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The reduction of nitroaromatics is important in industrial wastewater treatment. However, the activity of an external catalyst is critical for the reaction. In this study, Au nanocrystals were anchored in situ on two-dimensional graphene oxide (GO), which had oxygen-rich groups on its surface. Oxygen-containing groups combined to form functional boron clusters through hydrogen bond interactions (BGO). The mild reducibility of a dodecahydrododecaborate anion cluster (closo-[B12H12]2−) made ultrafine Au nanocrystals uniformly disperse on GO (Au/BGO). 4-Nitrophenol and other nitro-aromatic hydrocarbons could be rapidly hydrogenated into aminoaromatic hydrocarbons by Au/BGO, and the hydrogenation efficiency was approximately 100%. It retained high catalytic activity after 16 catalytic cycles. Therefore, the proposed innovative preparation strategy and high catalytic activity indicate the advancement of closo-[B12H12]2− as a nucleation target for nanometals. This study provides a stable and efficient catalyst for the hydrogenation of nitroaromatics and an alternative approach for the preparation of supported nano-metals.

The reduction of nitroaromatics to aminoaromatics is essential for fine chemical production and effective sewage treatment. However, the activity of an external catalyst is essential for the reaction. In this study, Pd nanocrystals were anchored in situ on two-dimensional graphene oxide (GO), which acted as a catalyst support with high specific surface area. The oxygen-containing groups on the surface of GO bonded to the functionally rich boron clusters through hydrogen bonding interactions. A mildly reducible closed-dodecahydrododecaboric acid anion cluster (closo‑[B12H12]2–) was employed as the target site. The mild reducibility of closo‑[B12H12]2– resulted in a wide dispersion of ultrafine Pd nanocrystals on GO. Under ambient conditions, Pd/BGO rapidly hydrogenated nitroaromatics, such as 4-nitrophenol, to aminoaromatics with approximately 100% efficiency. Moreover, Pd/BGO retained its high catalytic activity for the hydrogenation/reduction of 4-nitrophenol after five catalytic cycles. Therefore, Pd/BGO could be a promising and economically viable candidate for various practical applications. The proposed innovative preparation strategy and highly efficient catalytic activity suggested the effective performance of closo‑[B12H12]2– as nanometal nucleation target sites. In addition to providing an alternate route for preparing supported nanometals, this study presents a stable and efficient catalyst for the hydrogenation of nitroaromatics.

Metal‑nitrogen‑carbon materials (M-N-C) have attracted much attention due to their low cost, high abundance, and efficient catalytic performance. Nevertheless, Fe-N-C materials are considered the most promising oxygen reduction reaction (ORR) catalysts for replacing noble metals. Ce is chemically active and has many metal valence states, and empty orbitals that can participate in coordination. On this basis, Fe, Ce-codoped catalyst was constructed in this study. The synergistic effect of the dual metal centers was verified, and a Fe, Ce-codoped nitrogen-doped carbon (FeCeNC) with six equal branch angles was proposed. The half-wave potential for the ORR catalyzed by FeCeNC is 0.855 V. As a rechargeable Zn-air battery cathode catalyst, FeCeNC exhibits excellent electrochemical performances, with an open-circuit voltage of 1.427 V, a maximum power density of 169.2 mW cm−2 and a stable cycling time of 80 h, demonstrating an excellent cycle performance.

In the present work, irregular Cu nanoparticle-decorated boron-carbon-nitrogen (Cu-BCN) nanosheets were successfully synthesized. A Cu-BCN dispersion was deposited on a bare glassy carbon electrode (GCE) to prepare an electrochemical sensor (Cu-BCN/GCE) for the detection of chloramphenicol (CAP) in the environment. Cu-BCN was characterized using high-resolution scanning transmission electron microscopy (HRSTEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, and X-ray photoelectron spectroscopy (XPS). The performance of the Cu-BCN/GCE was studied using electrochemical impedance spectroscopy (EIS), and its advantages were proven by electrode comparison. Differential pulse voltammetry (DPV) was used to optimize the experimental conditions, including the amount of Cu-BCN deposited, enrichment potential, deposition time, and pH of the electrolyte. A linear relationship between the CAP concentration and current response was obtained under the optimized experimental conditions, with a wide linear range and a limit of detection (LOD) of 2.41 nmol/L. Cu-BCN/GCE exhibited high stability, reproducibility, and repeatability. In the presence of various organic and inorganic species, the influence of the Cu-BCN-based sensor on the current response of CAP was less than 5%. Notably, the prepared sensor exhibited excellent performance in real-water samples, with satisfactory recovery.