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[Display omitted] • An effective strategy has been established by doping Ce into Cu NPs to tune the electronic state of Cu. • It attains the faradaic efficiency of C 2 H 4 as high as 53% with a current density of 150 mA/cm2. • Such performance is about 2.8-fold increase when compared with Cu NPs. • The electronic structure regulation and defective sites facilitate highly efficient C 2 H 4 production from CO 2 electroreduction. Coupling another metal element tends to produce catalytic controls of high activity and selectivity. However, this action is still poorly explored to improve the selectivity of the electroreduction of CO 2 to C 2 H 4 with high energy density. Herein, Ce-doped Cu nanoparticles (Ce-Cu NPs) are synthesized by one-step co-reduction method and presented a preferable example that promotes selective transformation of CO 2 to C 2 H 4 in a flow-cell configuration. Thereinto, high faradaic efficiency (FE) of C 2 H 4 for Ce-Cu-2 NPs could reach 53% with the current density of 150 mA cm−2, which is 2.8 times higher than that of Cu NPs. The outstanding performance mainly stems from tailoring the doped-Ce content shrinks particle sizes and forms oxygen defects due to the electron effect of nearby Ce atoms, boosting local electronic re-distribution of Cu. Meanwhile, in-situ Raman spectroscopies evidenced that the doping of Ce can enhance Cu site to bond *CO, which were beneficial to C–C coupling and thus endowed the catalyst with the superior catalytic performance in CO 2 electroreduction toward C 2 H 4. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu/Fe–N–C exhibits exceptional chloramphenicol catalytic activity and stability. • Chloramphenicol is efficiently degraded by free radicals and non-free radicals. • The adsorption of persulfate on Fe/Cu–N is more favorable than that on Fe–N sites. • Adjacent atom-dispersed Cu–N optimizes the Fe 3d orbital bonding distribution. Advanced oxidation processes (AOPs) are promising ways for oxidative degradation of organic pollutants. Atom-dispersed transition metal–nitrogen–carbon (M–N–C) materials exhibit excellent efficiency in activating peroxide bonds and have been extensively pursued for environmental remediation. However, M–N–C with single atoms suffer from intrinsic performance limit of complicated catalytic reactions due to structural simplicity and lack of synergistic active sites. Herein, derived from Fe/Cu–coordinated zeolitic imidazolate frameworks with molecular-scale cages, a well–designed catalyst featuring Fe–Cu dual–metal sites coordinated with N–doped carbon (Fe/Cu–N–C) was fabricated. Compared to the single-atom iron catalyst (Fe–N–C), Fe/Cu–N–C significantly enhanced the chloramphenicol removal rate from 0.073 to 0.093 min−1 due to the synergistic effects of Fe–Cu dual active site. Furthermore, Fe/Cu–N–C exhibits fantastic reactivity for peroxydisulfate (PDS) activation in a wide pH range (3.1 – 10.3). Density functional theory calculations revealed that Fe/Cu–N is the major active site, where electrons transfer from Cu to Fe ensure the low-valence state of Fe for catalytic oxidation. Besides, the optimization of adjacent Cu–N sites improves the bonding orbital distribution of Fe 3d orbitals and promotes the adsorption and cracking of PDS. These findings reveal the cooperative mechanism of Fe–Cu dual–atom site on PDS activation and develop a promising platform toward environmental purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanosheet MoS 2 exhibits high activity and excellent stability in RWGS reaction. • CO desorption is facilitated through electron transfer from Mo to O atoms. • Redox mechanism is involved in MoS 2 and MoS 2 /MoO 2. A nanosheet MoS 2 catalyst is prepared via the hydrothermal method and O incorporation by calcination strategy. The X-ray and BET characterizations show that the calcination results in a considerable increase in crystallinity and specific surface area (from 48.82 to 84.49 m2/g), leading to the efficient adsorption of CO 2. In situ DRIFTS spectra and DFT calculations reveal that redox mechanisms are involved in the RWGS reaction on MoS 2. CO desorption is facilitated by O incorporation through electron transfer from Mo to O atoms and the higher barriers of CO hydrogenation and dissociation. CH 4 formation is effectively suppressed by the edge sulfur vacancies through the weakened adsorption strength of CO. A remarkable CO 2 conversion (57 %) and high stability (>1000 h) are obtained at 600 °C. This performance is superior to those of traditional supported catalysts. This study reports a promising two-dimensional layered material for exploring excellent performance catalysts for the reverse water gas reaction. [ABSTRACT FROM AUTHOR]

