Safe and long cycle life electrode materials for lithium-ion batteries are significantly important to meet the increasing demands of rechargeable batteries. Niobium pentoxide (Nb O ) is one of the highly promising candidates for stable electrodes due to its safety and minimal volume expansion. Nevertheless, pulverization and low conductivity of Nb O have remained as inherent challenges for its practical use as viable electrodes. A highly facile method is proposed to improve the overall cycle retention of Nb O microparticles by ammonia (NH ) gas-driven nitridation. After nitridation, an ultrathin surficial layer (2 nm) is formed on the Nb O , acting as a bifunctional nanolayer that allows facile lithium (Li)-ion transport (10-100 times higher Li diffusivity compared with pristine Nb O microparticles) and further prevents the pulverization of Nb O . With the subsequent decoration of silver (Ag) nanoparticles (NPs), the low electric conductivity of nitridated Nb O is also significantly improved. Cycle retention is greatly improved for nitridated Nb O (96.7%) compared with Nb O (64.7%) for 500 cycles. Ag-decorated, nitridated Nb O microparticles and nitridated Nb O microparticles exhibit ultrastable cycling for 3000 cycles at high current density (3000 mA g ), which highlights the importance of the surficial nanolayer in improving overall electrochemical performances, in addition to conductive NPs.

Ag nanoparticle-decorated ZnCo2O4 hollow spheres are synthesized by using MOF templates and an Ag-mirror reaction, for high-performance lithium-ion battery anode materials.

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The secretion of Bacillus stearothermophilus L1 lipase in Saccharomyces cerevisiae was investigated by employing a fusion partner, a cellulose-binding domain (CBD) from Trichoderma harzianum endoglucanase II (THEG). The CBD was connected to the N-terminal of L1 lipase through an endogenous linker peptide from THEG. The expression cassette for the fusion protein in S. cerevisiae was constructed using the alpha-amylase signal peptide and the galactose-inducible GAL10 promoter. Secretion of CBD-linker-L1 lipase by this fusion construct was dramatically 7-fold enhanced, compared with that of the mature L1 lipase without CBD-fusion. The fusion protein was secreted into the culture medium, reaching levels of approximately 1.3 g/l in high-cell-density fed-batch cultures. Insertion of a KEX2 cleavage site into the junction between CBD-linker and L1 lipase resulted in the same level of enhanced secretion, indicating that the CBD-linker fusion probably plays a critical role in secretion from endoplasmic reticulum to Golgi apparatus. Therefore, the CBD from THEG can be used both as an affinity tag and as a secretion enhancer for the secretory production of heterologous proteins in S. cerevisiae, since in vivo breakage at the linker was almost negligible.

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