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Oxygenated volatile organic compounds (OVOCs), emitted in large quantities by the chemical industry, are a major contributor to the formation of ozone and subsequent particulate matter. For the efficient catalytic oxidation of OVOCs, the challenges of molecular activation and intermediate inhibition remain. The construction of bifunctional active sites with specific structures offers a promising way to overcome these problems. Here, the Pd@Layered-CoOx/MFI bifunctional catalyst with core–shell active sites was rationally fabricated though a two-step ligand pyrolysis method, which exhibits a superb oxidation efficiency toward ethyl acetate (EA). Over this, 13.4% of EA (1000 ppm) can be oxidized at just 140 °C with a reaction rate of 13.85 mmol·gPd–1·s–1, around 176.7 times higher than that of the conventional Pd-CoOx/MFI catalyst. The electronic coupling of the Pd–Co pair promotes the electron back-donation from Pd nanoparticles to the layered CoOxshell and facilitates the formation of Pd2+species, which greatly enhances the adsorption and activation of the electron-rich C═O bond of the EA molecules. In addition, the synergy of these core–shell Pd@Layered-CoOxsites accelerates the activation and transformation of *O species, which inhibit the formation of acetaldehyde and ethanol byproducts, ensuring the rapid total oxidation of EA molecules viathe Mars–van Krevelen mechanism. This work established a solid foundation for exploring robust bifunctional catalysts for deep OVOC purification.

Herein we report the discovery of an azabicyclo[2.1.1]hexane piperazinium methanesulfonate salt from an unexpected rearrangement reaction in the preparation of ligand-directed degraders (LDDs). This bench-stable compound was found to be a versatile electrophile in a ring-opening reaction with various types of nucleophiles. Its utility as a versatile medicinal chemistry building block is further demonstrated in the synthesis of an LDD compound targeting degradation of the androgen receptor.

ABSTRACTIntroductionHematopoietic progenitor kinase 1 (HPK1), a 97-kDa serine/threonine Ste20-related protein kinase, functions as an intracellular negative regulator, primarily in hematopoietic lineage cells, where it regulates T cells, B cells, dendritic cells, and other immune cells. Loss of HPK1 kinase activity results in exacerbated cytokine secretion, enhanced T cell signaling, improved viral clearance, and thus increased restraint of tumor growth. These findings highlight HPK1 as a promising target for immuno-oncology treatments, culminating in the advancement of candidate compounds targeting HPK1 to clinical trials by several biotech enterprises.Areas coveredThrough searching PubMed, Espacenet-patent search, and clinicaltrials.gov, this review provides a comprehensive analysis of HPK1, encompassing its structure and roles in various downstream signaling pathways, the consequences of constitutive activation of HPK1, and potential therapeutic strategies to treat HPK1-driven malignancies. Moreover, the review outlines the patents issued for small molecule inhibitors and clinical investigations of HPK1.Expert opinionTo enhance the success of tumor immunotherapy in clinical trials, it is important to develop protein degraders, allosteric inhibitors, and antibody-drug conjugates based on the crystal structure of HPK1, and to explore combination therapy approaches. Although several challenges remain, the development of HPK1 inhibitors display promising in preclinical and clinical studies.

The widespread presence of formaldehyde (HCHO) pollutant has aroused significant environmental and health concerns. The catalytic oxidation of HCHO into CO2and H2O at ambient temperature is regarded as one of the most efficacious and environmentally friendly approaches; to achieve this, however, accelerating the intermediate formate species formation and decomposition remains an ongoing obstacle. Herein, a unique tandem catalytic system with outstanding performance in low-temperature HCHO oxidation is proposed on well-structured Pd/Mn3O4–MnO catalysts possessing bifunctional catalytic centers. Notably, the optimized tandem catalyst achieves complete oxidation of 100 ppm of HCHO at just 18 °C, much better than the Pd/Mn3O4(30%) and Pd/MnO (27%) counterparts as well as other physical tandem catalysts. The operandoanalyses and physical tandem investigations reveal that HCHO is primarily activated to gaseous HCOOH on the surface of Pd/Mn3O4and subsequently converted to H2CO3on the Pd/MnO component for deep decomposition. Theoretical studies disclose that Pd/Mn3O4exhibits a favorable reaction energy barrier for the HCHO → HCOOH step compared to Pd/MnO; while conversely, the HCOOH → H2CO3step is more facilely accomplished over Pd/MnO. Furthermore, the nanoscale intimacy between two components enhances the mobility of lattice oxygen, thereby facilitating interfacial reconstruction and promoting interaction between active sites of Pd/Mn3O4and Pd/MnO in local vicinity, which further benefits sustained HCHO tandem catalytic oxidation. The tandem catalysis demonstrated in this work provides a generalizable platform for the future design of well-defined functional catalysts for oxidation reactions.

As a generally existing component in industrial streams, H2O usually inhibits the catalytic degradation efficiency of volatile organic compounds (VOCs) greatly. Here, we propose a novel strategy that accelerates the H2O dissociation and facilitates positive feedbacks during VOC oxidation by fabricating citric acid (CA)-assisted Pt(K)–Mn2O3/SiO2(Pt–Mn/KS-xCA). Results reveal that the complexation of carboxyl groups of citric acid with Mn cations leads to the formation of small Mn2O3(4.1 ± 0.2 nm) and further enhances the Mn–O–Pt interaction (strengthened by the Si–O–Mn interaction), which can transfer more electrons from Pt–Mn/KS-6CA to H2O, thus facilitating its breaking of covalent bonds. It subsequently produces abundant surface hydroxyl groups, improving the adsorption and activation abilities of acetone reactant and ethanol intermediate. Attributing to these, the acetone turnover frequency value of Pt–Mn/KS-6CA is 1.8 times higher than that of Pt–Mn/KS at 160 °C, and this multiple changes to 6.3 times in the presence of H2O. Remarkably, acetone conversion over Pt–Mn/KS-6CA increases by up to 14% in the presence of H2O; but it decreases by up to 26% for Pt–Mn/KS due to its weak dissociation ability and high adsorption capacity toward H2O. This work sheds new insights into the design of highly efficient catalytic materials for VOC degradation under humid conditions.

Amorphous zerovalent iron (AZVI) has gained considerable attention due to its remarkable reactivity, but there is limited research on sulfidated amorphous zerovalent iron (SAZVI) and the influence of different sulfur precursors on its reactivity remains unclear. In this study, SAZVI materials with an amorphous structure were synthesized using various sulfur precursors, resulting in significantly increased specific surface area and hydrophobicity compared to AZVI. The Cr(VI) removal efficiency of SAZVI-Na2S, which exhibited the most negative free corrosion potential (−0.82 V) and strongest electron transfer ability, was up to 8.5 times higher than that of AZVI. Correlation analysis revealed that the water contact angle (r= 0.87), free corrosion potential (r= −0.92), and surface Fe(II) proportion (r= 0.98) of the SAZVI samples played crucial roles in Cr(VI) removal. Furthermore, the enhanced elimination ability of SAZVI-Na2S was analyzed, primarily attributed to the adsorption of Cr(VI) by the FeSxshell, followed by the rapid release of internal electrons to reduce Cr(VI) to Cr(III). This process ultimately led to the precipitation of FeCr2O4and Cr2S3on the surface of SAZVI-Na2S, resulting in their removal from the water. This study provides insights into the influence of sulfur precursors on the reactivity of SAZVI and offers a new strategy for designing highly active AZVI for efficient Cr(VI) removal.

