores and hyphae in the mid-infrared and far-infrared spectral bands.Results demonstrate that selecting spores and hyphae can significantly reduce the average transmittance from 21.2%to 6.4%in the mid-infrared band and from 31.3%to 19.6%in the far-infrared band within three minutes.The conclusions have significant implications for the selection of high-performance microbial optical attenuation materials as well as for the rapid detection of bioaerosol types in research on climate change and the spread of pathogenic aerosols.