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The solid-electrolyte interphase (SEI) plays crucial roles for the reversible operation of lithium metal batteries. However, fundamental understanding of the mechanisms of SEI formation and evolution is still limited. Herein, we develop a depth-sensitive plasmon-enhanced Raman spectroscopy (DS-PERS) method to enable in-situ and nondestructive characterization of the nanostructure and chemistry of SEI, based on synergistic enhancements of localized surface plasmons from nanostructured Cu, shell-isolated Au nanoparticles and Li deposits at different depths. We monitor the sequential formation of SEI in both ether-based and carbonate-based dual-salt electrolytes on a Cu current collector and then on freshly deposited Li, with dramatic chemical reconstruction. The molecular-level insights from the DS-PERS study unravel the profound influences of Li in modifying SEI formation and in turn the roles of SEI in regulating the Li-ion desolvation and the subsequent Li deposition at SEI-coupled interfaces. Last, we develop a cycling protocol that promotes a favorable direct SEI formation route, which significantly enhances the performance of anode-free Li metal batteries. The solid-electrolyte interphase is crucial for most batteries, but its characterization is challenging. Here, authors develop a depth-sensitive plasmon-enhanced Raman spectroscopy method to enable in-situ and nondestructive resolving of its structure and chemistry as well as formation mechanisms. [ABSTRACT FROM AUTHOR]

Eggplant ( Solanum melongena L.) is one of the most popular vegetable in China. In July 2019, a serious stem canker disease of eggplant cv. Hangqieyiha has been found in commercial fields in Pingnan County, Fujian Province. The disease incidence ranged from 38% to 72%. The symptoms were found on stems but not on fruits. At first the lesions are small, more or less circular, later becoming elongated, blackish-brown lesions, eventually containing pycnidia. When stem girdling occurs, the shoot above the infected area wilts and dries up. The teleomorph of the fungus has not been encountered in sympotomatic stem. Single-conidial isolate has been obtained by using routine fungal-isolation methods and single-spore purification technique. The fungus was cultivated on potato dextrose agar (PDA), incubated under 12h/12h cycles of light and darkness until sporulation to determine. The fungus initially produced white fluffy aerial hyphae, forming relatively dense concentric pattern colony, which subsequently exhibited yellow-green pigmentation. Pycnidias had globose locules and prominent beaks, which immersed in medium, black, solitary, discoid or irregular. Conidiophores were colorless, separated, branched, 10.0 to 20.0 × 1.0 to 2.5 μm. Alpha-conidia were single-celled, ellipsoidal to fusiform, guttulate, 5.4 to 8.7 × 1.5 to 3.2 μm. Beta-conidia were found occasionally in older stock cultures, hyaline, filiform, hamate, and 17.0 to 26.9 × 0.86 to 1.23 μm. Based on these morphological characters, the fungus was identified as Phomopsis longicolla (Hobbs et al., 1985). The rDNA－ITS of the isolate FAFU01 was amplified with primers ITS1/ ITS4 (TCCGTAGGTGAACCTGCGG/ TCCTCCGCTTATTGATATGC) (White et al., 1990)，and A 578 bp sequence obtained (GenBank Accession No. MW380387 ) was 96% to 98.3% identical to the known sequence of P. longicolla or Diaporthe longicolla in GenBank. For further confirmation, P. longicolla specific primers Phom.I /Phom.II (GAGCTCGCCACTAGATTTCAGGG/GGCGGCCAACCAAACTCTTGT) (Zhang et al., 1997) were used and a 337-bp amplification product was obtained which was previously reported only for  P. longicolla , whereas no product was amplified from control. Based on these morphological and molecular characters, the fungus was identified as P. longicolla . In greenhouse tests, each of 35-day-old plants of eggplant cv. Hangqieyihao was maintained in 30-cm-diameter pot. Healthy stem on the plants was wounded by pinpricking. Both wounded and non-wounded stems were inoculated respectively with mycelial plugs (4 mm in diameter) from a 7-day-old PDA culture or PDA medium plugs as controls, with six replicates. The plants were covered with plastic bags to maintain high relative humidity for two days. Four days after inoculation, the plugs were washed from the stems. Thirty-five days after inoculation, canker lesions and small, black pycnidias, which were similar to those in the field, were observed on the surface of non-wounded and wounded healthy stems inoculated with pathogen, whereas all the control stems remained healthy. The fungi was re-isolated from the infected stems of plants and was further confirmed with the species-specific primers. These results confirmed the fungus's pathogenicity. This is the first report of P. longicolla causing stem canker in eggplant in Fujian Province, China.