Exploring efficient and economical electrocatalysts and understanding the mechanism for alkaline hydrogen oxidation reaction (HOR) are crucial to facilitate the development of alkaline polymer electrolyte fuel cells (APEFCs). Herein, Ru 2 P was synthesized and used as an anodic HOR electrocatalyst for APEFC, achieving a peak power density of 1.3 W cm −2 , the highest value among Pt-free anode electrocatalysts reported under the same conditions. From the density functional theory (DFT) calculations and experimental results, it was found that besides the optimized hydrogen binding energy, the enhanced adsorption strength of oxygenated species (OH*) and the reduced work function of Ru 2 P contributed to the enhanced HOR performance. The normalized exchange current densities of Ru 2 P/C were 0.37 mA cm ECSA −2 and 0.27 mA μg Ru −1, respectively, both approximately three times higher than those of Ru when conducted in the rotating disk electrode (RDE) system. Our work provides a new pathway for exploring highly active Pt-free HOR electrocatalysts and expanding the family of anodic electrocatalysts for APEFCs.

Ir-based perovskite oxides show great promise for next-generation oxygen evolution reaction (OER) electrocatalysts in an acidic medium, but they are generally stuck with their uncontrollable surface amorphization and thus structural instability (e.g., serious Ir leaching) during OER. Herein, we report the high-yield chemical exfoliation of Ruddlesden–Popper layered perovskite Sr2IrO4 into protonated colloidal nanosheets with an undamaged perovskite framework. We further demonstrate the potential of protonated perovskite nanosheets to evade the trade-off between OER activity and structural stability. The 2D morphological benefit and nice monodispersity of these protonated perovskite nanosheets enable the facile fabrication of an ultralow-Ir-loading catalyst film (30 μg cm–2), which exhibits about 10 times higher activity than the IrO2 catalyst film and undergoes almost as much Ir leaching during OER. Our joint experimental and theoretical results also reveal that structural hydroxyl groups on the surface of protonated nanosheets participate in the catalytic cycle of OER, and the protonated layered perovskite framework represents an example of OER electrocatalyst that works with a non-traditional adsorbate evolution mechanism.

Herein, we constructed a DNA-mediated Au–Au dimer-based surface plasmon coupling electrochemiluminescence (SPC-ECL) sensor. In the SPC-ECL sensing system, graphite phase carbon nitride quantum dots (GCN QDs) worked as an ECL emitter. A DNA rigid chain structure was employed to connect two Au NPs in an equilateral triangle configuration to form the Au–Au dimers. Due to the hot spot effect, the designed Au–Au dimers had a strong electromagnetic field intensity, which can greatly enhance the ECL signal of GCN QDs than a single Au nanoparticle. The gap distance of dimers can be effectively regulated by the DNA length, which resulted in different electromagnetic field intensities. Therefore, the different SPC-ECL amplification effects on the GCN QD signal by Au–Au dimers have been revealed. The maximum ECL signal of GCN QDs can be enhanced fourfold based on the Au–Au dimers with a gap distance of 2 nm. Furthermore, the biosensor showed good analytical performance for the detection of breast cancer susceptibility gene 1 (BRCA1 genes) (1 fM–1 nM) with a detection limit of 0.83 fM. This work provided an effective and precise SPC-ECL sensing mode for the diagnosis and prognosis of breast cancer.

interaction, as well as being an environmentally friendly and readily abundant element. Among those wellknown miscellaneous interactions, iron (Fe) offers a degree of flexibility as it is capable of not only the ammonization from ammonia reaction [35,36] but also nitriding of steel, [37,38] as shown in Figure 1.