Bimodal Pore Engineering of Mesoporous Carbon onto Ti3C2T x via a Soft–Hard Templating Route for Highly Durable Potassium-Ion Batteries

Two-dimensional mesoporous carbon materials with tailored porosity and robust interfacial coupling are pivotal for potassium-ion batteries, yet the precise construction of bimodal pores remains a critical bottleneck. Herein, we propose an interfacial assembly strategy for the in situ growth of N,P-co-doped bimodal mesoporous carbon onto Ti3C2Tx MXene (D-NMC/Ti3C2Tx) via a phytic acid (PA)-mediated soft–hard dual-templating route. Both theoretical and experimental results demonstrate that PA serves as a molecular bridge, reinforcing hydrogen-bonding interactions to orchestrate the coassembly of P123, SiO2 nanospheres, and 2,6-diaminopyridine onto the functionalized Ti3C2Tx surface. Attributed to the unique design, D-NMC/Ti3C2Tx delivers a high reversible capacity of 303.6 mAh g–1 at 0.1 A g–1 over 200 cycles and retains 148.3 mAh g–1 after 3500 cycles at 1.0 A g–1. XPS depth profiling reveals that the enhanced performance originates from a stable inorganic-rich solid electrolyte interphase that maintains electrode integrity. This work offers a promising strategy for designing advanced carbon-based electrodes.