Latest ArticlesThe selective conversion of CO2 and NH3 into valuable nitriles presents significant potential for CO2 utilization. In this study, we exploited the synergistic interplay between silicon and fluoride to augment the nickel-catalyzed reductive cyanation of aryl pseudohalides containing silyl groups, utilizing CO2 and NH3 as the CN source. Our methodology exhibited exceptional compatibility with diverse functional groups, such as alcohols, ketones, ethers, esters, nitriles, olefins, pyridines, and quinolines, among others, as demonstrated by the successful synthesis of 58 different nitriles. Notably, we achieved high yields in the preparation of bifunctionalized molecules, including intermediates for perampanel, derived from o-silylaryl triflates, which are well-known as aryne precursors. Remarkably, no degradation of substrates or formation of aryne intermediates were observed. Mechanistic studies imply that the formation of penta-coordinated silyl isocyanate intermediates is crucial for the key C–C coupling step and the presence of vicinal silyl group in the substrate is beneficial to further make this step kinetically favorable.
Traditional Pt/C electrode materials are prone to corrosion and detachment during H2S detection, leading to a decrease in fuel cell-type sensor performance. Here, a high-performance H2S sensor based on Pt loaded Ti3C2 electrode material with -O/-OH terminal groups was designed and prepared. Experimental tests showed that the Pt/Ti3C2 sensor has good sensitivity (0.162 µA/ppm) and a very low detection limit to H2S (10 ppb). After 90 days of stability testing, the response of the Pt/Ti3C2 sensor shows a smaller decrease of 2% compared to that of the Pt/C sensor (22.9%). Meanwhile, the sensor also has high selectivity and repeatability. The density functional theory (DFT) calculation combined with the experiment results revealed that the improved H2S sensing mechanism is attributed to the fact that the strong interaction between Pt and Ti3C2 via the Pt-O-Ti bonding can reduce the formation energy of Pt and Ti3C2, ultimately prolonging the sensor’s service life. Furthermore, the catalytic property of Pt can decrease the adsorption energy and dissociation barrier of H2S on Pt/Ti3C2 surface, greatly enhance the ability to generate protons and effectively transfer charges, realizing good sensitivity and high selectivity of the sensor. The sensor works at room temperature, making it very promising in the field of H2S detection in future.
The typical wastewater treatment is focused on the photocatalytic efficiency in the degradation of organic pollutants, with little attention to the involved selectivity which may correlate with toxicant residues. Herein, an electron localization strategy for specific O2 adsorption/activation enabled by photothermal/pyroelectric effect and in situ constructed active centers of single-atom Co and oxygen vacancy (Co-OV) on the Co/BiOCl-OV photocatalyst was developed for photocatalytic degradation of glyphosate (GLP) wastewater of high performance/selectivity. Under full-spectrum-light irradiation, a high GLP degradation rate of 99.8% with over 90% C‒P bond-breaking selectivity was achieved within 2 h, while effectively circumventing toxicant residues such as aminomethylphosphonic acid (AMPA). X-ray absorption spectroscopy and relevant characterizations expounded the tailored anchoring of Co single atoms onto the BiOCl-OV carrier and photothermal/pyroelectric effect. The oriented formation of more •O2− on Co/BiOCl-OV could be achieved with the Co-OV coupled center that had excellent O2 adsorption/activation capacity, as demonstrated by quantum calculations. The formed unique Co-OV active sites could largely decrease the C‒P bond-breaking energy barrier, thus greatly improving the selectivity toward the initial C‒P bond scission and the activity in subsequent conversion steps in the directional photocatalytic degradation of GLP. The electron localization strategy by in situ constructing the coupled active centers provides an efficient scheme and new insights for the low-toxic photodegradation of organic pollutants containing C‒X bonds.
Algal copper uptake (i.e., Cu bioavailability) in the euphotic zone plays a vital role in algal photosynthesis and respiration, affecting the primary productivity and the source and sink of atmospheric carbon. Algal Cu uptake is controlled by natural dissolved organic Cu (DOCu) speciation (i.e., complexed with the dissolved organic matter) that conventionally could be tested by model prediction or molecular-level characterizations in the lab, while DOCu uptake are hardly directly assessed. Thus, the new chemistry-biology insight into the mechanisms of the Cu uptake process in algae is urgent. The DOCu speciation transformation (organic DOCu to free Cu(Ⅱ) ions), enzymatic reduction-induced valence change (reduction of free Cu(Ⅱ) to Cu(Ⅰ) ions), and algal Cu uptake at the algae-water interface are imitated. Herein, an intelligent system with DOCu colorimetric sensor is developed for real-time monitoring of newly generated Cu(Ⅰ) ions. Deep learning with whole sample image-based characterization and powerful feature extraction capabilities facilitates colorimetric measurement. In this context, the Cu bioavailability with 7 kinds of organic ligands (e.g., amino acids, organic acids, carbohydrates) can be predicted by the mimetic intelligent biosensor within 15.0 min, i.e., the DOCu uptake and speciation is successfully predicted and streamlined by the biomimetic approach.
Proton exchange membrane water electrolysis (PEMWE) is a favorable technology for producing high-purity hydrogen under high current density using intermittent renewable energy. The performance of PEMWE is largely determined by the oxygen evolution reaction (OER), a sluggish four-electron reaction with a high reaction barrier. Nowadays, iridium (Ir)-based catalysts are the catalysts of choice for OER due to their excellent activity and durability in acidic solution. However, its high price and unsatisfactory electrochemical performance severely restrict the PEMWE’s practical application. In this review, we initiate by introducing the current OER reaction mechanisms, namely adsorbate evolution mechanism and lattice oxygen mechanism, with degradation mechanisms discussed. Optimized strategies in the preparation of advanced Ir-based catalysts are further introduced, with merits and potential problems also discussed. The parameters that determine the performance of PEMWE are then introduced, with unsolved issues and related outlooks summarized in the end.