A concise total synthesis of the complex guanidinium toxin KB343 is reported traversing through an unusual sequence of chemoselective transformations and strategic skeletal reorganization. The absolute configuration is confirmed through an enantioselective route, and the structures of all key intermediates and the natural product itself are unassailably confirmed through X-ray crystallographic analysis.

Amorphous zero-valent iron (AZVI) has attracted wide attention due to its high-efficiency reduction ability. However, the effect of different EDA/Fe(II) molar ratios on the physicochemical properties of the synthesized AZVI requires further investigation. Herein, series of AZVI samples were prepared by changing the molar ratio of EDA/Fe(II) to 1/1 (AZVI@1), 2/1 (AZVI@2), 3/1 (AZVI@3), and 4/1 (AZVI@4). When the EDA/Fe(II) ratio increased from 0/1 to 3/1, the Fe0proportion on the AZVI surface increased from 26.0 to 35.2% and the reducing ability was enhanced. As for AZVI@4, the surface was severely oxidized to form a large amount of Fe3O4, and the Fe0content was only 74.0%. Moreover, the removal ability of Cr(VI) was in the order AZVI@3 > AZVI@2 > AZVI@1 > AZVI@4. The isothermal titration calorimetry results revealed that the increase of the molar ratio of EDA/Fe(II) would lead to the stronger complexation of EDA with Fe(II), which resulted in the gradual decrease of the yield of AZVI@1 to AZVI@4 and the gradual deterioration of water pollution after the synthesis. Therefore, based on the evaluation of all indicators, AZVI@2 was the optimal material, not only because its yield was as high as 88.7% and the secondary water pollution level was low, but most importantly, the removal efficiency of Cr(VI) by AZVI@2 was excellent. Furthermore, the actual Cr(VI) wastewater with the concentration of 14.80 mg/L was treated with AZVI@2, and the removal rate of 97.0% was achieved after only a 30 min reaction. This work clarified the effect of different ratios of EDA/Fe(II) on the physicochemical properties of AZVI, which provided insights for guiding the reasonable synthesis of AZVI and is also conducive to investigating the reaction mechanism of AZVI in Cr(VI) remediation.

This critical review describes a framework that can help to guide catalyst design in fundamental or practical aspects, illustrate reaction mechanism, optimize reactor functions, and operate system integration in catalytic LMC with a new point of view.

Volatile organic amines are a category of typical volatile organic compounds (VOCs) extensively presented in industrial exhausts causing serious harm to the atmospheric environment and human health. Monometallic Pd and Cu-based catalysts are commonly adopted for catalytic destruction of hazardous organic amines, but their applications are greatly limited by the inevitable production of toxic amide and NOxbyproducts and inferior low-temperature activity. Here, a CuO/Pd@SiO2core–shell-structured catalyst with diverse functionalized active sites was creatively developed, which realized the total decomposition of n-butylamine at 260 °C with a CO2yield and N2selectivity reaching up to 100% and 98.3%, respectively (obviously better than those of Pd@SiO2and CuO/SiO2), owing to the synergy of isolated Pd and Cu sites in independent mineralization of n-butylamine and generation of N2, respectively. The formation of amide and short-chain aliphatic hydrocarbon intermediates via C–C bond cleavage tended to occur over Pd sites, while the C–N bond was prone to breakage over Cu sites, generating NH2· species and long free-N chain intermediates at low temperatures, avoiding the production of hazardous amide and NOx. The SiO2channel collapse and H+site production resulted in the formation of N2O via suppressing NH2· diffusion. This work provides critical guidance for a rational fabrication of catalysts with high activity and N2selectivity for environmentally friendly destruction of nitrogen-containing VOCs.

The evaluation of the poisoning effect of complex components in practical gas on DCM (dichloromethane) catalytic ozonation is of great significance for enhancing the technique’s environmental flexibility. Herein, Ca, Pb, As, and NO/SO2were selected as a typical alkaline-earth metal, heavy metal, metalloid, and acid gas, respectively, to evaluate their interferences on catalytic behaviors and surface properties of an optimized urchin-like CuMn catalyst. Ca/Pb loading weakens the formation of oxygen vacancies, oxygen mobility, and acidity due to the fusion of Mn–Ca/Pb–O, leading to their inferior catalytic performance with poor CO2selectivity and mineralization rate. Noticeably, the presence of As induces excessively strong acidity, facilitating the inevitable formation of byproducts. Catalytic co-ozonation of NO/DCM is achieved with stoichiometric ozone addition. Unfortunately, SO2introduction brings irreversible deactivation due to strong competition adsorption and the loss of active sites. Unexpectedly, Ca loading protects active sites from an attack by SO2. The formation of unstable sulfites and the released Mn–O structure offset the negative effect from SO2. Overall, the catalytic ozonation of DCM exhibits a distinctive priority in the antipoisoning of metals with the maintenance of DCM conversion. The construction of more stable acid sites should be the future direction of catalyst design; otherwise, catalytic ozonation should be arranged together with post heavy metal capture and a deacidification system.

The oxidative potential (OP) of ambient particulate matter (PM) is a common metric for estimating PM toxicity and linking PM exposure to adverse health effects. Organic aerosol (OA), a dominant fraction of ambient PM worldwide, may significantly contribute to PM toxicity. Here, we investigated the source‐based OA components contributing to the OP of PM in the urban (Beijing, summer and winter) and rural (Gucheng, winter) environments of the North China Plain (NCP). Various OA components as identified by the aerosol mass spectrometer/aerosol chemical speciation monitor (AMS/ACSM), transition metals, and black carbon were compared with the OP of PM measured by dithiothreitol assays. The results consistently demonstrate the importance of OA as a contributor to PM's OP in both urban and rural NCP environments. Higher intrinsic OP was observed in winter Beijing than in summer, possibly due to OA being predominantly from anthropogenic sources in winter. Furthermore, different OA components were found to drive the response of OP in the two environments. More‐oxidized oxygenated OA (MO‐OOA), cooking OA, and oxidized primary OA (during winter) are the OA contributors to OP in the urban environment, with a dominant contribution from MO‐OOA. In contrast, biomass burning OA (BBOA) and OOA play a major role in the OP in the rural environment, with BBOA making the largest contribution. Overall, this work highlights the significance of OA in determining PM's OP and calls for more work to reveal the sources and characteristics of OA components contributing to OP across different regions. Ambient fine particulate matter (PM2.5) is a top risk factor for human health. The oxidative potential (OP) of PM2.5is widely used to estimate PM2.5toxicity and link PM2.5exposure with its adverse health effects. Organic aerosol (OA) constitutes a major fraction of PM2.5and can contribute substantially to the OP of PM2.5. But OA is also a complex mixture comprised of thousands of compounds each with widely different health effects. Here, we reveal the key OA components driving the OP in the urban and rural environments of the NCP. We find that more‐oxidized oxygenated OA, which is highly oxidized and can be formed from multiple atmospheric processes, is a dominant contributor to the OP in the urban environment. In contrast, biomass burning OA makes the largest contribution to the OP in the rural environment. In sum, different OA components are found to be the main drivers of the OP in the two environments. More studies are warranted to further our understanding of the causes, sources, and characteristics of the PM2.5OP over a wide range of geographical regions. Seasonal and spatial variations of oxidative potential (OP) of ambient particulate matter are foundOrganic aerosol (OA) is an important contributor to the oxidative potential in both urban and rural environmentsMore‐oxidized oxygenated OA and biomass burning OA have a dominant contribution to the OP in urban and rural environments, respectively Seasonal and spatial variations of oxidative potential (OP) of ambient particulate matter are found Organic aerosol (OA) is an important contributor to the oxidative potential in both urban and rural environments More‐oxidized oxygenated OA and biomass burning OA have a dominant contribution to the OP in urban and rural environments, respectively

