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Photocatalytic oxygen reduction reaction (ORR) is an environmentally friendly and cost‐effective approach for H2O2 synthesis. However, the current photosynthesis system suffers from sluggish kinetics, rapid recombination of photoexcited charge carriers, and weak redox potentials, resulting in unsatisfactory solar‐to‐chemical conversion efficiency. Herein, a Z‐scheme heterojunction (UiO/IKCN) is constructed through coupling I−/K+ co‐doped g‐C3N4 (IKCN) with NH2‐UiO‐66, a typical metal‐organic framework material. Under visible light irradiation, the optimal UiO/IKCN exhibits exceptional H2O2 production rates in pure water (13.3 mM g−1 h−1) and in isopropanol solution (72.6 mM g−1 h−1), that is 48.4 times higher than pristine CN in isopropanol (1.5 mM g−1 h−1). A high apparent quantum yield of 10.28% at 420 nm is achieved by UiO/IKCN, surpassing most previously reported values. The dominating role of two‐electron ORR in H2O2 photosynthesis is elucidated in detail. The significantly enhanced photocatalytic activity can be attributed to the facilitated charge separation and Z‐scheme charge transfer, which are unambiguously verified by stable‐state surface photovoltage, transient photoluminescence, femtosecond transient absorption spectroscopy, in‐situ irradiated X‐ray photoelectron spectroscopy, and density functional theory calculations. This study represents the first exploration of H2O2 production using NH2‐UiO‐66 and provides insights into the rational design of Z‐scheme heterojunction for highly efficient photosynthesis. [ABSTRACT FROM AUTHOR]

Sensitizing molecular triplets by colloidal nanocrystals via triplet energy transfer is important for applications such as upconversion or organic synthesis. Typically two step triplet energy transfer (TET) are included in these applications: firstly the triplet energy stored in nanocrystals are extracted into surface ligands, and then the ligands further transfer triplet energy into molecules in bulk solution. Here we report one-step TET application from CsPbBr3 perovskite nanocrystals (NCs) to surface-anchored metalloporphyrin derivative molecules (MP). Compared to conventional two-step TET, the one-step TET mechanism possess lower energy loss and higher TET efficiency which is more generally implementable. In this scheme, photoexcitation of CsPbBr3 NCs leads to the sensitization of MP ligands triplets which efficiently emit phosphorescence. The enhanced light absorption of MP ligands and down-shifted photon emission can be useful in devices such as luminescent solar concentrators. [ABSTRACT FROM AUTHOR]

Cancerous genetic mutations result in a complex and comprehensive post-translational modification (PTM) dynamics, in which protein succinylation is well known for its ability to reprogram cell metabolism and is involved in the malignant evolution. Little is known about the regulatory interactions between succinylation and other PTMs in the PTM network. Here, we developed a conjoint analysis and systematic clustering method to explore the intermodification communications between succinylome and phosphorylome from eight lung cancer patients. We found that the intermodification coorperation in both parallel and series. Besides directly participating in metabolism pathways, some phosphosites out of mitochondria were identified as an upstream regulatory modification directing succinylome dynamics in cancer metabolism reprogramming. Phosphorylated activation of histone deacetylase (HDAC) in lung cancer resulted in the removal of acetylation and favored the occurrence of succinylation modification of mitochondrial proteins. These results suggest a tandem regulation between succinylation and phosphorylation in the PTM network and provide HDAC-related targets for intervening mitochondrial succinylation and cancer metabolism reprogramming. [ABSTRACT FROM AUTHOR]

The circ_UBR4 (hsa_circ_0010283) is a novel abnormally overexpressed circRNA in oxidized low-density lipoprotein (ox-LDL)-induced model of atherosclerosis (AS) in human vascular smooth muscle cells (VSMCs). However, its role in the dysfunction of VSMCs remains to be further investigated. Here, we attempted to explore its role in ox-LDL-induced excessive proliferation and migration in VSMCs by regulating Rho/Rho-associated coiled-coil containing kinase 1 (ROCK1), a therapeutic target of AS. Expression of circ_UBR4 and ROCK1 was upregulated, whereas miR-107 was downregulated in human AS serum and ox-LDL-induced VSMCs. Depletion of circ_UBR4 arrested cell cycle, suppressed cell viability, colony-forming ability, and migration ability, and depressed expression of proliferating cell nuclear antigen and matrix metalloproteinase 2 in VSMCs in spite of the opposite effects of ox-LDL. Notably, ROCK1 upregulation mediated by plasmid transfection or miR-107 deletion could counteract the suppressive role of circ_UBR4 knockdown in ox-LDL-induced VSMCs proliferation, migration, and cell cycle progression. In mechanism, miR-107 was identified as a target of circ_UBR4 to mediate the regulatory effect of circ_UBR4 on ROCK1. circ_UBR4 might be a contributor in human AS partially by regulating VSMCs’ cell proliferation, migration, and cell cycle progression via circ_UBR4/miR-107/ROCK1 pathway.

