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.

In this study, a Z-type g-C 3 N 4 /BiOCl composite was synthesized by a one-step hydrothermal technique with varying loading amounts of graphene quantum dots (GQDs) to investigate their photocatalytic activity of N 2 fixation to NH 3 under simulated solar light irradiation. Experimental results showed that the photocatalytic activity of as-prepared GQDs/g-C 3 N 4 /BiOCl (GCNB) was significantly higher than those of pure g-C 3 N 4 and BiOCl, and the rate of NH 3 formation reached 1773.8 μmol/(hÁg cat ), which was 7.3 and 5.2 times greater than those of pure g-C 3 N 4 and BiOCl, respectively. After five cycles of experiments, the N 2 fixation ability of GCNB did not decrease obviously, indicating that GCNB had high photocatalytic stability. The excellent photocatalytic performance of GCNB was attributed to the broad light absorption range of BiOCl/ ultrathin g-C 3 N 4 binary materials and the unique photoelectronic properties of GQDs, which were loaded to form Z-type heterojunctions with a strong redox capability. A Z-type composite photocatalytic mechanism was proposed in this paper, which could significantly improve the charge separation efficiency and maintain a good redox capability. This study could provide an effective method for designing Z-type composite catalysts with high photocatalytic activity. Highlights 1. g-C 3 N 4 can enhance photocatalytic activity by slowing down the recombination of electron-hole pairs.2. GQDs is an excellent electron transport material sandwiched between g-C 3 N 4 and BiOCl.3. GQDs/g-C 3 N 4 /BiOCl composite material had the best performance of photocatalytic ammonia synthesis 4. The fixation mechanism of N 2 in Z-type heterojunction photocatalytic system was investigated.

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