Simultaneously elimination of NO and CO in the sintering flue gas is an urgent problem, in which the application of the bifunctional MnOxcatalyst has demonstrated its effectiveness in removing NO and CO simultaneously. Potassium salts are frequently found in the sintering flue gas and exert a detrimental influence on the catalytic performance of catalysts. Herein, the primary focus of this study is to investigate different K+species (K2SO4, KCl, KNO3) poisoning effect on bifunctional MnOx. The findings suggested a deactivation order in the sequence of KNO3> KCl > K2SO4. Fresh Mn-AC catalyst had finer grains, and poisoning elements were evenly distributed. XPS results revealed an obvious decrease in Mn4+and Oβspecies across all catalysts after K+species poisoning, hindering redox cycle activation and oxygen species mobility, thus impacting catalytic activity. The in situDRIFTS results indicated the forbidden of E-R route over KNO3-poisoned catalysts and low reactivity of adsorbed species after poisoning for NO removal. KNO3severely suppressed surface reaction paths on Mn-AC catalyst and declined the catalytic efficiency, especially in CO activation. Finally, a possible reaction mechanism model for the simultaneous removal of NO and CO was proposed. This study could provide reference for the development of bifunctional catalyst with high resistance to potassium salts.

The first enantioselective decarboxylative Negishi-type alkylations of α-oxy carboxylic acids are reported via the intermediacy of redox-active esters (RAEs). This transformation enables a radical-based retrosynthesis of seemingly trivial enantiopure dialkyl carbinols. This article includes a discussion of the history of such couplings, the retrosynthetic ramifications of such a coupling, the development of general conditions, and an extensive series of applications that vividly demonstrate how it can simplify synthesis.

Developing economic and applicable catalysts with elegant chlorine resistance and organic byproduct inhibition capability is of great significance for chlorinated volatile organic compounds (Cl-VOCs) eco-friendly purification. Here, ternary CexSr1–xTiO3catalysts with tunable surface acidity and oxygen species mobility were creatively fabricated using the hollow tubular-structured fruit hair of Platanus (FHP; a widespread greenery waste) as the scaffolding biotemplate. It is shown that the oxygen vacancy (Ov) triggered by the presence of Ce can optimize the synergy between the Lewis acid sites (LAS) and Brønsted acid sites (BAS). High concentration of Ovand BAS promotes the C–Cl cleavage of chlorobenzene (CB) and accelerates the desorption of Cl•radicals as inorganic chlorine. Simultaneously, the strong electron transfer within Ti-Ce-Sr linkage increases the acidity of LAS, resulting in the superior reducibility of Ce0.4Sr0.6TiO3and facilitating the deep oxidation of dechlorination intermediates. Additionally, the spatial confinement of the tubular structure remarkably accelerates the CB flow rate and reduces the residence time of byproducts over the prepared catalysts. Owing to these, CB can be efficiently destructed over Ce0.4Sr0.6TiO3with selectivity of CO2and inorganic chlorine dramatically enhanced, respectively, approximately 16 and 21 times at 275 °C compared to those of pure SrTiO3. The present work provides a feasible and promising strategy for engineering efficient catalysts for heterogeneous thermocatalytic reactions for industrial-scale Cl-CVOC destruction.

The catalytic oxidation of volatile organic compounds (VOCs) is of considerable significance for the sustainable development of the chemical industry; thus, considerable efforts have been devoted to the exploration of efficient catalysts for use in this reaction. In this regard, the development and utilization of single-atom catalysts (SACs) in VOCs decomposition is a rapidly expanding research area. SACs can be employed as potential catalysts for oxidizing VOC molecules due to their optimal utilization efficiency, unique atomic bonding structures, and unsaturated orbits. Progress has been achieved, while the challenges surrounding precise regulation of the microstructures of SACs for improving their low-temperature efficiency, stability, and product selectivity under practical conditions are remaining. Therefore, elucidating structure-performance relationships and establishing intrinsic modulating mechanisms are urgently required for guiding researchers on how to synthesize effective and stable functional SACs proactively. Herein, recent advances in the design and synthesis of functional SACs for application in the catalytic oxidation of VOCs are summarized. The experimental and theoretical studies revealing higher efficiency, stability, and selectivity of as-prepared functional SACs are being highlighted. Accordingly, the future perspectives in terms of promising catalysts with multi-sized composite active sites and the illustration of intrinsic mechanism are proposed. The rapid intelligent screening of applicable SACs and their industrial applications are also discussed.

Achieving excellent efficiency to mineralize volatile organic compounds (VOCs) under nonthermal plasma catalysis (NTP-catalysis) systems tremendously relies on the catalyst design. Herein, we report a dual-template strategy for synthesizing a core–shell structured nitrogen-enriched hollow hybrid carbon (N-HHC) by a facile pyrolysis of a Mn-ZIF-8@polydopamine core–shell precursor. N-HHC exhibits a remarkable plasma synergy effect and superior degradation efficiency for toluene (up to 90% with a specific input energy of 281 J/L), excellent CO2selectivity (>45%), and byproduct-inhibiting capability. Such outstanding functionality of the developed N-HHC is uniquely attributed to its hollow multistage and channeling structure, high concentration of O3-decomposing species (pyrrolic and oxide pyridinic-N), and abundant ZnO active sites. Shedding light on an efficient synthetic strategy for designing an advanced nanocatalyst with enhanced VOC destruction in the NTP-catalysis system, the present results could be extended to design other N-doped metal/metal oxide-decorated hollow porous carbons for environment-related applications.

The site-specific oxidation of strong C(sp3)–H bonds is of uncontested utility in organic synthesis. From simplifying access to metabolites and late-stage diversification of lead compounds to truncating retrosynthetic plans, there is a growing need for new reagents and methods for achieving such a transformation in both academic and industrial circles. One main drawback of current chemical reagents is the lack of diversity with regard to structure and reactivity that prevents a combinatorial approach for rapid screening to be employed. In that regard, directed evolution still holds the greatest promise for achieving complex C–H oxidations in a variety of complex settings. Herein we present a rationally designed platform that provides a step toward this challenge using N-ammonium ylides as electrochemically driven oxidants for site-specific, chemoselective C(sp3)–H oxidation. By taking a first-principles approach guided by computation, these new mediators were identified and rapidly expanded into a library using ubiquitous building blocks and trivial synthesis techniques. The ylide-based approach to C–H oxidation exhibits tunable selectivity that is often exclusive to this class of oxidants and can be applied to real-world problems in the agricultural and pharmaceutical sectors.

Catalytic conversion of NO to NO2stands as a pivotal step governing NOxpurification technology, with its effectiveness relying heavily on the utilization of high-performance catalysts. Herein, we harness a facile ligand-assisted self-assembly strategy to fabricate mesoporous Co3O4with abundant oxygen vacancies (M-Co3O4), aiming at improving the activity of NO oxidation. For comparison, Co3O4nanoflakes (F-Co3O4) and bulk Co3O4(B-Co3O4) were synthesized from a hydrothermal method and direct calcination of cobalt nitrate, respectively. Activity results reveal that M-Co3O4can oxidize 88% of NO at 275 °C under a GHSV of 180,000 h–1, surpassing both F-Co3O4(70% at 325 °C) and B-Co3O4(66% at 325 °C). Extensive characterizations indicate that the exceptional activities of M-Co3O4are predominantly attributed to the synergistic effects of its surface Co2+species, weak Co–O bond strength, and high mobility of surface lattice oxygen. This work lays the groundwork for the advancement of high-performance Co3O4-based catalysts for atmospheric contaminants remediation.

