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The electrochemical CO 2 reduction over Cu catalysts has shown great potential in producing a wide range of valuable chemicals, but it is still plagued by a poor controllability on product distribution. Herein, we demonstrate an effective regulation of CO 2 reduction paths through a preanodization treatment of Cu foil electrodes in different electrolytes. The Cu electrode exhibits a superior C 1 and C 2+ product selectivity after being preanodized in NaClO 4 (Cu- NaClO 4 ) and Na 2 HPO 4 electrolyte (Cu- Na 2 HPO 4 ), respectively. Combined with in situ electrochemical Raman, ATR-SEIRAS, and SEM characterizations, the preferential C 1 path is due to the deposition of many Cu nanocrystals with dominant Cu(111) facets on the Cu- NaClO 4 electrode. In contrast, the preferential C 2+ path over the Cu- Na 2 HPO 4 is attributed to formation of a unique Cu nanodendritic morphology, which strengthens the *CO intermediate adsorption and induces an environment of low local H 2 O/CO 2 stoichiometric ratio, thus facilitating C-C coupling for C 2+ production. Our findings may shed light on the rational control of the CO 2 reduction path through engineering of the Cu surface structure.

Nanotechnology-based RNA interference (RNAi) has shown great promise in overcoming the limitations of traditional clinical treatments for glioblastoma (GBM). However, because of the complexity of brain physiology, simple blood-brain barrier (BBB) penetration or tumor-targeting strategies cannot entirely meet the demanding requirements of different therapeutic delivery stages. Herein, we developed a charge conversional biomimetic nanoplatform with a three-layer core-shell structure to programmatically overcome persistent obstacles in siRNA delivery to GBM. The resulting nanocomplex presents good biocompatibility, prolonged blood circulation, high BBB transcytosis, effective tumor accumulation, and specific uptake by tumor cells in the brain. Moreover, red blood cell membrane (RBCm) disruption and effective siRNA release can be further triggered elegantly by charge conversion from negative to positive in the endo/lysosome (pH 5.0-6.5) of tumor cells, leading to highly potent target-gene silencing with a strong anti-GBM effect. Our study provides an intelligent biomimetic nanoplatform tailored for systemically siRNA delivery to GBM, leveraging Angiopep-2 peptide-modified, immune-free RBCm and charge conversional components. Improved therapeutic efficacy, higher survival rates, and minimized systemic side effects were achieved in orthotopic U87MG-luc human glioblastoma tumor-bearing nude mice.

This report focuses on a novel strategy for the preparation of transition metal-MoS 2 hybrid nanoclusters based on a one-step, dual-target magnetron sputtering, and gas condensation process demonstrated for Ni-MoS 2 . Aberration-corrected STEM images coupled with EDX analysis confirms the presence of Ni and MoS 2 in the hybrid nanoclusters (average diameter = 5.0 nm, Mo:S ratio = 1:1.8 ± 0.1). The Ni-MoS 2 nanoclusters display a 100 mV shift in the hydrogen evolution reaction (HER) onset potential and an almost 3-fold increase in exchange current density compared with the undoped MoS 2 nanoclusters, the latter effect in agreement with reported DFT calculations. This activity is only reached after air exposure of the Ni-MoS 2 hybrid nanoclusters, suggested by XPS measurements to originate from a Ni dopant atoms oxidation state conversion from metallic to 2+ characteristic of the NiO species active to the HER. Anodic stripping voltammetry (ASV) experiments on the Ni-MoS 2 hybrid nanoclusters confirm the presence of Ni-doped edge sites and reveal distinctive electrochemical features associated with both doped Mo-edge and doped S-edge sites which correlate with both their thermodynamic stability and relative abundance.