Linkage chemistry is an essential aspect to covalent organic framework (COF) applications; it is highly desirable to precisely modulate electronic structure mediated directly by linkage for efficient COF‐based photocatalytic hydrogen evolution, which however, remains substantially challenging. Herein, as a proof of concept, a collection of robust multicomponent pyrene‐based COFs with abundant donor‐acceptor (D−A) interactions has been judiciously designed and synthesized through molecularly engineering linkage for photogeneration of hydrogen. Controlled locking and conversion of linkage critically contribute to continuously regulating COFs' electronic structures further to optimize photocatalytic activities. Remarkably, the well‐modulated optoelectronic properties turn on the average hydrogen evolution rate from zero to 15.67 mmol g−1 h−1 by the protonated quinoline‐linked COF decorated with the trifluoromethyl group (TT‐PQCOF‐CF3). Using diversified spectroscopy and theoretical calculations, we show that multiple modifications toward linkage synergistically lead to the redistribution of charge on COFs with extended π‐conjugation and reinforced D−A effect, making TT‐PQCOF‐CF3 a promising material with significantly boosted carrier separation and migration. This study provides important guidance for the design of high‐performance COF photocatalysts based on the strategy of linkage‐mediated electronic structure modulation in COFs. [ABSTRACT FROM AUTHOR]

With strong electron–phonon coupling, self‐trapped excitons (STEs) are typically formed in perovskite materials, and radiative recombination of STEs can produce broadband emission with large Stokes shifts. STEs are essential to further improve the optoelectronic properties of materials. Surprisingly, 2D system is the edge case, with low even no self‐trapping barriers, leading to effortless formation of STEs. In this work, 2D strontium titanate (SrTiO3) with defects is prepared using supercritical carbon dioxide (SC CO2) and its carrier transport and transition are studied. The appearance of wide photoinduced positive absorption signals in the femtosecond transient absorption spectra is direct evidence for the formation of STEs. The presence of STEs is further supported by the increased Stokes shift and full width at half maximum in the steady‐state photoluminescence spectra. [ABSTRACT FROM AUTHOR]

The inclusion of colloidal particles into 3D porous constructs to realize heterostructure ensembles enhances surface interactions and energy transfer that can transform the catalytic properties of conventional catalysts. However, assembling hydrophobic colloidal nanoparticles within hydrophilic 3D porous matrices to create tailored heterostructures and catalytic properties is particularly challenging. Here, a modified ligand grafting method is presented to spontaneously assemble CdS inorganic colloidal quantum dots within a metal‐organic framework (MOF) derived porous framework for efficient photocatalytic CO2 reduction. The grafted long chain molecular ligands effectively suppress phase separation and endow a molecular‐recognition effect to form ordered assembly microstructures. The proof‐of‐concept assembly of CdS and Prussian blue analogues (PBA) derived Co3O4 facilitates a high density of heterojunctions formation, improving charge transfer and extended lifetimes of photo‐induced electrons. Consequently, CdS/Co3O4 assembly exhibits exceptionally active and stable photocatalytic CO2 reduction activity, with a CO production rate of 73.9 µmol g−1 h−1 and CO selectivity of 98.9%. Importantly, the ligand grafting method can be generalized to achieve spontaneous assembly of quantum dots within various metal organic framework derived porous scaffolds. This work provides a rational strategy for precise self‐assembly of colloidal nanoparticles within porous microstructures, allowing tailored heterointerfaces for functional materials and applications. [ABSTRACT FROM AUTHOR]

Two‐dimensional semiconductor‐based nanomaterials have shown to be an effective substrate for Surface‐enhanced Raman Scattering (SERS) spectroscopy. However, the enhancement factor (EF) tends to be relatively weak compared to that of noble metals and does not allow for trace detection of molecules. In this work, we report the successful preparation of two‐dimensional (2D) amorphous non‐van der Waals heterostructures MoO3‐x/GDYO nanomaterials using supercritical CO2. Due to the synergistic effect of the localized surface plasmon resonance (LSPR) effect and the charge transfer effect, it exhibits excellent SERS performance in the detection of methylene blue (MB) molecules, with a detection limit as low as 10−14 M while the enhancement factor (EF) can reach an impressive 2.55×1011. More importantly, the chemical bond bridging at the MoO3‐x/GDYO heterostructures interface can accelerate the electron transfer between the interfaces, and the large number of defective surface structures on the heterostructures surface facilitates the chemisorption of MB molecules. And the charge recombination lifetime can be proved by a ~1.7‐fold increase during their interfacial electron‐transfer process for MoO3‐x/GDYO@MB mixture, achieving highly sensitive SERS detection. [ABSTRACT FROM AUTHOR]