Light alkanes (LAs), typical VOCs existing in both stationary and mobile sources, pose significant environmental concerns. Although noble metal catalysts demonstrate strong C–H bond activation, their effectiveness in degrading LAs is hindered by inherent challenges, including poor chemical stability and water resistance. Here, from a new perspective, we propose a feasible strategy that adjusting the metal bond lengths within Pd clusters through partial substitution of smaller radius 3d transition metals (3dTMs) to prioritize the activation of low-energy C–C bonds within LAs. Benefiting from this, PdCo/CeO2exhibits exceptional catalytic performance in propane degradation due to their high capacity for C–C cleavage stemming from the shorter Pd–Co length (2.51 Å) and lower coordination number (1.73), boosting the activation of α-H and β-H of propane simultaneously and accelerating the mobility of postactivated oxygen species to prevent Pd center deep oxidation. The presence of 3dTMs on Pd clusters improves the redox and charge transfer ability of catalysts, resulting in an amplified generation of oxygen vacancies and facilitating the adsorption and activation of reactants. Mechanistic studies and DFT calculations suggest that the substitution of 3dTMs significantly accelerate C–C bond cleavage within C3 intermediates to generate the subsequent C2 and C1 intermediates, suppressing the generation of harmful byproducts.

Non-vanadium-based catalysts with high SO2tolerance are still interesting in selective catalytic reduction of NO by NH3(NH3-SCR) and SO2adsorption is the foremost step for the deactivation of catalysts. In order to alleviate the adsorption of SO2, we fabricated a series of rhenium (Re; without stable sulfate) supported TiO2catalysts and studied their SO2tolerance for the first time. Owing to suitable surface acidity and reducibility, ReOx/TiO2catalysts exhibited satisfactory activity in a wide temperature range of 250–350 °C. As expected, experimental results and DFT calculations indicated that SO2adsorption on ReOx/TiO2catalysts was rather weak, thus the catalysts performed excellent SO2tolerance in the NH3-SCR reaction. Moreover, in situDRIFTS indicated that the NH3-SCR reaction on ReOx/TiO2catalysts followed the Eley–Rideal mechanism and SO2had little effect on the reaction mechanism. Our findings should provide new insights into the development of SCR catalysts with high SO2tolerance.

It is of great significance to design highly active and stable catalysts for CO oxidation. Herein, a Pt/In–SnO2catalyst was firstly fabricated viaa facile hydrothermal reaction coupled with photoreduction strategy, achieving 1 vol% of CO totally oxidized at just 145 °C, over 200 °C lower than that of Pt/SnO2. Moreover, Pt/In–SnO2demonstrates superior catalytic stability and recyclability under both dry and humid conditions. Incorporation of In cations results in marked structure distortion of SnO2, promoting the formation of oxygen vacancies and enhancing the concentration and mobility of reactive oxygen species. Abundant Pt sites over Pt/In–SnO2further accelerate CO adsorption and activation. Density functional theory results prove that the energy barrier of CO oxidation reduces from 0.85 to 0.75 eV after In doping and the produced CO2can desorb spontaneously from the catalyst surface, which accelerates the CO oxidation process. This work provides new ideas for designing robust catalysts for low-temperature CO elimination.

Optimizing the interaction between metal active centers and supports by tuning crystal facets is an effective strategy to improve the activity and stability of catalysts. Herein, α-MnO2nanowires with different exposed crystal facets (respectively (310), (110) and (100)) were synthesized viaa facile hydrothermal method to promote the activity of an Au/α-MnO2catalyst for propane combustion. Results reveal that Au/α-MnO2-110 exhibits the highest catalytic activity, achieving 90% propane (2500 ppm) conversion at just 216 °C (apparent activation energy as low as 50.2 kJ mol−1). Compared with Au/α-MnO2-310 and Au/α-MnO2-100, Au/α-MnO2-110 with the largest quantity of oxygen vacancies, strong reducibility, and high surface oxygen mobility possesses the best capability for adsorbing and activating oxygen molecules. DFT results reveal that the (110) facet of α-MnO2has the lowest formation energy of oxygen vacancies (Evo(110) = 0.6 eV), suggesting the presence of weak surface Mn–O bonds, facilitating the formation of Auδ+species and therefore promoting C–H bond breaking in propane. This work highlights a new strategy for the design of efficient catalysts for stable light alkane low-temperature decomposition by surface exposed facet engineering.

Iron vanadate (FeVO4) nanorods are used as a carrier to support manganese (Mn) and cerium (Ce) oxides for the selective catalytic reduction (SCR) of nitrogen oxides (NOx) with NH3for the first time. Among these developed Ce–Mn/FeVO4catalysts with different molar ratios of Ce/Mn, the Ce0.2Mn0.2/FeVO4catalyst exhibits the best de-NOxperformance and N2selectivity, which are higher than 90% in a wide temperature window of 90–420 °C. Through a series of characterization techniques, it is found that the synergistic effect between Ce and Mn enhances the reduction ability and the number of acid sites on the catalyst, which facilitates the adsorption and conversion of flue gas. The introduction of an appropriate ratio of Ce/Mn increases the concentration of Mn4+and chemisorbed oxygen (OS) on the catalyst, leading to a “fast SCR reaction” with oxidizing NO to NO2, which significantly improves the low-temperature de-NOxefficiency. In addition, the interaction between the active components (Ce/Mn) and the support (FeVO4) increases the de-NOxperformance of Ce0.2Mn0.2/FeVO4at high temperatures. In the meantime, the Mn4++ Ce3+↔ Mn3++ Ce4+reduction electron pair formed between Ce and Mn promotes the transport of electrons, which is also beneficial for the SCR reaction at low temperature. The in situdiffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) reveals that the SCR reaction over Ce0.2Mn0.2/FeVO4catalyst follows both Eley–Rideal (E–R) and Langmuir–Hinshelwood (L–H) reaction mechanisms.

An operationally simple method to employ nonactivated carboxylic acids as alkylating agents in the N-alkylation of heterocycles is reported through an electrochemically driven anodic decarboxylative process. A wide substrate scope across a range of heterocycles is demonstrated along with a series of applications that significantly reduce the step count required to access such medicinally relevant structures.

The intriguing structure of tagetitoxin (1), a long-standing challenge in natural product synthesis, has been the subject of multiple revisions and has been confirmed through total synthesis. The route commences from a renewable furan starting material and features a number of unusual transformations (such as rearrangements, bromocyclization, and P(V)-based phosphate installation) to arrive at the target in 15 steps. As the route was designed to enable access to both enantiomers, the absolute configuration of the natural product could be assigned using a bioassay on (+)-1and (-)-1.

An asymmetric approach for the first total synthesis of (−)-rhodomollanol A, a highly oxidized diterpenoid, is described. The efficient synthetic strategy features three key transformations: (1) an oxidative dearomatization-induced (5 + 2) cycloaddition/pinacol-type 1,2-acyl migration cascade to build up the bicyclo[3.2.1]octane skeleton; (2) a retro-Dieckmann fragmentation/vinylogous Dieckmann cyclization cascade to assemble the bicyclo[3.3.0]octane subunit; and (3) a photo-Nazarov cyclization/intramolecular cycloetherification cascade to forge the 7-oxabicyclo[4.2.1]nonane core structure of the natural product.