It is a great challenge to develop a facile strategy to synthesize SACs with both high loading quantity and stability. Here, we report a silica-nanocasted method to not only prohibit structure collapsing of ceria supports during calcination process, but also facilitate the activation of oxygen species, consequently establishing strong metal-support interactions to stabilize and activate Pd single atoms. [Display omitted] • A facile strategy is devised to stabilize high-content Pd single-atom catalysts. • SiO 2 plays a vital role in stabilizing the structure against collapsing. • SiO 2 activates the surface oxygen by donating electrons to weaken Ce-O bond. • Strong metal-support interaction is achieved to stabilize and activate Pd atoms. • The promising catalytic activity and durability in CO oxidation can be achieved. In most cases, the sintering tendency of supported metal single atoms could be attributed to the unstable structural characteristics of supports in demanding operating conditions, particularly for high-loading single-atom catalysts (SACs), ultimately resulting in deactivation. To address this issue, SiO 2 is employed to enhance the structural stability of both supports and the supported Pd single atoms. SiO 2 serves not only to prevent the collapse of support structures but also to promote the activation of surface oxygen species by facilitating electron transfer with the supports. This, in turn, establishes strong metal-support interactions (MSIs) to stabilize and activate atomically dispersed Pd species. Additionally, the electrons donated from Ce-O and Si-O to Pd atoms further catalyze the formation of oxygen vacancies, ultimately leading to significantly improved activity and durability in CO oxidation. Without SiO 2 , the instability of support structure, coupled with the weak MSIs, promotes the aggregation of Pd atoms, resulting in relatively lower catalytic activity and durability. [ABSTRACT FROM AUTHOR]

[Display omitted] • BPO 4 with in-situ Brønsted acid sites was employed for glycerol dehydration. • BPO 4 shows high acrolein yield of 80 % and robust stability during 425 h test. • In-situ Brønsted acid site is highly selective for the secondary hydroxyl groups. • The construction of B[3] and P[4] defects is a prerequisite for the active site. Dehydroxylation of biomass-based platform molecules is critical for obtaining building blocks for use in the chemical industry. Acid catalytic dehydration has provided a feasible route. However, simultaneously pursuing high product-selective and ultra-stable catalysts for the dehydroxylation of polyols remains an open challenge. In this study, a strategy for in-situ Brønsted acid sites (BAS) with chemo-adsorption selectivity is proposed. The construction of defect sites B[3] and P[4] species has been proved to be a prerequisite for the dynamic acid site formation at hydrothermal conditions. The BPO 4 catalyst with in-situ BAS can achieve the high selectivity of acrolein (∼80%) and robust stability of catalyst (over 425 h) using glycerol dehydration as a model reaction. In addition, in-situ BAS is highly selective for secondary hydroxyl groups and has been extended to other substrate applications. This catalytic strategy provides a green, efficient, and economical approach for converting biomass-derived polyols to high-value-added chemicals. [ABSTRACT FROM AUTHOR]

[Display omitted] • A win–win strategy is established for recycling Li and preparing the catalyst. • Waste biomass and spent lithium-ion batteries are used to prepare inexpensive CoO-C catalysts. • CoO-C catalysts show a high turnover frequency value (2.9714 min−1). • The mechanism of catalytic degradation of ciprofloxacin is revealed. • Carbon coating reduces Co leaching rate and improves electron distribution. The functional utilization of transition metals from spent lithium-ion batteries (LIBs) is an essential upcycling way. Herein, we propose a win–win strategy to recover Li and prepare CoO-C catalysts from spent LIBs and waste biomass, and the CoO-C catalyst is used to activate peroxymonosulfate (PMS) to degrade ciprofloxacin (CIP). The interaction between CoO and carbon endows the CoO-C catalyst with a degradation efficiency of 99.99% within 30 min. Both the radical pathway (SO 4 · - and · OH) and the non-radical pathway (surface electron transfer) are involved in the degradation of CIP in the CoO-C/PMS system. The electrostatic potential indicates that the supported carbon improves the electron distribution, showing a particularly high turnover frequency (TOF) value (2.9714 min−1) for CIP. The efficient and stable degradation over a wide range of pH and different aqueous matrices indicates the potential application of CoO-C catalysts. Overall, the pyrolysis reduction upcycles spent LIBs and waste biomass, offering a green way to convert waste to value-added high-performance water remediation catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • This is the first report about DESs catalyst for one pot