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In situ Raman spectroscopy reveals that CoPc facilitates the formation of disordered-CoOOH and high-valence-CoO2, endowing Co-MOF-74@CoPc with outstanding OER performance.

Correlating star-shaped donor-bridge-acceptor (DBA) molecular structures with intramolecular charge transfer (ICT) and intersystem crossing (ISC) is essential to their application in photocatalysis, photovoltaics, and organic light-emitting diodes (OLEDs). In this work, we report a systematic photophysical study on a series of star-shaped triazine-phenylene-carbazole DBA molecules with 0, 1, and 2 bridging phenylene units (pTCT-0P, pTCT-1P, pTCT-2P). Using a combination of steady-state and time-resolved spectroscopy with time-dependent density functional theory (TDDFT), we find that the bridge length can strongly impact the structural conformation, ICT, and ISC. Global target analysis of the time-resolved spectroscopy reveals that pTCT-0P has the most favorable ISC rate of 1.96 × 10

Synchrotron X-rays are widely used for material characterizations. However, they can also ionize atoms and molecules to damage and manipulate probed materials. We report here an X-ray-induced growth of copper hydroxide nitrate, Cu

Atomically dispersed catalysts such as single-atom catalysts have been shown to be effective in selectively oxidizing methane, promising a direct synthetic route to value-added oxygenates such as acetic acid or methanol. However, an important challenge of this approach has been that the loading of active sites by single-atom catalysts is low, leading to a low overall yield of the products. Here, we report an approach that can address this issue. It utilizes a metal-organic framework built with porphyrin as the linker, which provides high concentrations of binding sites to support atomically dispersed rhodium. It is shown that up to 5 wt% rhodium loading can be achieved with excellent dispersity. When used for acetic acid synthesis by methane oxidation, a new benchmark performance of 23.62 mmol·gcat-1·h-1 was measured. Furthermore, the catalyst exhibits a unique sensitivity to light, producing acetic acid (under illumination, up to 66.4% selectivity) or methanol (in the dark, up to 65.0% selectivity) under otherwise identical reaction conditions.

In the past decades, many attempts have been made to mimic the energy transfer (EnT) in photosynthesis, a key process occurring in nature that is of fundamental significance in solar fuels and sustainable energy. Metal-organic frameworks (MOFs), an emerging class of porous crystalline materials self-assembled from organic linkers and metal or metal cluster nodes, offer an ideal platform for the exploration of directional EnT phenomena. However, placing energy donor and acceptor moieties within the same framework with an atomistic precision appears to be a major synthesis challenge. In this work, we report the design and synthesis of a highly porous and photoactive N,N'-bicarbazole- and porphyrin-based mixed-ligand MOF, namely, NPF-500-H2TCPP (NPF = Nebraska porous framework; H2TCPP = meso-tetrakis(4-carboxyphenyl)porphyrin), where the secondary ligand H2TCPP is incorporated precisely through the open metal sites of the equatorial plane of the octahedron cage resulting from the underlying (4,8) connected network of NPF-500. The efficient EnT process from N,N'-bicarbazole to porphyrin in NPF-500-H2TCPP was captured by time-resolved spectroscopy and exemplified by photocatalytic oxidation of thioanisole. These results demonstrate not only the capability of NPF-500 as the scaffold to precisely arrange the donor-acceptor assembly for the EnT process but also the potential to directly utilize the EnT process for photocatalytic applications.

Here we report CdS quantum dot (QD) gels as highly efficient and unique photocatalysts for organic synthesis. We found that the photocatalytic activity of CdS QD gel was superior to phosphine oxide- and thiolate-capped CdS QDs for dehalogenation and a-amine arylation reactions because of the high accessibility of its surface sites to the substrates. In addition, we discovered the unique reactivity of CdS QD gel for ring-opening during α-amine arylation of tetrahydroisoquinoline via the reductive cleavage of C–N bonds. QD gels provide new opportunities in photocatalysis due to their unique surface interactions with the substrates or intermediates.

One-dimensional (1D) π-d-conjugated coordination polymers (CCPs) with charge delocalization have attracted significant attention due to their potential application in energy conversion and storage. However, the fundamental understanding of the correlation of their structural parameters with photophysical and photocatalytic properties remains underexplored. Herein, we report three novel Cu-node anthracene-based 1D π-d CCPs with systematic variation of steric groups (PhMeH) at the 9 and 10 position of anthracene (denoted as An

The spinel Co3O4 has emerged as a promising alternative to noble-metal-based electrocatalysts for electrochemical water electrolysis in alkaline medium. However, pure Co3O4, despite having high activity in anodic water oxidation, remains inactive toward the hydrogen evolution reaction (HER). Here, a Ni-doped Co3O4 (Co3-xNixO4) prepared by a simple method exhibits favorable HER activity and stability (>300 h, whether in 1 M KOH or the realistic 30 wt % KOH solution) after in situ electrochemical activation, outperforming almost all of the oxide-based electrocatalysts. More importantly, using the combination of in situ Raman spectroscopy and multiple high-resolution electron microscopy techniques, it is identified that the surface of Co3-xNixO4 crystals is reduced into intertwined CoyNi1-yO nanoparticles with highly exposed {110} reactive planes. Density functional theory calculations further prove that the Ni- doped CoO component in CoyNi1-yO plays a major role during the alkaline HER, because the introduction of Ni atoms into Co-O octahedra can optimize the electrical conductivity and tailor the adsorption/desorption free energies of H-ad and OHad intermediates.