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Abstract Conventional organic photocatalysis typically relies on ultraviolet and short‐wavelength visible photons as the energy source. However, this approach often suffers from competing light absorption by reactants, products, intermediates, and co‐catalysts, leading to reduced quantum efficiency and side reactions. To address this issue, we developed novel organic two‐photon‐absorbing (TPA) photosensitizers capable of functioning under deep red and near‐infrared light irradiation. Three model reactions including cyclization, Sonogashira C_sp2−C_spcross‐coupling, and C_sp2−N cross‐coupling reactions were selected to compare the performance of the new photosensitizers under both blue (427 nm) and deep red (660 nm) light irradiation. The obtained results unambiguously prove that for reactions involving blue light‐absorbing reactants, products, and/or co‐catalysts, deep red light source resulted in better performance than blue light when utilizing our TPA photosensitizers. This work highlights the potential of our metal‐free TPA photosensitizers as a sustainable and effective solution to mitigate the competing light absorption issue in photocatalysis, not only expanding the scope of organic photocatalysts but also reducing reliance on expensive Ru/Ir/Os‐based photosensitizers. 

Abstract The burgeoning field of semiconductor‐mediated organic conversion is of paramount significance, with zinc indium sulfide (ZnIn₂S₄) emerging as a standout candidate owing to its benign nature, optimal bandgap, extensive light absorption spectrum, remarkable physicochemical properties, and straightforward synthesis. This review examines the latest breakthroughs and the trajectory of ZnIn₂S₄‐based photocatalysts in the realm of selective organic transformation. We start with a distinct overview of the intrinsic physical attributes of ZnIn₂S₄and the underlying mechanisms driving its efficacy in photocatalytic organic transformations. Subsequently, the preparation methods of ZnIn₂S₄are summarized. The main focus is the state‐of‐the‐art photocatalytic application of various ZnIn₂S₄‐based photocatalysts, such as redox reactions, the construction of C−C, C−S and S−S bonds, and the cleavage of C−O, C−C, and C=C bonds. In the conclusion part, we provide our perspectives on the prospective advancements and the remaining challenges that lie ahead in the optimization of ZnIn₂S₄‐based photocatalysts, with the ultimate goal of enhancing their efficacy for a diverse array of photosynthetic applications. It is anticipated to inspire the strategic engineering of ZnIn₂S₄and other semiconductor‐based photocatalysts for various artificial photosynthesis reactions. 

Abstract Efficient utilization of sunlight in photocatalysis is widely recognized as a promising solution for addressing the growing energy demand and environmental issues resulting from fossil fuel consumption. Recently, there have been significant developments in various near‐infrared (NIR) light‐harvesting systems for artificial photosynthesis and photocatalytic environmental remediation. This review provides an overview of the most recent advancements in the utilization of NIR light through the creation of novel nanostructured materials and molecular photosensitizers, as well as modulating strategies to enhance the photocatalytic processes. A special focus is given to the emerging two‐photon excitation NIR photocatalysis. The unique features and limitations of different systems are critically evaluated. In particular, it highlights the advantages of utilizing NIR light and two‐photon excitation compared to UV–visible irradiation and one‐photon excitation. Ongoing challenges and potential solutions for the future exploration of NIR light‐responsive materials are also discussed. 

Abstract Visible‐light‐driven C−C bond formation utilizing ketyl radical (C_ketyl) species has attracted increasing attention recently, as it provides a direct route for the synthesis of complex molecules. However, the most‐developed homogeneous photocatalytic systems for the generation and utilization of ketyl radicals usually entail noble metal‐based (e. g., Ru and Ir) photosensitizers, which suffer from not only high cost but also potential degradation and hence pose challenges in product separation and purification. In contrast, readily accessible, inexpensive, and recyclable semiconductors represent a class of attractive and alternative photocatalysts but remain much less explored for photocatalytic ketyl radical initiated C−C bond formation. This work demonstrates that a wide range of industrially important chemicals, including substituted chromanes and tertiary alcohols, can be produced on ZnIn₂S₄under visible light irradiation through intramolecular cyclization (C_ketyl−C_sp2) and intermolecular cross‐coupling (C_ketyl−C_sp3) reactions, respectively, using ketyl radicals. A suite of experimental studies aided by computational investigation were carried out to shed light on the mechanistic insights of these two types of ketyl radical initiated C−C coupling reactions on ZnIn₂S₄. 

Abstract Lysosomes are multifunctional organelles involved in macromolecule degradation, nutrient sensing, and autophagy. Live imaging has revealed lysosome subpopulations with dynamics and characteristic cellular localization. An as‐yet unanswered question is whether lysosomes are spatially organized to coordinate and integrate their functions. Combined with super‐resolution microscopy, we designed a small organic fluorescent probe—TPAE—that targeted lysosomes with a large Stokes shift. When we analyzed the spatial organization of lysosomes against mitochondria in different cell lines with this probe, we discovered different distance distribution patterns between lysosomes and mitochondria during increased autophagy flux. By usingSLC25A46mutation fibroblasts derived from patients containing highly fused mitochondria with low oxidative phosphorylation, we concluded that unhealthy mitochondria redistributed the subcellular localization of lysosomes, which implies a strong connection between mitochondria and lysosomes. 

Abstract As a process of cellular uptake, endocytosis, with gradient acidity in different endocytic vesicles, is vital for the homeostasis of intracellular nutrients and other functions. To study the dynamics of endocytic pathway, a membrane‐anchored pH probe,ECGreen, is synthesized to visualize endocytic vesicles under structured illumination microscopy (SIM), a super‐resolution technology. Being sensitive to acidity with increasing fluorescence at low pH,ECGreencan differentiate early and late endosomes as well as endolysosomes. Meanwhile, membrane anchoring not only improves the durability ofECGreen, but also provides an excellent anti‐photobleaching property for long‐time imaging with SIM. Moreover, by taking these advantages ofECGreen, a multidimensional analysis model containing spatial, temporal, and pH information is successfully developed for elucidating the dynamics of endocytic vesicles and their interactions with mitochondria during autophagy, and reveals a fast conversion of endosomes near the plasma membrane. 

Abstract Deuterium (D) labeling is of great value in organic synthesis, pharmaceutical industry, and materials science. However, the state‐of‐the‐art deuteration methods generally require noble metal catalysts, expensive deuterium sources, or harsh reaction conditions. Herein, noble metal‐free and ultrathin ZnIn₂S₄(ZIS) is reported as an effective photocatalyst for visible light‐driven reductive deuteration of carbonyls to produce deuterated alcohols using heavy water (D₂O) as the sole deuterium source. Defective two‐dimensional ZIS nanosheets (D‐ZIS) are prepared in a surfactant assisted bottom‐up route exhibited much enhanced performance than the pristine ZIS counterpart. A systematic study is carried out to elucidate the contributing factors and it is found that the in situ surfactant modification enabled D‐ZIS to expose more defect sites for charge carrier separation and active D‐species generation, as well as high specific surface area, all of which are beneficial for the desirable deuteration reaction. This work highlights the great potential in developing low‐cost semiconductor‐based photocatalysts for organic deuteration in D₂O, circumventing expensive deuterium reagents and harsh conditions. 

Under super-resolution imaging of probe PCV-1, we developed a new analytical assay named organelle ratiometric probing (ORP), which has successfully achieved quantitative analysis and efficient assessment of the viability of individual cells.