synthesis of glycidol. • The glycerol conversion for the KOH:MEA(1:2) catalyst reaches 98.6%. • The yield of glycidol for the KOH:MEA(1:2) catalyst reaches 80.2%. • The kinetics for synthesis of GD from GL and DMC catalyzed by DES was studied. A series of deep-eutectic solvents (DESs) with potassium hydroxide as hydrogen bonding acceptor and monoethanolamine (MEA) or polyethylene glycol (PEG) as hydrogen bonding donor were prepared and used as catalyst for the synthesis of glycidol and glycerol carbonate from glycerol and dimethyl carbonate. The effect of reaction parameter (reaction temperature, dimethyl carbonate/glycerol molar ratio, catalyst amount and reaction time) on the reaction was investigated in detail. It is found that the activity of KOH:MEA DES catalyst is related with its basicity. The KOH:MEA(1:2) exhibits higher catalytic activity, which may be due to the strong hydrogen bonding action between KOH:MEA(1:2) and reactants. The reaction kinetics model is also established and the reaction rate constant and active energy for each reaction are obtained by fitting the experimental data. The component concentration calculated by the kinetics model is close to the one of the experimental value. [ABSTRACT FROM AUTHOR]

Robust ZPOFs with multiple active sites are facilely constructed and show remarkable CO 2 adsorption and conversion performance under mild/green conditions. [Display omitted] • Novel ZPOFs with multiple active sites are prepared via ionothermal polymerization. • The ZPOFs show exciting dual-functions for CO 2 adsorption and conversion. • The ZPOF-mediated CO 2 coupling reaction can proceed under mild/green conditions. • The present ZPOF is easily separated and shows good stability and reusability. • The optimum catalyst exhibits excellent broad substrate scope. Porous organic frameworks fabricated by well-defined monomeric compounds with different active sites have been regarded as the promising nano-materials for improving the efficiency of CO 2 capture and utilization. In this study, novel zwitterionic porous organic frameworks (ZPOFs) alternately connected by benzimidazole, triazine and imidazolium modules were prepared facilely via ZnCl 2 -catalyzed bi-component polymerization. The influences of different monomer concentration and polymerization temperature on structural properties of the ZPOFs were discussed in detail. It indicates that the ZPOFs present attractive structure characteristics of high specific surface area and hierarchical pore structure, and have abundant hydrogen bond donors, Lewis bases and nucleophilic groups, respectively. The ZPOFs as-obtained were applied to CO 2 adsorption and conversion into cyclic carbonate by coupling with epoxide. The experiment results showed that the ZPOFs could afford the highest CO 2 adsorption capacity of 2505 μmol/g at 273 K and 1.0 bar CO 2 pressure. The effects of ZPOFs structures and reactions conditions on the catalytic performance were investigated. Under the optimized conditions of 70 °C, 2.0 MPa CO 2 for 2.0 h, and cooperating with tetrabutylammonium iodide (TBAI) cocatalyst, the ZPOF-450–30 could efficiently and selectively catalyze the CO 2 /epoxides cycloaddition reaction to yield corresponding cyclic carbonates. Moreover, the ZPOF-450–30 catalyst could be simply separated with durable high stability and activity. Finally, we compared the catalytic behaviors with reported similar heterogeneous catalysts and proposed a feasible ZPOFs-catalyzed mechanism. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly active SnMn composite was prepared for VOCs oxidation. • "Structure-performance" relationship was interpreted by multiple characterizations. • Reaction pathways were raised from an experimental angle. • O 3 decomposition and PM filtration by the SnMn composite were also tested. Catalytic oxidation is promising to eliminate VOCs. The challenge is to realize high efficiency under high space velocities and low oxidation temperatures. In this work, Sn-modified ɑ-MnO 2 was prepared via a facile redox protocol with varied Sn additions. The oxidation activity for 460 ppm benzene under 120 L/g/h space velocity reached a maximum level at a moderate Sn incorporation. The performance of this SnMn composite in terms of benzene conversion, CO 2 production, water and NO 2 resistance and cyclability was even better than those of commercial hopcalite catalyst. Easily accessible acid sites, abundant reactive oxygen vacancies and weakened Mn-O bonds were paramount to the diffusion of benzene molecules and transportation of surface oxygen, which were advantageous for the excellent benzene abatement. Finally, mechanic insights into the surface interaction between benzene and oxygen species were provided through comprehensive experimental investigations. The SnMn composite was also good at ozone decomposition and PM 2.5 filtration. [ABSTRACT FROM AUTHOR]