Hierarchical Porous Carbons for High‐Rate Aqueous Supercapacitors: Tuning Pore Sizes by Molecular Design of Carbon Dots as Self‐Templates

ABSTRACT Rational pore‐size regulation is central to high‐performance electric double‐layer capacitors, yet carbon dots (CDs) self‐templating often yields overly micropore‐dominated carbons with limited high‐rate capability. Here, we tailor CDs by combining polyethyleneimine with four organic acids and convert them into porous carbons, eliminating high‐temperature corrosive chemical activation. Systematic porosimetry reveals a direct link between CDs molecular architecture and the resulting pore‐size distributions. Notably, a mesopore‐enriching pathway is identified, allowing hierarchical micro/mesoporosity. The optimized sample (PC‐PMDA) delivers 582 F g −1 at 1 A g −1 and retains 475 F g −1 at 60 A g −1 with an IR drop of 0.09 V. At a practical mass loading of 10 mg cm −2 , 78% of the capacity (relative to that at low loading) is still retained. This study provided a mechanistic picture of pore generation by CDs self‐templating.