Biaxially‐Strained Phthalocyanine at Polyoxometalate@Carbon Nanotube Heterostructure Boosts Oxygen Reduction Catalysis

Abstract

Iron phthalocyanine (FePc) with unique FeN4 site has attracted increasing interests as a promising non‐precious catalyst. However, the plane symmetric structure endows FePc with undesired catalytic performance toward the oxygen reduction reaction (ORR). Here, we report a novel one‐dimensional heterostructured ORR catalyst by coupling FePc at polyoxometalate‐encapsulated carbon nanotubes (FePc‐{PW12}@NTs) using host‐guest chemistry. The encapsulation of polyoxometalates can induce a local tensile strain of single‐walled NTs to strengthen the interactions with FePc. Both the strain and curvature effects of {PW12}@NT scaffold tune the geometric structure and electronic localization of FeN4 centers to enhance the ORR catalytic performance. As expected, such a heterostructured FePc‐{PW12}@NT electrocatalyst exhibits prominent durability, methanol tolerance, and ORR activity with a high half‐wave potential of 0.90 V and a low Tafel slope of 30.9 mV dec−1 in alkaline medium. Besides, the assembled zinc‐air battery demonstrates an ultrahigh power density of 280 mW cm−2, excellent charge/discharge ability and long‐term stability over 500 h, outperforming that of the commercial Pt/C+IrO2 cathode. This study offers a new strategy to design novel heterostructured catalysts and opens a new avenue to regulate the electrocatalytic performance of phthalocyanine molecules.

Atomically dispersed Fe/Co–N–C and their composites for proton exchange membrane fuel cells

“…This molecule–substrate interaction was further discussed by Zhu et al . 133 Phosphotungstic acid is encapsulated in SWCNTs, and then FePc guest molecules are immobilized on the outer surface (FePc–{PW 12 }@NT) (Fig. 8g and h).…”

Room-Temperature Photoferroelectrics Semiconductor Driven by the Interlayer Confinement Effect

“…The confinement effect is currently at the forefront of research in various disciplines such as nanoscience, condensed matter physics, materials science, biomedicine, and so on. − When a substance is in a confined space, its physical and chemical properties undergo significant changes while bringing unexpected surprises. Compared to the successful application of the confinement effect in other fields, research on utilizing the confinement effect to regulate physical and chemical properties in OIHPs is still very rare.…”

MOF-Derived Cobalt Nanoparticles with Dispersed Iron Phthalocyanines as Bifunctional Oxygen Electrocatalysts

“…On the other hand, metal phthalocyanines (MPc) as molecular catalysts have garnered attention owing to their intrinsic M–N 4 active sites. − However, the activity of the M–N 4 sites in MPc remains unsatisfactory due to its symmetric electron distribution. Typically, the π–π interactions between MPc and the organic ligands or the carbon supports play a pivotal role in adjusting the electronic structure .…”

“…40 well as electrolytes during electrocatalysis. 41 Therefore, the rational design and preparation of MOF-derived nanomaterials as efficient bifunctional oxygen catalysts remain a significant challenge.…”