The development of noble metal free and highly active cocatalysts is critically important and also challenging for the practical applications of photocatalytic hydrogen production. Here, ultrafine MoO2cocatalyst nanoparticles (≤10 nm) were in situsolvothermally synthesized on carbon nitride nanosheets (CNSs). We found that the ultrafine MoO2nanoparticle decorated CNS exhibits higher electrocatalytic hydrogen evolution reaction (HER) performance than Pt–CNS. Besides, CNS with a curly thin nanosheet structure has an increased specific surface area and broadened bandgap after the solvothermal process compared to bulk carbon nitride (CN). Characterization results reveal that the strong interfacial interaction between metallic MoO2and CNS greatly promotes the photogenerated electrons extracted from CNS to MoO2, resulting in efficient electron excitation and charge transfer in the composite. Accordingly, the hydrogen production rate of 1.0 wt% MoO2/CNS is 3.4 and 1.6 times higher than that of the same mass noble-metal Pt loaded CN and CNS under visible light irradiation, respectively. This work may provide a guide for constructing non-noble metal cocatalyst modified materials for efficient photocatalytic hydrogen production.

Nitric oxide (NO) emitted from the combustion of fossil fuels has drawn global concern, and the oxidation of NO contributes greatly to the DeNOxprocess. Herein, single-crystal γ-MnO2catalysts with well-defined hollow-sphere-, sea-urchin-, and flower-like morphologies (γ-MnO2-HS, γ-MnO2-SU, and γ-MnO2-F) were rationally designed and synthesized viaan environmental-friendly template-free hydrothermal strategy. The physicochemical properties of the prepared materials were characterized by XRD, FE-SEM, TEM, BET, XPS, H2-TPR, O2/NO-TPD and in situDRIFTS, and their catalytic activities in NO oxidation were evaluated. The results showed the γ-MnO2-HS sample possessed the highest activity and could oxidize 91.1% of NO at 275 °C, which was obviously higher than those of the γ-MnO2-SU and γ-MnO2-F catalysts. It was found that the presence of abundant surface-adsorbed oxygen and the largest quantity of Mn3+over the γ-MnO2-HS material respectively accelerated the processes of NO adsorption and O2activation, which greatly promoted the NO oxidation process. This work provides significant insights into NO oxidation over γ-MnO2catalysts.

The alkali metal potassium has the functions of structure promotion and electronic modulation in metal oxides. Herein, diverse potassium precursors (KOH, KNO3, K2SO4, and KCl) were introduced to α-MnO2nanorods through a facile post-processing strategy. The presence of potassium species has a remarkable promotion effect on the catalytic performance of α-MnO2. Amongst them, the KOH/MnO2sample has the highest activity and can destroy 90% toluene (1000 ppm) at just 226 °C with a reaction rate of 3.39 × 10−4mol gcat−1s−1, which is over 20 times higher than that of pure α-MnO2. Different anions in the potassium precursors bring a distinct mutation in the α-MnO2structure, promote the formation of MnO6–K–MnO6bridging bonds in α-MnO2, and exhibit obvious diverse abilities for balancing charge transfer. KOH is identified as the most promising precursor for alkali metal modification, which significantly improves the distribution of K species over the α-MnO2surface and strengthens the content and activity of lattice oxygen. It is confirmed that the lattice oxygen plays a key role in the catalytic oxidation of toluene over α-MnO2, which follows the Mars–van Krevelen mechanism. Positive hole defects (Mn3+) caused by KOH treatment play an important role in the diffusion of O and enhance the reducibility of manganese oxide. In addition, the enhanced specific surface area, pore volume, and surface acidity are also conducive for the catalytic oxidation of toluene.

The degradation of volatile organic compounds (VOCs) with simultaneous removal of the secondary pollutant NOxis a promising solution for catalytic elimination of nitrogen-containing VOCs (NVOCs). Herein, a series of mixed CuxMg3–xAlO oxides were prepared and tested for selective catalytic oxidation of n-butylamine. The Cu content of the catalysts significantly impacted their performance. Cu0.4Mg2.6AlO exhibited the best catalytic activity, with 100% conversion of n-butylamine and 83% N2selectivity at 350 °C. The catalysts were characterized by NH3-TPD, XPS, EPR, UV–vis, and H2-TPR to reveal the structure–activity relationship. On the basis of DRIFTS results, the reaction mechanism of selective oxidation of n-butylamine was proposed. Additionally, selective catalytic reduction of NO with NH3was further tested using Cu0.4Mg2.6AlO to remove NOx, which was generated after the selective oxidation process. By coupling selective catalytic oxidation of NVOCs with selective catalytic reduction of NOx, it provides a new effective strategy to synergistically remove NVOCs and NOx.

Pt/Eu2O3-CeO2materials with different Eu concentrations were prepared and applied to toluene destruction, and the remarkable promotion impact of EuOxon Pt/CeO2can be observed. The characterization results reveal that the presence of EuOxsignificantly enhances the redox property, lattice O concentration, and Ce3+ratio of the Pt/CeO2material, which facilitates the dispersion and activity of Pt active sites and thus accelerates the decomposition process of toluene. Among all catalysts, a sample with an Eu content of 2.5 at.% (Pt/EC-2.5) possesses the best catalytic activity with 0.09 vol% of toluene completely destructed at 200 °C under a relatively high GHSV of 50000 h−1. The possible reaction pathway and mechanism of toluene combustion over Pt/Eu2O3-CeO2samples are presented according to in-situDRIFTS, which confirms that the toluene oxidation process obeys the Mars-van Krevelen mechanism with aldehydes and ketones as primary organic intermediates.

Shape effects of nanocrystal catalysts in different reactions have attracted remarkable attention. In the present work, three types of α-Fe2O3oxides with different micromorphologies were rationally synthesized via a facile solvothermal method and adopted in deep oxidation of ethane. The physicochemical properties of prepared materials were characterized by XRD, N2sorption, FE-SEM, HR-TEM, FTIR, in situ DRIFTS, XPS, Mössbauer spectroscopy, in situ Raman, electron energy loss spectroscopy, and H2-TPR. Moreover, the formation energy of oxygen vacancy and surface electronic structure on various crystal faces of α-Fe2O3were explored by DFT calculations. It is shown that nanosphere-like α-Fe2O3exhibits much higher ethane destruction activity and reaction stability than nanocube-like α-Fe2O3and nanorod-like α-Fe2O3due to larger amounts of oxygen vacancies and lattice defects, which greatly enhance the concentration of reactive oxygen species, oxygen transfer speed, and material redox property. In addition to this, DFT results reveal that nanosphere-like α-Fe2O3has the lowest formation energy of oxygen vacancy on the (110) facet (Evo(110) = 1.97 eV) and the strongest adsorption energy for ethane (−0.26 eV) and O2(−1.58 eV), which can accelerate the ethane oxidation process. This study has deepened the understanding of the face-dependent activities of α-Fe2O3in alkane destruction.

