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Photocatalytic reduction of carbon monoxide (CO), an increasingly available and low-cost feedstock that could benefit from CO 2 reduction, to high value-added multi-carbon chemicals, is significant for desirable carbon cycling, as well as high efficiency conversion and high density storage of solar energy. However, developing low cost but highly active photocatalysts with long-term stability for CO coupling and reduction remains a great challenge. Herein, by density functional theory (DFT) computations and taking advantage of the frustrated Lewis pairs (FLPs) concept, we identified a complex consisting of single boron (B) atom decorated on the optically active C 2 N monolayer ( i.e. , B/C 2 N) as an efficient and stable photocatalyst for CO reduction. On the designed B/C 2 N catalyst, CO can be efficiently reduced to ethylene (C 2 H 4 ) and propylene (C 3 H 6 ) both with a free energy increase of 0.22 eV for the potential-determining step, which greatly benefits from the pull–push function of the B–N FLPs composed of the decorating B atom and host N atoms. Moreover, the newly designed B/C 2 N catalyst shows significant visible light absorption with a suitable band position for CO reduction to C 2 H 4 and C 3 H 6 . All these unique features make the B/C 2 N photocatalyst an ideal candidate for visible light driven CO reduction to high value-added multi-carbon fuels and chemicals. 

The nitrogen electroreduction reaction (NRR) in aqueous solutions under ambient conditions represents an attractive prospect to produce ammonia, but the development of long-term stable and low-cost catalysts with high-efficiency and high-selectivity remains a great challenge. Herein, we investigated the potential of a new class of experimentally available boron-containing materials, i.e. , cubic boron phosphide (BP) and boron arsenide (BAs), as metal-free NRR electrocatalysts by means of density functional theory (DFT) calculations. Our results revealed that gas phase N 2 can be sufficiently activated on the B-terminated (111) polar surfaces of BP and BAs, and effectively reduced to NH 3 via an enzymatic pathway with an extremely low limiting potential (−0.12 V on BP and −0.31 V on BAs, respectively). In particular, the two proposed B-terminated (111) surfaces not only have a large active region for N 2 reduction, but also can significantly inhibit the competitive hydrogen evolution reaction, and thus have rather high efficiency and selectivity for the NRR. Therefore, cubic BP or BAs with mainly exposed (111) facets may serve as promising metal-free NRR catalysts with superior performance. 

Single‐atom catalysts (SACs) have attracted much attentions due to the advantages of high catalysis efficiency and selectivity. However, the controllable and efficient synthesis of SACs remains a significant challenge. Herein, we report a controlled one‐pot synthesis of nickel single atoms embedded on nitrogen‐doped carbon nanotubes (NiSA−N−CNT) and nitrogen‐doped graphene (NiSA−N−G). The formation of NiSA−N−CNT is due to the solid‐to‐solid rolling up mechanism during the high temperature pyrolysis at 800 °C from the stacked and layered Ni‐doped g‐C₃N₄, g‐C₃N₄−Ni structure to a tubular CNT structure. Addition of citric acid introduces an amorphous carbon source on the layered g‐C₃N₄−Ni and after annealing at the same temperature of 800 °C, instead of formation of NiSA−N−CNT, Ni single atoms embedded in planar graphene type supports, NiSA−N−G were obtained. The density functional theory (DFT) calculation indicates the introduction of amorphous carbon source substantially reduces the structure fluctuation or curvature of layered g‐C₃N₄‐Ni intermediate products, thus interrupting the solid‐to‐solid rolling process and leading to the formation of planar graphene type supports for Ni single atoms. The as‐synthesized NiSA−N−G with Ni atomic loading of ∼6 wt% catalysts shows a better activity and stability for the CO₂reduction reaction (CO₂RR) than NiSA−N−CNT with Ni atomic loading of ∼15 wt% due to the open and exposed Ni single atom active sites in NiSA−N−G. This study demonstrates for the first time the feasibility in the control of the microstructure of carbon supports in the synthesis of SACs.