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Abstract Disentangling the limitations of O-O bond activation and OH* site-blocking effects on Pt sites is key to improving the intrinsic activity and stability of low-Pt catalysts for the oxygen reduction reaction (ORR). Herein, we integrate of PtFe alloy nanocrystals on a single-atom Fe-N-C substrate (PtFe@FeSAs-N-C) and further construct a ferromagnetic platform to investigate the regulation behavior of the spin occupancy state of the Pt d-orbital in the ORR. PtFe@FeSAs-N-C delivers a mass activity of 0.75 A mgPt −1 at 0.9 V and a peak power density of 1240 mW cm−2 in the fuel-cell, outperforming the commercial Pt/C catalyst, and a mass activity retention of 97%, with no noticeable current drop at 0.6 V for more than 220 h, is attained. Operando spectroelectrochemistry decodes the orbital interaction mechanism between the active center and reaction intermediates. The Pt dz 2 orbital occupation state is regulated to t 2g 6 e g 3 by spin-charge injection, suppressing the OH* site-blocking effect and effectively inhibiting H2O2 production. This work provides valuable insights into designing high-performance and low-Pt catalysts via spintronics-level engineering.

Abstract Although the closed pore structure plays a key role in contributing low-voltage plateau capacity of hard carbon anode for sodium-ion batteries, the formation mechanism of closed pores is still under debate. Here, we employ waste wood-derived hard carbon as a template to systematically establish the formation mechanisms of closed pores and their effect on sodium storage performance. We find that the high crystallinity cellulose in nature wood decomposes to long-range carbon layers as the wall of closed pore, and the amorphous component can hinder the graphitization of carbon layer and induce the crispation of long-range carbon layers. The optimized sample demonstrates a high reversible capacity of 430 mAh g−1 at 20 mA g−1 (plateau capacity of 293 mAh g−1 for the second cycle), as well as good rate and stable cycling performances (85.4% after 400 cycles at 500 mA g−1). Deep insights into the closed pore formation will greatly forward the rational design of hard carbon anode with high capacity.

Highlights The intimate NG@SiC heterostructure has been constructed via a direct thermal decomposition method. The NG@SiC heterostructure anode delivers enhanced capacity and cycling stability both in the half-cell and in the full cell. DFT analysis reveals that this NG@SiC anode possesses lower lithium-ion adsorption energy and higher charge and discharge rates.

In-vehicle crowding is an external cost imposed on passengers by public transport. It is necessary to quantify the crowding discomfort to measure its influence on passengers’ travel choice. This study presents a stated preference survey embedded with revealed preference to investigate the influence of in-vehicle crowding on the travel choice behavior. The in-vehicle crowding degree is measured as standing density. Considering the in-vehicle environment and the subjective perception of passengers, the classification criteria for the in-vehicle crowding degree of bus transit are put forward. Then, the mixed logit model is used to establish the utility function of bus passenger travel choice behavior under different in-vehicle crowding degrees, and the value of travel time is calculated. Also, the functional relationship between in-vehicle crowding and travel time value is identified. In addition, by converting in-vehicle crowding into time, the travel impedance model considering in-vehicle crowding and the crowding value of time multipliers are defined. A study of Shanghai bus transit shows that when the standing density is higher than 7.5 passengers per square meter, bus passengers are willing to exchange 12.83 Chinese Yuan RMB for 1-hour travel time saving, and the perceived in-vehicle time is twice as long as the actual in-vehicle time. This study provides a reference for improving the attraction of bus transit and easing the decline in bus rides.

Increasingly diverse pathogen occurrence in coastal and mariculture areas demands improved monitoring platforms to prevent economic and public health implications. Accessible databases with up-to-date knowledge and taxonomy are critical for detecting and screening environmental pathogens. Condensed from over 3000 relevant reports in peer reviewed articles, we constructed an aquaculture bacterial pathogen database that provides specialized curation of over 210 bacterial pathogenic species impacting aquaculture. Application of the aquaculture bacterial pathogen database to environmental DNA metabarcoding monitoring data in Hong Kong coastal and mariculture waters effectively characterized regional pathogen profiles over a one-year period and improved identification of new potential pathogen targets. The results highlighted the increase in potential pathogen abundance related to aquaculture activity and the associated inorganic nitrogen load, which was chiefly due to the enrichment of Vibrio during the atypical dry winter season. The value of the aquaculture bacterial pathogen database for empowering environmental DNA-based approaches in coastal marine pathogen surveillance benefits water resource management and aquaculture development on a global scale.

Abstract Aqueous redox flow batteries, by using redox‐active molecules dissolved in nonflammable water solutions as electrolytes, are a promising technology for grid‐scale energy storage. Organic redox‐active materials offer a new opportunity for the construction of advanced flow batteries due to their advantages of potentially low cost, extensive structural diversity, tunable electrochemical properties, and high natural abundance. In this review, we present the emergence and development of organic redox‐active materials for aqueous organic redox flow batteries (AORFBs), in particular, molecular engineering concepts and strategies of organic redox‐active molecules. The typical design strategies based on organic redox species for high‐capacity, high‐stability, and high‐voltage AORFBs are outlined and discussed. Molecular engineering of organic redox‐active molecules for high aqueous solubility, high chemical/electrochemical stability, and multiple electron numbers as well as satisfactory redox potential gap between the redox pair is essential to realizing high‐performance AORFBs. Beyond molecular engineering, the redox‐targeting strategy is an effective way to obtain high‐capacity AORFBs. We further discuss and analyze the redox reaction mechanisms of organic redox species based on a series of electrochemical and spectroscopic approaches, and succinctly summarize the capacity degradation mechanisms of AORFBs. Furthermore, the current challenges, opportunities, and future directions of organic redox‐active materials for AORFBs are presented in detail.

