A facile and cost-effective method is developed to produce nitrogen (N)-doped holey graphene nanosheets (NHGNSs) using rapid heating under an NO atmosphere. This is a single-step and residual-free process wherein the holey structure and N doping are simultaneously created. In this study, we employ three kinds of additives, namely graphene (GNSs), holey graphene (HGNSs), and NHGNSs, in activated carbon (AC) electrodes. The conventional GNS additive though improves electronic conductivity of the AC electrode greatly hinders the ionic conductivity, decreasing supercapacitive performance in propylene carbonate electrolyte. HGNSs with large accessible surface area and efficient ion transport pathways outperform the GNS electrode additive. The NHGNSs, owing to the dual benefits of the holey structure and high electronic conductivity, is the best additive for the AC electrode. The NHGNSs improve electrode wettability toward electrolyte, enhance ion diffusion, and reduce interfacial contact resistance, thereby promoting rate capability of the AC cell. In addition, the effects of electrode additives on reliability of AC cells are investigated for the first time. The NHGNSs effectively suppress the leakage current and electrode gassing under operation. An effective strategy to improve charge-discharge performance, cyclability, and reliability of electric double-layer supercapacitors is proposed.

开发了一种简便且具有成本效益的方法，以在 NO 气氛下使用快速加热来生产氮 (N) 掺杂的多孔石墨烯纳米片 (NHGNS)。这是一个单步无残留工艺，其中孔结构和 N 掺杂同时产生。在这项研究中，我们在活性炭 (AC) 电极中使用了三种添加剂，即石墨烯 (GNSs)、多孔石墨烯 (HGNSs) 和 NHGNSs。传统的 GNS 添加剂虽然提高了交流电极的电子电导率，但极大地阻碍了离子电导率，降低了碳酸丙烯酯电解质中的超级电容性能。具有大的可及表面积和有效的离子传输途径的 HGNS 优于 GNS 电极添加剂。NHGNSs由于具有多孔结构和高电子导电性的双重优势，是交流电极的最佳添加剂。NHGNSs提高了电极对电解质的润湿性，增强了离子扩散，降低了界面接触电阻，从而提高了交流电池的倍率性能。此外，首次研究了电极添加剂对交流电池可靠性的影响。NHGNS 有效地抑制了运行中的漏电流和电极析气。提出了一种提高双电层超级电容器充放电性能、可循环性和可靠性的有效策略。首次研究了电极添加剂对交流电池可靠性的影响。NHGNS 有效地抑制了运行中的漏电流和电极析气。提出了一种提高双电层超级电容器充放电性能、可循环性和可靠性的有效策略。首次研究了电极添加剂对交流电池可靠性的影响。NHGNS 有效地抑制了运行中的漏电流和电极析气。提出了一种提高双电层超级电容器充放电性能、可循环性和可靠性的有效策略。