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In this work, a facile ultrasonic method for the fabrication of AgCl quantum dots (AgCl QDs) with an average diameter of about 2.5[Formula: see text]nm was reported for the first time. The material was analyzed by various techniques. In addition, effects of material’s size on its photocatalytic activities were studied. Results suggested that the AgCl QDs exhibited excellent photocatalytic activity to degrade Rhodamine B (RhB) and tetracycline (TC) under visible light illumination, and the degradation rate of RhB (TC) had reached up to 96.6% (72.2%) in 20 min, which was higher than that of AgCl nanoparticles (23[Formula: see text]nm) and AgCl nanospheres (114[Formula: see text]nm), respectively. Besides, the band gap of the material was increased when the size of material decreased from 23[Formula: see text]nm to 2.5[Formula: see text]nm. The significantly improved photocatalytic performance and increased band gap of AgCl QDs were mainly related to the quantum size effects of AgCl, which results in the more electron fluctuation in quantized energy levels and the lower recombination of electrons and holes.

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The discovery of extremely effective heteroatom dopant catalysts for electrochemical reduction reactions is crucial for ambient nitrogen fixation. In this paper, we investigated nitrogen and boron doped biomass carbon as an effective electrocatalyst for nitrogen reduction reaction (NRR), where the N, B content ratio, and pyrolysis temperature were optimized to improve N2 adsorption and N≡N cleavage. The resulting 600ACNB‐213 exhibits outstanding improvement in fixing N2 to ammonia with a high ammonia production rate (41 μg h−1 mg−1 at −1 V vs. RHE), outperforming other metals and carbon‐based materials and even being superior to noble‐metal‐based catalysts. Besides, there indicates good stability through six cycles of testing. Experiments and analyses demonstrated that pyridinic‐N and BC2O were active sites for ammonia synthesis and that their contents' ratio was critical for enhancing ammonia production on N, B doped carbon. These sites can enhance step‐by‐step catalytic reactions through rapid electron transfer processes by strengthening the conductivity of carbon‐based materials with dopants, substantially improving the overall catalytic performance. This research suggests that designing carbon co‐doped with N, B for effective N2 reduction electrocatalysts has a significant potential.

Heterojunction construction and morphology control have always been considered effective ways to promote the capability of photocatalysts. In this work, BiOI x Br y , S-type heterojunction photocatalysts with metallic Bi nanoparticles, were synthesized in situ using a solvothermal method, and the influence of reaction temperature (180 °C–220 °C) and dopant doping amount on the catalysts’ microscopic morphology, structure, and catalytic properties were researched. Study results revealed the 1:1 BiOI x Br y synthesized at 200 °C exhibited the optimum behavior in CO2 reduction. Its catalytic CO2 reduction to CH3OH was 932.88 μmol gcat −1 and C2H5OH was 324.46 μmol gcat −1 under the analog light source for 8 h, which was approximately 1.92 and 1.49 times higher than that of BiOI-200 °C, respectively. The reinforced catalytic properties are probably attributed to the synergistic effect between metallic Bi nanoparticles and BiOI x Br y heterojunction. Thanks to the SPR effect of in situ metallic Bi, the catalysts’ photocarrier separation efficiency is facilitated. Additionally, the heterojunction formation contributes to that trend and more importantly, preserves the charge carriers with strong redox capacity in BiOI x Br y , proving product selectivity. We also present a potential electron transfer mechanism involved in the BiOI x Br y photocatalytic CO2 reduction based on the characterization analysis and experimental results.