The development of bifunctional electrocatalysts for overall water splitting in acidic media is vital for polymer electrolyte membrane (PEM) electrolyzers, but still full of obstacles. Here, highly efficient acidic overall water splitting is realized by utilizing ultrasmall, monodispersed Iridium (Ir)-based nanoclusters (NCs) as the candidate, via a surfactant-free, wet-chemical, and large-scalable strategy. Benefiting from the high specific surface area, clean surface, and strong binding between NCs and supports, the IrM NCs exhibit attractive activities and durability for both oxygen evolution reaction and hydrogen evolution reaction in acidic electrolytes, with IrNi NCs showing the best performance. More significantly, in the overall water splitting, IrNi NCs reach 10 mA cm −2 at a cell voltage of only 1.58 V in 0.5 m H 2 SO 4 electrolyte, holding promises for potential implementation of PEM water electrolysis. This work opens a new avenue toward designing bifunctional “acidic stable” catalysts for efficient overall water splitting.
Cell-membrane-coated nanoparticles are widely studied due to their inherent cellular properties, such as immune escape and homologous homing. A cell membrane coating can also maintain the relative stability of nanoparticles during circulation in a complex blood environment through cell membrane encapsulation technology. In this study, we fused a murine-derived ID8 ovarian cancer cell membrane with a red blood cell (RBC) membrane to create a hybrid biomimetic coating (IRM), and hybrid IRM camouflaged indocyanine green (ICG)-loaded magnetic nanoparticles (Fe3O4-ICG@IRM) were fabricated for combination therapy of ovarian cancer. Fe3O4-ICG@IRM retained both ID8 and RBC cell membrane proteins and exhibited highly specific self-recognition of ID8 cells in vitro and in vivo as well as a prolonged circulation lifetime in blood. Interestingly, in the bilateral flank tumor model, the IRM-coated nanoparticles also activated specific immunity, which killed homologous ID8 tumor cells but had no effect on B16-F10 tumor cells. Furthermore, Fe3O4-ICG@IRM showed synergistic photothermal therapy, resulting in the release of whole-cell tumor antigens by photothermal-induced tumor necrosis, which further enhanced antitumor immunotherapy for primary tumor and metastatic tumor by activating CD8+ cytotoxic T cells and reducing regulatory Foxp3+ T cells. Together, the biomimetic Fe3O4-ICG@IRM nanoparticles showed synergistic photothermal-immunotherapy for ovarian cancer.
Polarity determines the oil resistance property of elastomers. In this work, three bio-based polyester elastomers (BPEs) with different mass fraction of ester groups ( E ) are designed and synthesized aiming to study the relationship of E and oil resistance performance, and to obtain bio-based elastomer materials with tunable oil resistance. Through adjusting the chain length of monomers, E of poly(ethylene glycol/1,3-propanediol/succinate/adipate/itaconate)(PEPSAI), poly(1,3-propanediol/1,4-butanediol/succinate/adipate/itaconate)(PPBSAI), and poly(1,3-propanediol/1,4-butanediol/sebacate/adipate/itaconate)(PPBSeAI) are ≈50.39%, 48.55%, and 39.68%, respectively. Results show that E has great influence on the oil resistance of BPEs. After being immersed in IRM-903 # oil for 72 h at room temperature, the changes in mass and volume of BPEs decrease along with the increasing mass fraction of ester groups, indicating improved oil resistance performance. PEPSAI with the highest mass fraction of ester groups presents better oil resistance and lower T g (better low-temperature resistance) than one of the most used commercial oil-resistant rubber nitrile rubber (N230S). Thus, this work provides a promising strategy to obtain bio-based oil resistant elastomers with practical value.