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The physical properties of carbon materials can be altered by doping. For instance, the electronic properties of graphene can be modulated by controlling the substitutional doping of the carbon lattice with N. In addition, C–N bonding configurations with three ring types are recognized: pyridinic-N, pyrrolic-N, and graphitic-N. Controlling the type and relative density of various types of substitutional N is an important objective that requires an extremely high level of precision when the atomic lattice is constructed. This control can be accomplished only via bottom-up methods, such as chemical vapor deposition (CVD). The number of reports on N-doped graphene (NDG) grown via CVD has increased over the past decade, but a reliable wafer-scale production strategy that can realize the desired atomic-precision growth of NDG is still lacking. To identify the most promising strategies and analyze the consistency of the results published in the literature, we review the CVD growth and characterization of two-dimensional NDG and two of the most popular applications of NDG films: field-effect transistors and energy storage devices.

Carbonaceous materials are promising anodes for practical potassium-ion batteries, but fail to meet the requirements for durability and high capacities at low potentials. Herein, we constructed a durable carbon anode for high-energy-density K-ion full cells by a preferential pyrolysis strategy. Utilizing S and N volatilization from a π-π stacked supermolecule, the preferential pyrolysis process introduces low-potential active sites of sp 2 hybridized carbon and carbon vacancies, endowing a low-potential "vacancy-adsorption/intercalation" mechanism. The as-prepared carbon anode exhibits a high capacity of 384.2 mAh g À 1 (90 % capacity locates below 1 V vs. K/K + ), which contributes to a high energy density of 163 Wh kg À 1 of K-ion full battery. Moreover, abundant vacancies of carbon alleviate volume variation, boosting the cycling stability over 14 000 cycles (8400 h). Our work provides a new synthesis approach for durable carbon anodes of K-ion full cells with high energy densities.

Carbonaceous materials are promising anodes for practical potassium‐ion batteries, but fail to meet the requirements for durability and high capacities at low potentials. Herein, we constructed a durable carbon anode for high‐energy‐density K‐ion full cells by a preferential pyrolysis strategy. Utilizing S and N volatilization from a π–π stacked supermolecule, the preferential pyrolysis process introduces low‐potential active sites of sp2 hybridized carbon and carbon vacancies, endowing a low‐potential “vacancy‐adsorption/intercalation” mechanism. The as‐prepared carbon anode exhibits a high capacity of 384.2 mAh g−1 (90 % capacity locates below 1 V vs. K/K+), which contributes to a high energy density of 163 Wh kg−1 of K‐ion full battery. Moreover, abundant vacancies of carbon alleviate volume variation, boosting the cycling stability over 14 000 cycles (8400 h). Our work provides a new synthesis approach for durable carbon anodes of K‐ion full cells with high energy densities.

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