Homogeneous C–H and C–X borylation via transition-metal-catalysis have undergone rapid development in the past decades and become one of the most practical methods for the synthesis of organoboron compounds. However, the catalysts employed in homogeneous catalysis are generally expensive, sensitive, and difficult to separate from the reaction mixture and reuse. With the rapid development of heterogeneous catalysis, heterogeneous C–H and C–X borylation have emerged as highly efficient and sustainable approaches towards the synthesis of organoboron compounds. This review aims to highlight the recent advances in the synthesis of organoboron compounds employing heterogeneous C–H and C–X borylation strategies. We endeavor to shed light on new perspectives and inspire further research and applications in this emerging area.
Developing efficient, non-toxic, and low-cost emitters is a key issue in promoting the applications of electrochemiluminescence (ECL). Among varied ECL emitters, polymeric emitters are attracting dramatically increasing interest due to tunable structure, large surface area, brilliant transfer capability, and sustainable raw materials. In this review, we present a general overview of recent advances in developing polymeric luminophores, including their structural and synthetic methodologies. Methods rooted in straightforward unique structural modulation have been comprehensively summarized, aiming at enhancing the efficiency of ECL along with the underlying kinetic mechanisms. Moreover, as several conjugated polymers were just discovered in recent years, promising prospects and perspectives have also been deliberated. The insight of this review may provide a new avenue for helping develop advanced conjugated polymer ECL emitters and decode ECL applications.
The intrinsic clustering behavior and kinetically sluggish conversion process of lithium polysulfides seriously limit the electrochemical reversibility of sulfur redox reactions in lithium-sulfur (Li-S) batteries. Here, we introduce molybdenum pentachloride (MoCl5) into the electrolyte which could coordinate with lithium polysulfides and inhibit their intrinsic clustering behavior, subsequently serving as an improved mediator with the bi-functional catalytic effect for Li2S deposition and activation. Moreover, the coordination bonding and accelerated conversion reaction can also greatly suppress the dissolution and shuttling of polysulfides. Consequently, such polysulfide complexes enable the Li-S coin cell to exhibit good long-term cycling stability with a capacity decay of 0.078% per cycle after 400 cycles at 2 C, and excellent rate performance with a discharge capacity of 589 mAh/g at 4 C. An area capacity of 3.94 mAh/cm2 is also achieved with a high sulfur loading of 4.5 mg/cm2 at 0.2 C. Even at -20 ℃, the modified cell maintains standard discharge plateaus with low overpotential, delivering a high capacity of 741 mAh/g at 0.2 C after 80 cycles. The low-cost and convenient MoCl5 additive opens a new avenue for the effective regulation of polysulfides and significant enhancement in sulfur redox conversion.
Achieving artificial simulations of multi-step energy transfer processes and conversions in nature remains a challenge. In this study, we present a three-step sequential energy transfer process, which was constructed through host-guest interactions between a piperazine derivative (PPE-BPI) with aggregation-induced emission (AIE) and cucurbit[7]uril (CB[7]) in water to serve as ideal energy donors. To achieve multi-step sequential energy transfer, we employ three distinct fluorescent dyes Eosin B (EsB), Sulforhodamine 101 (SR101), and Cyanine 5 (Cy5) as energy acceptors. The PPE-PBI-2CB[7]+EsB+SR101+Cy5 system demonstrates a highly efficient three-step sequential energy transfer mechanism, starting with PPE-PBI-2CB[7] and transferring energy successively to EsB, SR101, and finally to Cy5, with remarkable energy transfer efficiencies. More interestingly, with the progressive transfer of energy in the multi-step energy transfer system, the generation efficiency of superoxide anion radical (O2•–) increased gradually, which can be used as photocatalysts for selectively photooxidation of N-phenyltetrahydroisoquinoline in an aqueous medium with a high yield of 86% after irradiation for 18 h. This study offers a valuable investigation into the simulation of multi-step energy transfer processes and transformations in the natural world, paving the way for further research in the field.
Ferroptosis in combination with immune therapy emerges as a promising approach for cancer therapy. Herein, dual-responsive metal-polyphenol coordinated nanomedicines were developed for pH/glutathione (GSH)-responsive synergistic ferroptosis and immunotherapy. Our innovative strategy involves the development of a manganese-polyphenol coordinated nanostructure, leveraging the biocompatibility of bovine serum albumin (BSA) as a template to encapsulate the anticancer drug sorafenib. The tumor microenvironment (pH/GSH) prompts the disassembly of MnO2 and epigallocatechin gallate (EGCG), thereby releases the anticancer payload. Concurrently, MnO2 acts to deplete intracellular GSH, which in turn suppresses glutathione peroxidase activity, leading to an accumulation of lipid peroxides with cell ferroptosis. Additionally, the release of Mn2+ ions bolster the cyclic guanosine monophosphlic acid (GMP)-adenosine monophosphlic acid (AMP) synthase-stimulator of interferon gene (cGAS-STING) pathway, which, in conjunction with the immunogenic cell death (ICD) effect induced by tumor cell apoptosis, significantly promotes dendritic cell (DC) maturation and enhances the presentation of tumor antigens. This successively ignites a robust innate and adaptive immune response. Both in vitro and in vivo experiments have demonstrated that the concurrent administration of ferroptosis-inducing and immune-stimulating therapies can significantly inhibit tumor growth.