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Significance Lacking any ability to store glucose, the mammalian brain relies on a constant glucose and oxygen supply via the cerebral vasculature. In the cortex, this supply is maintained by parallel arterioles and venules. Yet, mathematical modeling of both real and idealized cortical networks shows that, far from being perfused uniformly, the cortex is strewn with regions of very low flow. Increasing the number of perfusing vessels increases the number of low-flow spots. Minimizing the influence of low-flow spots sets an optimal arteriole–venule ratio that we find to be closely recapitulated in data from real mammalian cortices. Further, low-flow regions complicate the regulation of metabolite delivery with neuronal activity, leading to unintuitive changes in perfusion when penetrating vessels dilate.

BiVO4 possesses a suitable band gap for photoelectrochemical (PEC) water splitting to produce hydrogen, however, the performance of BiVO4 is limited by several adverse factors. The bulk charge recombination and...

Composite solid electrolytes (CSEs) containing polymer electrolytes and inorganic particulate fillers have the potential to attain excellent electrochemical performance and good interfacial contact with Li metal. Nevertheless, the performance of CSEs is still constrained by the low Li+ transference number (t Li+) and problems at the polymer–ceramic interface. In this study, we present a CSE with high t Li+ and promising comprehensive performance, in which the surface of LLZTO micron particles was grafted by lithium (4-styrenesulfonyl) (trifluoromethanesulfonyl) imide (LiSTFSI). The existence of LiSTFSI on the surface of modified particles was confirmed by FTIR spectroscopy and X-ray photoelectron spectroscopy measurements. These surface-modified particles were uniformly dispersed in the poly(vinylidenefluoride-hexafluoropropylene) (PVDF-HFP) matrix for the improved interfacial compatibility, by which CSEs (PFL@LCSE) were formed. Li@LLZTO particles were found by X-ray diffraction spectra to decrease the crystallinity of PFL@LCSE and to increase the ionic conductivity. Simultaneously, LiSTFSI on the surface of Li@LLZTO was able to restrict the migration of anions and improve the concentration polarization phenomenon inside the battery. PFL@LCSE exhibits high ionic conductivity (1.40 × 10–4 S·cm–1 at 30 °C), high t Li+ (0.59 at 60 °C), good mechanical strength, and remarkable ability to inhibit Li dendrite growth. Li/Li symmetrical and LFP/Li full batteries were assembled and demonstrated good cycling performance. It indicates that improving the interfacial compatibility between organic and inorganic electrolytes is a promising strategy for enhancing the performance of CSEs.

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