In the present work, a series of MOF-74 (Ni) materials with narrow micropore channels and abundant unsaturated metal sites was respectively prepared via hydrothermal (HT), condensation reflux (CE), and microwave-assisted (MW) methods. The physicochemical properties of synthesized materials were characterized by powder X-ray diffraction, N2-sorption, field-emission scanning electron microscopy, Fourier-transform infrared (FTIR), thermogravimetric (TG)/TG-FTIR, X-ray photoelectron spectroscopy, UV–vis–near infrared, NH3/CO2-temperature programmed desorption, and in situdiffuse reflectance infrared Fourier transform spectroscopy. Their CO2/N2adsorption performances were evaluated by isotherm adsorption and dynamic adsorption experiments. We found that the MW is a rapid and facile protocol for the synthesis of MOF-74 (Ni) materials with highly efficient CO2capture capacity. The well-shaped MW-140 adsorbent with superior CO2adsorption capacity of 5.22 mmol/g at 25 °C can be obtained within 60 min by the MW process, almost 6 times higher than that of the commercial activated carbon (0.89 mmol/g). Results of dynamic adsorption experiments showed that the MW-140 material possesses the highest CO2adsorption capacity of 3.37 mmol/g under humid conditions (RH = 90%). Importantly, MW-140 has excellent adsorption stability and recyclability, superior CO2capture selectivity (CO2/N2= 31), and appropriate isosteric heat in CO2adsorption (21–38 kJ/mol), making it a promising and potential material for industrial CO2capture. Characterization results demonstrated that the high capture capability of MOF-74 (Ni) materials can be attributed to the synergistic effect of abundant narrow micropore channels and rich five-coordinated Ni2+open metal sites which are beneficial for the trapping of CO2molecules.

A simple total synthesis of herqulines B and C is reported, modeled on the reductive biosynthesis reported previously by other researchers. Commencing from tyrosine, these alkaloids were fashioned through a dimerization, macrocyclization, and four consecutive reductions. Emerging from these studies are strategic insights on the synthesis of these strained alkaloids, as well as mild conditions for the exhaustive reduction of diketopiperizines.

Manganese-based metal oxides are promising catalysts for the NH3-SCR (selective catalytic reduction) of NOxat low temperatures. However, manganese-based catalysts usually exhibit poor SO2and H2O tolerance. In order to overcome the fatal shortcoming, non-manganese-based CuyCe1−yW5Oxcatalysts (y= 0, 0.4, 0.5, 0.6, 1.0) are synthesized successfully by a standard co-precipitation method, and the catalytic performances of these catalysts are tested by the NH3-SCR of NOx. The results show that there are synergistic effects between Cu and Ce, which affect the CuyCe1−yW5Oxcatalysts in many aspects, such as the specific surface area, the surface contents of Ce3+and Cu2+, the reductive strength and the amount of weak and strong acid sites on the surface. Moreover, the synergistic effects also have an impact on the de-NOxmechanism of CuyCe1−yW5Oxcatalysts, and finally decide their catalytic performances. Among all the CuyCe1−yW5Oxcatalysts, the Cu0.5Ce0.5W5Oxcatalyst shows the best catalytic de-NOxperformance and good tolerance to SO2and H2O poisoning. This work may provide a suggestion for the design of non-manganese-based SCR catalysts with the desired de-NOxperformance and good SO2tolerance by making use of the synergistic effects between different metal oxides.

The contribution of long noncoding RNAs (lncRNAs) to pancreatic cancer progression and the regulatory mechanisms of their expression are attractive areas. In the present study, the overexpression of lncRNA-BX111887 (BX111) in pancreatic cancer tissues was detected by microarray and further validated in a cohort of pancreatic cancer tissues. We further demonstrated that knockdown or overexpression of BX111 dramatically repressed or enhanced proliferation and invasion of pancreatic cancer cells. Mechanically, BX111 activated transcription of ZEB1, a key regulator for epithelia-mesenchymal transition (EMT), via recruiting transcriptional factor Y-box protein (YB1) to its promoter region. Moreover, we revealed that BX111 transcription was induced by hypoxia-inducible factor (HIF-1α) in response to hypoxia. In addition, BX111 contributed to the hypoxia-induced EMT of pancreatic cells by regulating expression of ZEB1 and its downstream proteins E-cadherin and MMP2. Coincidence with in vitro results, BX111 depletion effectively inhibited growth and metastasis of xenograft tumor in vivo. The clinical samples of pancreatic cancer further confirmed a positive association between BX111 and ZEB1. Moreover, high BX111 expression was correlated with late TNM stage, lymphatic invasion and distant metastasis, as well as short overall survival time in patients. Taken together, our findings implicate a hypoxia-induced lncRNA contributes to metastasis and progression of pancreatic cancer, and suggest BX111 might be applied as a potential biomarker and therapeutic target for pancreatic cancer.

•The effect of SO2on activity of Zn-poisoned catalyst depends on Zn content.•Surface sulfate was formed on catalyst with low Zn content in the presence of SO2.•ZnSO4was formed on catalyst with high Zn content in the presence of SO2.•Surface sulfate could form new Brønsted acid sites and increase catalytic activity.

Migration and invasion inhibitory protein (MIIP) is recently identified as an inhibitor in tumor development. However, the regulatory mechanism and biological contributions of MIIP in pancreatic cancer (PC) have been not elucidated. In this study, we demonstrated a negative feedback of MIIP and hypoxia-induced factor-1α (HIF-1α), which was mediated by a hypoxia-induced microRNA. Compared with paracarcinoma tissues, MIIP was downregulated in PC tissues. Overexpression of MIIP significantly impeded the proliferation and invasion of PC cells both in vitro and in mouse xenograft models. We further verified MIIP was downregulated under hypoxia in a HIF-1α-mediated manner. Interestingly, although MIIP promoter containing two putative hypoxia response elements (HREs), the chromatin immunoprecipitation (ChIP) and luciferase reporter assays did not support an active interaction between HIF-1α and MIIP promoter. Meanwhile, microRNA array revealed a hypoxia-induced microRNA, miR-646, impaired stability of MIIP mRNA and consequently inhibited its expression by targeting the coding sequence (CDS). Coincidently, knockdown of miR-646 significantly repressed proliferation and invasion ability of PC cells both in vitro and in vivo by upregulating MIIP expression. Besides, ChIP and luciferase reporter assays further validated that HIF-1α activated transcription of miR-646 in hypoxia condition. Therefore, these results suggested HIF-1α indirectly regulated MIIP expression in post-transcriptional level through upregulating miR-646 transcription. Conversely, our results further revealed that MIIP suppressed deacetylase ability of histone deacetylase 6 (HDAC6) to promote the acetylation and degradation of HIF-1α, by which impairing HIF-1α accumulation. What is more, a specific relationship between downregulated MIIP and upregulated miR-646 expression was validated in PC samples. Moreover, the dysregulated miR-646 and MIIP expression was correlated with advanced tumor stage, lymphatic invasion, metastasis and shorter overall survival in PC patients. Together, our results highlight that the reciprocal loop of HIF-1α/miR-646/MIIP might be implemented as an applicable target for pancreatic cancer therapy.