Abstract Despite of superior performance of the oxide‐derived copper (OD‐Cu) in producing valuable hydrocarbons during CO2RR, its fabrication process is still ambiguous and complicated. In this work, we develop a simple microwave‐assisted method to synthesize the oxide‐derived Cu nanosheet (OD‐Cu NS) and reveal that the oxidation state of Cu species is controlled by varying the Cu precursor amount. Notably, the simultaneous formation of nano‐sized Cu domains influence the surface roughness of OD‐Cu NS. The partially oxidized Cu surface exhibits a superior faradaic efficiency (FE) of C2+ products up to 72%, along with a partial current density of 55 mA cm−2 in a neutral KHCO3 solution. More importantly, the as‐obtained OD‐Cu NS shows a synergetic effect on dissociating of CO2 molecules by the strong binding energy and promoting of C2+ compounds productivity by the enlarged electrochemical surface area. This work provides a new insight for designing efficient OD‐Cu catalysts toward CO2RR.

Abstract The electrochemical reduction reaction of carbon dioxide (CO2RR) is considered to be an effective way to realize carbon neutrality. As a type of intensively studied materials, covalent organic frameworks (COFs) with a tunable pore structure and various functional groups are promising catalysts for CO2RR. Herein, COF synthesized by 2,6‐diaminoanthraquinone and 2,4,6‐triformylphloroglucinol is employed to assist the synthesis of electrocatalysts from Cu single atoms (SAs) to nanoclusters by controlling the electrodeposition. A tandem catalyst for CO2‐to‐CH4 conversion is thus achieved by the Cu nanoclusters dispersed among the isolated Cu SAs in the COF network. It is proposed that CO2 is first reduced to CO over the atomically isolated Cu SAs, followed by diffusion onto the neighboring Cu nanoclusters for further reduction into CH4. In addition, mechanistic analysis suggests that the coordinated K+ ions on the COF network promote the activation of CO2 and the adsorption of reaction intermediates, thus realizing the suppressed hydrogen evolution reaction and selective production of CH4. This study presents a new insight of COFs for the confined synthesis of a tunable SA to nanocluster electrocatalysts, disclosing the great potential of COFs in electrocatalysis.

The ligand-tailored SnO2 QDs ETL with multi-functional terminal groups in situ refines the buried interfaces with both the perovskite and transparent electrode via enhanced interface binding and perovskite passivation.

Abstract Spinel oxides are considered as promising low‐cost non‐precious metal electrocatalysts for oxygen evolution reaction (OER) due to their desirable catalytic activities and fast kinetics. However, as a result of the structural complexity of spinel oxides, systematic and in‐depth studies on enhancing the OER performance of spinel oxides remain inadequate. In particular, the construction of active sites regarding the large number of unoccupied octahedral interstices has not yet been explored. Herein, more octahedral sites with high OER activities are constructed on the surface of spinel oxides via a cationic misalignment, which is induced by the defects in the spinel oxide solutions, i.e., MoFe2O4 and CoFe2O4 nanosheets supported on an iron foam (MCFO NS/IF). With increased active sites and modified electronic structure, the state‐of‐the‐art electrocatalyst exhibits the excellent OER catalytic activity with an onset potential of 1.41 V versus RHE and an overpotential of 290 mV to achieve a current density of 500 mA cm−2. Moreover, such an electrocatalyst also demonstrates fast kinetics with the Tafel slope of 38 mV dec−1 and superior durability by maintaining the OER activity at 250 mA cm−2 for 1000 h.

Abstract Herein, we constructed urchin‐like TiO2 hollow nanospheres (HNSs) by hydrothermal targeted etching, and used it as a substrate to load semi‐metal 1T′‐MoS2 nanosheets as effective nitrogen reduction reaction (NRR) electrocatalysts. 1T′‐MoS2/TiO2 HNSs composites display outstanding NRR activity with the highest NH3 yield of 29.62 μg h−1 mg−1cat. at −0.75 V versus RHE. Besides, the highest FE of 24.9% is obtained at −0.65 V. The remarkable NRR performance is attributed to the high conductivity of 1T′‐MoS2 and the urchin‐like structure of TiO2 hollow nanospheres. DFT calculations display that the 1T′‐MoS2 in 1T′‐MoS2/TiO2 makes the activation and further reduction of *N2 more thermodynamically favorable than pristine TiO2, contributing to better NRR catalytic activities. 15N isotopic labeling experiment reveals that N in produced NH3 comes from N2 of electrolyte.

Background and objective The aim of this study is to establish a HRM (high resolution melting curve) method for detection of deletion in human BIM gene and to detect this site deletion with the above method in 30 lung cancer samples and 30 normal samples. Methods The primers for detection of BIM deletion were designed and synthesized. The HRM method for geng deletion was established. And select the part of samples to detect BIM delection by normal PCR and sequencing assay. The Tm value of wild type PCR products was higher than that of the deletion PCR products. The difference of the corresponding Tm value is 2.5 oC. Results By detection with HRM methods, 1 samples were confirmed to be mutant, 7 samples were confirmed to be heterozygous and the other 22 samples were all wild type in the lung cancer samples. 2 samples were confirmed to be heterozygous and the other 28 samples were all wild type in the normal samples. Conclusion The HRM method for detection of BIM deletion established in this study is a sensitive, accurate, simple and high throughput method.