Highly efficient noble-metal-free electrocatalysts for oxygen reduction reaction (ORR) are essential to reduce the costs of fuel cells and metal–air batteries. Herein, a single-atom Ce–N–C catalyst, constructed of atomically dispersed Ce anchored on N-doped porous carbon nanowires, is proposed to boost the ORR. This catalyst has a high Ce content of 8.55 wt % and a high activity with ORR half-wave potentials of 0.88 V in alkaline media and 0.75 V in acidic electrolytes, which are comparable to widely studied Fe–N–C catalysts. A Zn–air battery based on this material shows excellent performance and durability. Density functional theory calculations reveal that atomically dispersed Ce with adsorbed hydroxyl species (OH) can significantly reduce the energy barrier of the rate-determining step resulting in an improved ORR activity.

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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., MoFe 2 O 4 and CoFe 2 O 4 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.

Electrochemical reduction of carbon dioxide (CO2) to ethanol is a promising strategy for global warming mitigation and resource utilization. However, due to the intricacy of C─C coupling and multiple proton–electron transfers, CO2‐to‐ethanol conversion remains a great challenge with low activity and selectivity. Herein, it is reported a P‐doped graphene aerogel as a self‐supporting electrocatalyst for CO2 reduction to ethanol. High ethanol Faradaic efficiency (FE) of 48.7% and long stability of 70 h are achieved at −0.8 VRHE. Meanwhile, an outstanding ethanol yield of 14.62 µmol h−1 cm−2 can be obtained, outperforming most reported electrocatalysts. In situ Raman spectra indicate the important role of adsorbed *CO intermediates in CO2‐to‐ethanol conversion. Furthermore, the possible active sites and optimal pathway for ethanol formation are revealed by density functional theory calculations. The graphene zigzag edges with P doping enhance the adsorption of *CO intermediate and increase the coverage of *CO on the catalyst surface, which facilitates the *CO dimerization and boosts the EtOH formation. In addition, the hierarchical pore structure of P‐doped graphene aerogels exposes abundant active sites and facilitates mass/charge transfer. This work provides inventive insight into designing metal‐free catalysts for liquid products from CO2 electroreduction.

The selective hydrogenation of Ar−CC in the presence of Ar−NO 2 is a long-standing challenge because of the uncontrolled nonselective nature of hydrogenation. In this study, the core−shell nanocatalyst ZIF-

A four‐step route for the synthesis of 5‐azatetracene (benzo[b]acridine) has been developed, employing a base‐catalysed Friedlander condensation reaction between 3‐amino‐2‐napthaldehyde and cyclohexanone as the key step followed by dehydrogenation of the intermediate. The optical and electrochemical properties of the 5‐azatetracene were investigated by UV‐vis and photoluminescence spectroscopy, and by cyclic voltammetry and compared with those of tetracene. It is found that 5‐azatetracene shows broader absorption in the visible region than tetracene, exhibits a higher luminescence quantum efficiency, and possesses a lower‐lying LUMO level and smaller HOMO‐LUMO band gap. Time‐resolved PL spectroscopy was used to elucidate the reasons for the more efficient luminescence of 5‐azatetracene. Field‐effect transistor measurements revealed the ambipolar nature of charge transport in 5‐azatetracene.

In this work, a visible-light-controlled drug release platform was constructed for localized and prolonged drug release based on two-layer titania nanotubes (TNTs) fabricated using by an in situ voltage up-anodization process. The visible-light photocatalytic activity is improved by loading Ag onto the TNTs by NaBH4 reduction. Then, the TNTs containing Ag nanoparticles were modified with dodecanethiol (NDM) to create a hydrophobic layer. To demonstrate the visible-light-controlled drug release, the Zn2+ release behavior of the samples was investigated. In the initial 12 h, TNTs without NDM displayed a faster release rate with 29.4% Zn2+ release, which was more than three times that of the TNTs with NDM (8.7% Zn2+ release). Upon visible-light illumination, drug release from the sample coated with NDM was shown to increase due to the photocatalytic decomposition of NDM. The amount of released Zn2+ for this sample increased up to 71.9% within 12 h, indicating visible-light-controlled drug release. This drug release system may exhibit promising application as a localized, prolonged drug delivery platform.

Post‐combustion flue gas (mainly containing 5–40% CO2 balanced by N2) accounts for about 60% global CO2 emission. Rational conversion of flue gas into value‐added chemicals is still a formidable challenge. Herein, this work reports a β‐Bi2O3‐derived bismuth (OD‐Bi) catalyst with surface coordinated oxygen for efficient electroreduction of pure CO2, N2, and flue gas. During pure CO2 electroreduction, the maximum Faradaic efficiency (FE) of formate reaches 98.0% and stays above 90% in a broad potential of 600 mV with a long‐term stability of 50 h. Additionally, OD‐Bi achieves an ammonia (NH3) FE of 18.53% and yield rate of 11.5 µg h−1 mgcat−1 in pure N2 atmosphere. Noticeably, in simulated flue gas (15% CO2 balanced by N2 with trace impurities), a maximum formate FE of 97.3% is delivered within a flow cell, meanwhile above 90% formate FEs are obtained in a wide potential range of 700 mV. In‐situ Raman combined with theory calculations reveals that the surface coordinated oxygen species in OD‐Bi can drastically activate CO2 and N2 molecules by selectively favors the adsorption of *OCHO and *NNH intermediates, respectively. This work provides a surface oxygen modulation strategy to develop efficient bismuth‐based electrocatalysts for directly reducing commercially relevant flue gas into valuable chemicals.