The decomposition of tetrachlorobenzene (TeCB) emitted from simulated fly ash was studied in a low-temperature pyrolysis–catalysis coupled system. The influences of catalyst support, active component type, active phase-to-assistant ratio, vanadium loading, and catalyst calcination temperature on TeCB conversion were comprehensively investigated. The optimal catalyst composition and preparation conditions were determined through single-factor experiments. Moreover, the effects of reaction temperature, space velocity, and pollutant initial concentration on TeCB decomposition efficiency were explored by orthogonal experiments. The possible mechanism for PeCB decomposition over prepared V2O5–WO3/TiO2catalysts was proposed based on reaction-byproduct composition and distribution. It is found that the TeCB decomposition efficiency is positively correlated with reaction temperature while being negatively correlated with gas hourly space velocity (GHSV) and TeCB initial concentration. GHSV has the most significant effect on TeCB decomposition, followed by reaction temperature and TeCB concentration. Under optimal conditions of space velocity of 600 h–1, reaction temperature of 350 °C, and TeCB initial concentration of 0.5 volume percent, the TeCB conversion can reach up to 94.1%. The key substeps of TeCB decomposition are aromatic pollutant adsorption, nucleophilic substitution, and intermediate electrophilic substitution. The TeCB molecules were first adsorbed on catalyst surface and then decomposed into low-chlorination aromatics and aromatic and aliphatic hydrocarbons as phenolates, benzoquinone, aldehydes, and carboxylic acids.

Novel CuMCeOx(M = Y, Eu, Ho, and Sm) trimetal oxide catalysts with developed mesoporosity and an enhanced oxygen migration capability were fabricated by a reproducible self-precipitation approach for the first time. The incorporation of a rare-earth element (especially Y, Eu, and Ho) can increase the reducibility of, and mobility of surface adsorbed oxygen on, a CuCeOxcatalyst, which leads to a remarkable increase in catalytic activity in the oxidation of toluene. Among these catalysts, the CuHoCeOxcatalyst possesses the highest oxidation activity, with the complete mineralization of toluene at 220 °C at a relatively high GHSV of 50 000 h−1, which is ascribable to the synergetic effect of Ho and the CuCeOxframework, which creates abundant active oxygen vacancies over mixed oxides. Raman spectroscopy and density functional theory (DFT) studies reveal that Ho element is coordinated to two oxygen atoms and occupies the site of a Ce atom, which changes the π-bonding of Ce in the CuCeOxbinary oxide and thus leads to the weakening of Ce–O bonds and an enhanced oxygen storage capacity. A possible reaction pathway and a mechanism for the combustion of toluene over a CuHoCeOxsample are proposed by means of in situDRIFTS and DFT studies, which prove that the toluene oxidation process obeys the Mars–van Krevelen mechanism, with aldehydes and ketones as the primary organic intermediates, before decomposition to CO2and H2O.

Developing photocatalysts with efficient spatial charge separation and transfer as well as a high light-harvesting ability remains a key challenge. Here, we report a facile in situprocess to decorate ultrathin g-C3N4nanosheets (NSs) with a co-catalyst, Cu2MoS4, for photocatalytic water splitting. The as-obtained Cu2MoS4/g-C3N4exhibits a superior photocatalytic H2evolution rate of 2170.5 μmol h−1g−1under visible light irradiation, which is nearly 677 and 34 times higher than that of bulk g-C3N4and g-C3N4NSs, respectively, and far exceeds that of most g-C3N4catalysts modified with other sulphide co-catalysts reported in the literature, demonstrating that Cu2MoS4can serve as a promising non-noble metal co-catalyst to couple with g-C3N4for highly efficient photocatalysts. Structural characterization confirms the well-defined morphology of Cu2MoS4/g-C3N4in which Cu2MoS4hollow spheres are uniformly attached on the ultrathin g-C3N4NSs with numerous micropores and vacancies. The optical properties indicate that Cu2MoS4/g-C3N4possesses a superb visible light absorption ability. The photoluminescence spectra, photocurrent response, and electrochemical impedance spectra combine to prove the highly efficient separation and migration of photogenerated electrons and holes. All these factors synergistically enhance the photocatalytic activity of Cu2MoS4/g-C3N4for photocatalytic water splitting, providing new insights into the rational design of high-performance visible light-driven photocatalysts based on earth-abundant elements.

MnOxoxides with different morphologies (nanowire (MnOx-W), nanocube (MnOx-C), nanorod (MnOx-R), and nanosphere (MnOx-S)) and exposed facets were synthesized viaa solvothermal method. The catalytic performance of the synthesized MnOx materials for methyl ethyl ketone (MEK) destruction was investigated. Results show that the activity of MnOx-W with highly exposed {101} facets of Mn3O4is superior to that of MnOx-C, MnOx-R, and MnOx-S exposing {321} facets of Mn2O3, {110} facets of MnO2, and {101} and {112} facets of Mn3O4, respectively. MEK can be completely mineralized into CO2at 195 °C over MnOx-W under a relatively high gas hourly space velocity of 37 200 h−1, which is even better than some typical noble metal loaded catalysts. The lowest apparent activation energy of MnOx-W (27.7 kJ mol−1) for MEK destruction also confirms its excellent catalytic activity. Density functional theory (DFT) results reveal that the {101} facets of Mn3O4have the highest MEK adsorption energy (0.79 eV), which indicates that MEK molecules have a high affinity to adsorb onto the MnOx-W surface, promoting the oxidation process of MEK. In situDRIFTS and TPSR results indicate that the mineralization of MEK into CO2over MnOx-W goes through an oxidation route with diacetyl as the primary intermediate. We found that the highly exposed {101} active facets, abundant oxygen vacancies, and excellent low-temperature reducibility are responsible for the superior oxidation performance of MnOx-W. This finding may bring new insights into the designing of highly effective catalysts and has implications for a wide range of reactions not limited to MEK oxidation.

Non-thermal plasma catalysis with high efficiency, high by-product selectivity and superior carbon balance is one of the most promising technologies in the control of volatile organic compounds (VOCs). Non-thermal plasma catalysis can be subdivided into three types: continuous operation in plasma catalyst (CIPC) system, sequential operation in plasma catalyst (SIPC) system and post plasma catalyst (PPC) system. In this review, a comprehensive discussion on the synergistic mechanism of the CIPC, SIPC and PPC systems is provided. For CIPC, the introduction of catalysts changed the discharge behavior and generated new active species. Plasma discharge modified catalyst surfaces were summarized. The behavior and mechanism of catalyst adsorption and surface reactions within a plasma reactor and plasma oxidation in SIPC were discussed. For PPC, the performance of the plasma modified gas composition and temporarily activated catalysts were analyzed. In addition, the by-product inhibition by catalysts was also discussed. Moreover, the synergistic effects of the plasma and catalysts of the three systems on VOC destruction were critically reviewed. Based on these studies, the catalyst characteristics suitable for the CIPC, SIPC and PPC systems were summarized. Finally, the outlook on non-thermal plasma catalysis coupled systems in VOC control was proposed. It can be reasonably anticipated that this review is meaningful for deepening our understanding of the fundamental scientific principles regarding the catalytic oxidation of VOCs in non-thermal plasma catalysis systems, providing valuable and feasible references for researchers and designers on the efficient reduction and control of VOCs.

LaxSr2−xMnCoO6materials with different Sr contents were prepared by a coprecipitation method, with LaSrMnCoO6found to be the best catalyst for 1,2-dichloroethane (DCE) destruction (T90= 509 °C). As such, a series of LaSrMnCoO6/H-ZSM-5 composite materials were rationally synthesized to further improve the catalytic activity of LaSrMnCoO6. As expected, the introduction of H-ZSM-5 could remarkably enlarge the surface area, increase the number of Lewis acid sites, and enhance the mobility of the surface adsorbed oxygen species, which consequently improved the catalytic activity of LaSrMnCoO6. Among all the composite materials, 10 wt% LaSrMnCoO6/H-ZSM-5 possessed the highest catalytic activity, with 90% of 1,2-DCE destructed at 337 °C, which is a temperature reduction of more than 70 °C and 170 °C compared with that of H-ZSM-5 (T90= 411 °C) and LaSrMnCoO6(T90= 509 °C), respectively. Online product analysis revealed that CO2, CO, HCl, and Cl2were the primary products in the oxidation of 1,2-DCE, while several unfavorable reaction by-products, such as vinyl chloride, 1,1,2-trichloroethane, trichloroethylene, perchloroethylene, and acetaldehyde, were also formed viadechlorination and dehydrochlorination processes. Based on the above results, the reaction path and mechanism of 1,2-DCE decomposition are proposed.

