Electrochemical CO 2 reduction (CO 2 R) is a sustainable way of producing carbon-neutral fuels, yet the efficiency is limited by its sluggish kinetics and complex reaction pathways. Developing active, selective, and stable CO 2 R electrocatalysts is challenging and entails intelligent material structure design and tailoring. Here we show a graphdiyne/graphene (GDY/ G) heterostructure as a 2D conductive scaffold to anchor monodispersed cobalt phthalocyanine (CoPc) and reduce CO 2 with an appreciable activity, selectivity, and durability. Advanced characterizations, e.g., synchrotron-based X-ray absorption spectroscopy (XAS), and density functional theory (DFT) calculation disclose that the strong electronic coupling between GDY and CoPc, together with the high surface area, abundant reactive centers, and electron conductivity provided by graphene, synergistically contribute to this distinguished electrocatalytic performance. Electrochemical measurements revealed a high FE CO of 96% at a partial current density of 12 mA cm −2 in a H-cell and an FE CO of 97% at 100 mA cm −2 in a liquid flow cell, along with a durability over 24 h. The per-site turnover frequency of CoPc reaches 37 s −1 at −1.0 V vs RHE, outperforming most of the reported phthalocyanine-and porphyrin-based electrocatalysts. The usage of the GDY/G heterostructure as a scaffold can be further extended to other organometallic complexes beyond CoPc. Our findings lend credence to the prospect of the GDY/G hybrid contributing to the design of single-molecule dispersed CO 2 R catalysts for sustainable energy conversion.

Graphdiyne (GDY), a 2D carbon allotrope, is predicted to possess high carrier mobility and an intrinsic bandgap. However, the controlled synthesis of mono‐ or few‐layer GDY with good crystallinity remains challenging because of the instability of the monomers. Herein, a rapid and catalyst‐free synthetic method is presented for few‐layer GDY involving the use of a solid/liquid interface and a microwave‐induced temperature gradient. Sodium chloride, which can absorb microwave energy, is used as the solid substrate in a nonabsorbing solvent. A temperature gradient is formed at the solid/liquid interface under microwave irradiation, facilitating the cross‐coupling reaction of monomers at the solid surface and stabilizing the monomers in the bulk solution. Few‐layer GDY with an average thickness of less than 2 nm, a field‐effect mobility of 50.1 cm2 V−1 s−1, and p‐type characteristics is successfully obtained. This wet chemical approach may be extended to the synthesis of other few‐layered 2D materials with improved quality.

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