Investigation of Electrocatalytic Hydrogen Evolution Reaction (HER) Efficiencies of Phthalocyanines/Carbon‐Boron Quantum Dots Nanoconjugates

We developed highly efficient electrocatalysts for hydrogen evolution through the noncovalent integration (via electrostatic and π ‐ π interactions) of tetra‐hydroxythioethyl‐substituted metal‐free (H 2 Pc) and cobalt(II) phthalocyanines (CoPc) with boron‐doped carbon quantum dots (CBQdot). Incorporation of CBQdots greatly enhanced the molecular organization and uniformity of H 2 Pc and CoPc through strong interfacial interactions. π – π stacking, hydrogen bonding, and coordination between cobalt center and CBQdot surface groups led to well‐ordered nanoconjugate systems. Raman analyses showed a decreased D / G ratio, particularly in CoPc/CBQdot, indicating defect passivation and improved interfacial ordering. SEM, EDX, and AFM results demonstrated reduced aggregation, smaller uniformly dispersed particles, and smoother, more continuous film morphologies. The hybrid CoPc/CBQD catalyst demonstrated exceptional HER activity in acidic media, significantly outperforming the CBQDots, H 2 Pc, and CoPc. Remarkably, the hybrid catalyst demonstrated superior hydrogen evolution reaction (HER) activity in acidic media, achieving a low overpotential of 434 mV at 10 mA cm −2 current density with a favorable Tafel slope of 124 mV dec −1 . This enhanced performance originates from the synergistic π ‐ π stacking interactions between the phthalocyanine core and the carbon quantum dots, which effectively modulates the catalyst's active surface area. Our findings present a technologically viable approach for developing noble‐metal‐free HER catalysts. The strategic design of these π ‐ π stacked nanoconjugates offers a promising pathway for efficient hydrogen production, addressing both performance and cost considerations in renewable energy applications.