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.

It is highly desired to promote the charge transfer and separation of WO3 for a highly efficient green process for photocatalytic aerobic selective alcohol oxidation. In this work, 2D WO3 nanoplates (2D WO) with enlarged surface area and favorable charge separation were successfully fabricated by the phase-separated hydrolysis–solvothermal method. The photoactivities of resulting 2D WO were improved by coupling with 2D g-C3N4 nanosheets (2D CN) to construct the 2D/2D type nanocomposites, and then, they were further enhanced by introducing silicate bridges between 2D WO and CN via a facile wet-chemical method. The amount-optimized Si–O-bridged 2D/2D g-C3N4/WO3 nanocomposite exhibited excellent photoactivity and high selectivity for aerobic selective alcohol oxidation by a 5-fold enhancement compared to bare WO under full-light irradiation, which is attributed to the significantly improved charge separation by the Z-scheme between 2D WO and 2D CN and facilitated charge transfer through the silicate bridges. The Z-scheme charge transfer mechanism was clearly verified by the single-wavelength photocurrent action spectra and single-wavelength fluorescence spectra. Moreover, the subsequent charge-carrier-induced photocatalytic reaction mechanism was investigated by the scavenger trapping and 18O2 isotope-labeled experiments. It is made evident that the photogenerated holes mainly dominate the selective alcohol oxidation. This present work has shown superior photocatalytic performance among all reported works on the WO3-based photocatalysts for aerobic selective alcohol oxidation to date. The research basis could be provided by this work for the synthesis of highly active WO3-based photocatalysts for aerobic selective organic oxidation.

It is highly desired to improve the visible‐light activity of g‐C3N4 for H2 evolution by constructing closely contacted heterojunctions with conductive polymers. Herein, a polymer nanocomposite photocatalyst with high visible‐light activity is fabricated successfully by coupling nanosized polypyrrole (NPPy) particles onto g‐C3N4 nanosheets through a simple wet‐chemical process, and its visible‐light activity is improved further by constructing Mg−O bridges between the NPPy and g‐C3N4. The amount‐optimized bridged nanocomposite displays an approximately ninefold improvement in visible‐light activity compared with g‐C3N4. On the basis of transient‐state surface photovoltage responses, photoluminescence spectra, .OH amount evaluation, and photoelectrochemical curves, it is concluded that the exceptional photoactivity can be attributed to the significantly promoted charge transfer and separation along with visible photosensitization from NPPy. Interestingly, it is confirmed that the promoted charge separation depends mainly on the excited high‐level electron transfer from g‐C3N4 to NPPy by single‐wavelength photocurrent action spectra. This work provides a feasible strategy for designing polymer nano‐heterojunction photocatalysts with exceptional visible‐light activities.

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