Realization of solar‐driven aerobic organic transformation under atmospheric pressure raises the great challenge for efficiently activating O 2 by tailored photocatalysts. Guided by theoretical calculation, phosphate groups are used to induce the construction of ultrathin Co phthalocyanine/g‐C 3 N 4 heterojunctions (CoPc/P‐CN, ≈4 nm) via strengthened H‐bonding interfacial connection, achieving an unprecedented 14‐time photoactivity improvement for UV–vis aerobic 2,4‐dichlorophenol degradation compared to bulk CN by promoted activation of O 2 . It is validated that more • O 2 − radicals are produced through the improved photoreduction of O 2 by accelerated photoelectron transfer from CN to the ligand of CoPc and then to the abundant single Co–N 4 (II) catalytic sites, as endowed by the matched dimension, intimate interface even at the molecular level, and high CoPc dispersion of resulted heterojunctions. Interestingly, CoPc/P‐CN also exhibits outstanding photoactivities in the aerobic oxidation of aromatic alcohols. This work showcases a feasible route to realize efficient photocatalytic O 2 activation by exploiting the potential of ultrathin metal phthalocyanine (MPc) assemblies with abundant single‐atom sites. More importantly, a universal facile strategy of H‐bonding‐dominating construction of MPc‐involved heterojunctions is successfully established.

Covalent organic frameworks (COFs) are an emerging type of crystalline and porous photocatalysts for hydrogen evolution, however, the overall water splitting activity of COFs is rarely known. In this work, we firstly realized overall water splitting activity of β-ketoamine COFs by systematically engineering N-sites, architecture, and morphology. By in situ incorporating sub-nanometer platinum (Pt) nanoparticles co-catalyst into the pores of COFs nanosheets, both Pt@TpBpy-NS and Pt@TpBpy-2-NS show visible-light-driven overall water splitting activity, with the optimal H2 and O2 evolution activities of 9.9 and 4.8 μmol in 5 h for Pt@TpBpy-NS, respectively, and a maximum solar-to-hydrogen efficiency of 0.23%. The crucial factors affecting the activity including N-sites position, nano morphology, and co-catalyst distribution were systematically explored. Further mechanism investigation reveals the tiny diversity of N sites in COFs that induces great differences in electron transfer as well as reaction potential barriers.

Interface-modulated ultrathin Ni(ii) MOF/g-C3N4 heterojunctions exhibit greatly improved charge separation and, consequently, 18-fold photoactivity enhancement for the CO2RR.