A series of CuSO4/TiO2binary oxide catalysts with different CuSO4loadings (0–20 wt%) were prepared by a facile solid state impregnation protocol. The physicochemical properties of the catalysts and the NO reaction route were extensively characterized viaN2adsorption/desorption, XRD, Raman, NH3-TPD, NO-TPD, H2-TPR, XPS, and in situDRIFTS. The CuSO4content had significant influence on catalytic activity. High CuSO4loading favored the solid reaction between CuSO4and TiO2, promoted the formation of sulfite and weak acid sites, and obviously increased the activity at temperatures below 340 °C. However, at a temperature higher than 340 °C, NH3oxidation increased with CuSO4loading and caused NOxconversion to decrease when the CuSO4loading was higher than 10 wt%. Thus, the sample with 10 wt% CuSO4loading presented the broadest temperature window and it also showed an excellent resistant to SO2and H2O. Both Brønsted and Lewis acid sites were formed on the catalyst. S–OH of sulfate and sulfite were the main reason for formation of Brønsted acid sites. NH3-SCR reaction on CuSO4/TiO2followed the Eley–Rideal mechanism: NH3first adsorbed on Brønsted and Lewis acid sites as NH4+and NH3, then reacted with gaseous NO and O2to form N2and H2O.

Porous cryptomelane-type octahedral molecular sieve (OMS-2) with mixed Mn valence and abundant lattice oxygen species has attracted much attention in volatile organic compounds (VOC) catalytic elimination. However, complete conversion of arene over OMS-2 catalysts at relatively low temperature is still a challenge due to its limited crystal structure and inferior stability. Here, a series of PdCe/OMS-2 catalysts with different Pd/Ce molar ratios was fabricated by a facile impregnation method and the physicochemical properties of which were extensively characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), Brunauer–Emmett–Teller (BET) method, X-ray fluorescence (XRF), X-ray photoelectron spectroscopy (XPS), temperature programmed reduction of H2(H2-TPR), Raman, In situdiffused reflectance infrared Fourier transform spectra (DRIFTS), and density functional theory (DFT) calculations. Results show that the total conversion of toluene can be achieved at 207 °C over PdCe2 with apparent activation energy as low as 62.6 kJ/mol. The strong synergistic effect between Pd and Ce remarkably boosts the catalytic activity of OMS-2, attributed to the abundant Mn3+–O bands and active surface oxygen species. DFT results reveal that oxygen vacancy can be formed over PdCe2 much easily than that of Pd/OMS-2 and Ce/OMS-2 with the oxygen vacancy formation energy of 2.42, 2.83 and 2.68 eV, respectively. Simply increasing the Pd content cannot promote the catalytic activity although PdO is a critical active center in toluene oxidation. Oxygen vacancy attributed to the integrative effect of Pd, Ce and Mn species plays a prominent role over prepared catalysts in toluene activation process. The findings reported in this work showed new insights into the designing of highly efficient OMS-2 catalysts for VOC deep oxidation by tuning oxygen vacancy concentration.

Metal–organic frameworks (MOFs) containing two different inorganic metal nodes (known as bimetallic MOFs) could exhibit enhanced CO2adsorption compared to their monometallic counterparts. Herein, a series of bimetallic NiCo-MOF-74 synthesized by microwave-assisted method were investigated for CO2adsorption. It was revealed that narrow micropore channel with open metal site (OMS) of the bimetallic NiCo-MOF-74 influence CO2binding affinity and CO2/N2adsorption. The CO2uptake of Ni1Co1-MOF-74 at 0 °C and 1 bar (100 kPa) was 8.30 mmol g−1which is higher than those of Ni-MOF-74 (3.99 mmol g−1), Ni6Co1-MOF-74 (3.62 mmol g−1), Ni1Co6-MOF-74 (6.40 mmol g−1) and Co-MOF-74 (5.03 mmol g−1). While this could be related to the high specific surface area of Ni1Co1-MOF-74, Ni1CO2-MOF-74 with relatively low specific surface areas still shows good CO2adsorption capacity up to 5.70 mmol/g, which is higher than those of adsorbents Ni-MOF-74, Ni6Co1-MOF-74 and Co-MOF-74, indicating that adsorption performance mainly relies on coordinated metals. Ni1Co1-MOF-74 showed remarkable recyclability performance, ranking selectivity of CO2/N2reach up to 34, and suitable isosteric heat (31–23 kJ mol−1), manifesting a great probability for industrial CO2capture. As revealed, incorporated Ni2+/Co2+nodes within Ni1Co1-MOF-74, which are acting as active and open sites for CO2capture, led to the synergetic effects comprising of micropores as well as dense dual-metal sites.

Light alkanes make up a class of widespread volatile organic compounds (VOCs), bringing great environmental hazards and health concerns. However, the low-temperature catalytic destruction of light alkanes is still a great challenge to settle due to their high reaction inertness and weak polarity. Herein, a Co3O4sub-nanometer porous sheet (Co3O4-SPS) was fabricated and comprehensively compared with its bulk counterparts in the catalytic oxidation of C3H8. Results demonstrated that abundant low-coordinated Co atoms on the Co3O4-SPS surface boost the activation of adsorbed oxygen and enhance the catalytic activity. Moreover, Co3O4-SPS has better surface metal properties, which is beneficial to electron transfer between the catalyst surface and the reactant molecules, promoting the interaction between C3H8molecules and dissociated O atoms and facilitating the activation of C–H bonds. Due to these, Co3O4-SPS harvests a prominent performance for C3H8destruction, 100% of which decomposed at 165 °C (apparent activation energy of 49.4 kJ mol–1), much better than the bulk Co3O4(450 °C and 126.9 kJ mol–1) and typical noble metal catalysts. Moreover, Co3O4-SPS also has excellent thermal stability and water resistance. This study deepens the atomic-level insights into the catalytic capacity of Co3O4-SPS in light alkane purification and provides references for designing efficacious catalysts for thermocatalytic oxidation reactions.

The total syntheses of nine grayanane diterpenoids, namely, GTX-II (1), GTX-III (2), rhodojaponin III (3), GTX-XV (4), principinol D (5), iso-GTX-II (6), 1,5-seco-GTX-Δ1,10-ene (7), and leucothols B (8) and D (9), that belong to five distinct subtypes, were disclosed in a divergent manner. Among them, six members were accomplished for the first time. The concise synthetic approach features three key transformations: (1) an oxidative dearomatization-induced [5 + 2] cycloaddition/pinacol rearrangement cascade to assemble the bicyclo[3.2.1]octane carbon framework (CD rings); (2) a photosantonin rearrangement to build up the 5/7 bicycle (AB rings) of 1-epi-grayanoids; and (3) a Grob fragmentation/carbonyl–ene process to access four additional subtypes of grayanane skeletons. Density functional theory calculations were performed to elucidate the mechanistic origins of the crucial divergent transformation, which combined with late-stage synthetic findings provided insights into the biosynthetic relationships between these diverse skeletons.