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With the unprecedentedly increasing demand for renewable and clean energy sources, the sodium‐ion battery (SIB) is emerging as an alternative or complementary energy storage candidate to the present commercial lithium‐ion battery due to the abundance and low cost of sodium resources. Layered transition metal oxides and Prussian blue analogs are reviewed in terms of their commercial potential as cathode materials for SIBs. The recent progress in research on their half cells and full cells for the ultimate application in SIBs are summarized. In addition, their electrochemical performance, suitability for scaling up, cost, and environmental concerns are compared in detail with a brief outlook on future prospects. It is anticipated that this review will inspire further development of layered transition metal oxides and Prussian blue analogs for SIBs, especially for their emerging commercialization.

Exosomes are a subset of extracellular vesicles that carry specific combinations of proteins, nucleic acids, metabolites, and lipids. Mounting evidence suggests that exosomes participate in intercellular communication and act as important molecular vehicles in the regulation of numerous physiological and pathological processes, including cancer development. Exosomes are released by various cell types under both normal and pathological conditions, and they can be found in multiple bodily fluids. Moreover, exosomes carrying a wide variety of important macromolecules provide a window into altered cellular or tissue states. Their presence in biological fluids renders them an attractive, minimally invasive approach for liquid biopsies with potential biomarkers for cancer diagnosis, prediction, and surveillance. Due to their biocompatibility and low immunogenicity and cytotoxicity, exosomes have potential clinical applications in the development of innovative therapeutic approaches. Here, we summarize recent advances in various technologies for exosome isolation for cancer research. We outline the functions of exosomes in regulating tumor metastasis, drug resistance, and immune modulation in the context of cancer development. Finally, we discuss prospects and challenges for the clinical development of exosome-based liquid biopsies and therapeutics.

Combining the advantages of homogeneous and heterogeneous catalysts,s ingle-atom catalysts (SACs) are bringing new opportunities to revolutionizeO RR catalysis in terms of cost, activity and durability.However,the lack of highperformance SACs as well as the fundamental understanding of their unique catalytic mechanisms call for serious advances in this field. Herein, for the first time,w ed evelop an Ir-N-C single-atom catalyst (Ir-SAC) whichm imics homogeneous iridium porphyrins for high-efficiency ORR catalysis.I na ccordance with theoretical predictions,the as-developed Ir-SAC exhibits orders of magnitude higher ORR activity than iridium nanoparticles with arecord-high turnover frequency (TOF) of 24.3 e À site À1 s À1 at 0.85 Vv s. RHE) and an impressive mass activity of 12.2 Amg À1 Ir ,which far outperforms the previously reported SACs and commercial Pt/C.A tomic structural characterizations and density functional theory calculations reveal that the high activity of Ir-SACi sa ttributed to the moderate adsorption energy of reaction intermediates on the mononuclear iridium ion coordinated with four nitrogen atom sites.

Despite 35 years of investigation, much remains to be understood regarding charge transport in semiconducting polymers, including the ultimate limits on their conductivity. Recently developed ion gel gating techniques provide a unique opportunity to study such issues at very high charge carrier density. Here we have probed the benchmark polymer semiconductor poly(3-hexylthiophene) at electrochemically induced three-dimensional hole densities approaching 10 21 cm À 3 (up to 0.2 holes per monomer). Analysis of the hopping conduction reveals a remarkable phenomenon where wavefunction delocalization and Coulomb gap collapse are disrupted by doping-induced disorder, suppressing the insulator-metal transition, even at these extreme charge densities. Nevertheless, at the highest dopings, we observe, for the first time in a polymer transistor, a clear Hall effect with the expected field, temperature and gate voltage dependencies. The data indicate that at such mobilities (B0.8 cm 2 V À 1 s À 1 ), despite the extensive disorder, these polymers lie close to a regime of truly diffusive band-like transport.

Ministry of Science and Technology of the People's Republic of China through the Twelfth Five-Year National Science and Technology Pillar Program.

A new class of oxygen reduction reaction (ORR) catalysts based on graphene quantum dots (GQDs) supported by graphene nanoribbons (GNRs) has been developed through a one-step simultaneous reduction reaction, leading to ultrahigh performance for O reduction with an excellent electrocatalytic activity (higher limiting current density and lower overpotential than those of platinum) and high selectivity and stability in alkaline media comparable to the best C-based ORR catalysts reported so far. Electron microscopy revealed numerous surface/edge defects on the GQD/GNR surfaces and at their interface to act as the active sites. This, coupled with efficient charge transfer between the intimately contacted GQDs and GNRs, rationalized the observed ultrahigh electrocatalytic performance for the resultant GQD-GNR hybrids. Thus, this study opens a new direction for developing low-cost, highly efficient, C-based ORR electrocatalysts.

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