The oscillatory baffled reactor (OBR) is one of the most promising reactor types for oxidative desulfurisation (ODS) due to high proven sulfur removal efficiency and improved mass and heat transport steps through the oxidation reaction. In Part III of this literature review, we review OBR design, scale-up, industrial application and economic considerations. Practical application of OBR for ODS process is described, catalytic systems are presented and the remaining challenges are outlined.

A multifunctional hierarchical metal-organic aerogel monolithic catalyst with secondary hollow-structure for the oxidation-condensation tandem reaction.

Responsive molecularly imprinted nanozyme with H2O2 self-supply cascade catalytic system for targeted enhancement of chemodynamic therapy.

Elucidating charge transfer and radical mechanisms in PMS-activated dot-on-plate Fe2O3/Bi12O17Cl2 heterojunctions for enhanced photocatalysis.

Sustainable catalytic system for base-free oxidation of 5-hydroxymethylfurfural to bioplastic monomers: effect of waste slaughterhouse blood-derived carbon quantum dots in nanocomposite catalysts.

Innovative integrated catalytic system for enhanced water treatment: Towards a safer future for drinking water

Air pollution remains a threat to human health and environment particularly in the places where traffic and industries are denser. Nano-catalysts have emerged as a promising prospect of enhancing the quality of air due to their high surface area and controllable reactivity alongside their capability to decompose pollutants at mild operating conditions. This review examines more recent advances in the field of nano-catalyst based air purification with specific focus on vehicle exhaust treatment. Photocatalytic nano materials have great potential for removing Nitrogen Oxides (NOx), Volatile Organic Compounds (VOCs) and particulate matter with the help of adsorption and oxidation mechanisms. These materials include TiO2, graphene, perovskites, metal oxides and metal-organic frameworks. They have also tested their performance in catalytic converters, diesel particulate filters and in photocatalytic coating that have been applied to transport infrastructures. This review will discuss the various categories of pollutants, limitations of traditional methods of air purification, nano-catalytic activity and as well as the updated advancements of nano-enabled filters. It also highlights the new technologies such as plasma-assisted photocatalysis, electrospun nanofibre filters and the graphene-enhanced filtration networks which are more durable and have higher degradation efficiency. Despite these materials showing good laboratory scale performance, there are still questions on their toxicity, environmental exposure, cost and long-term stability. This review also discusses these challenges along with future research interests that are focused on safer material designs and intelligent catalytic systems for vehicle emission control. In general, nano-catalysts offer cleaner air and more efficient purification of vehicle exhausts. These might support a shift towards healthier urban environments.

Herein, we report a one-pot dual oxyfunctionalization reaction of ubiquitous gem-dimethyl groups using a single Pd(II)/Pd(IV) catalytic system, achieving both hydroxyl-acyloxylation and diacetoxylation by employing N-pyridine ylide as a directing group. This strategy exhibits remarkable generality, tolerating a wide range of functional groups and enabling the late-stage modification of complex drug derivatives. Mechanistic studies, including 18O-labeling experiments, kinetic analysis, and DFT calculations, unveil a pathway involving sequential C-H activations. The observed heteroselectivity is governed by kinetic preferences, stemming from distinctive noncovalent interactions in key transition states. This work provides a novel solution to the intermolecular 1,3-heterodifunctionalization of C(sp3)-H bonds, offering a powerful and versatile toolkit for molecular construction.

Metal-catalyzed asymmetric C-H annulation enables enantioselective synthesis from simple precursors, but methods that simultaneously generate multiple stereogenic elements in a single step remain rare. We report the first Co(II)/Salox-catalyzed desymmetrizing atroposelective C-H annulation of phosphinic amides with ynamides, simultaneously generating a P-stereogenic center and C-C/C-N chiral axes in high yield and enantioselectivity (up to 87% yield, >99% ee). Notably, this catalytic system shows a substrate-dependent stereochemical outcome at the C-N axis, which is significant and nontrivial. DFT calculations are consistent with the experimentally observed stereochemical outcome and support a plausible model for stereocontrol. This work provides a valuable platform for the asymmetric synthesis of structurally and stereochemically complex organophosphorus compounds.

The global plastic waste crisis, especially from poly(ethylene terephthalate) (PET), demands urgent sustainable solutions. Using green hydrogen from renewable sources to hydrogenolyze PET shows promise for producing key industrial commodity chemicals including para-xylene (PX) and ethylene glycol (EG), which are essential for the production of polyester, antifreeze, and other chemicals. However, developing scalable, cost-effective, and atom-efficient processes for synthesizing drop-in chemicals via PET hydrogenolysis remains challenging. This study presents a catalytic system with a ternary Cu-Zr-Al inverse catalyst (Al-ZrO2/Cu) that operates at 180 °C and 6 MPa H2. It nearly quantitatively converts PET into PX (>99% yield) and EG (92% yield). The catalyst, with modulated surface acidity and abundant oxygen vacancies, selectively activates the benzylic C-O bonds in PET for efficient hydrogenolytic depolymerization. In hexafluoroisopropanol (HFIP)-mediated continuous-flow reactions, the process generates a spontaneously biphasic PX/EG mixture, simplifying separation. Mechanistic studies reveal that interfacial oxygen vacancies and Lewis acid centers synergistically activate H* species and macromolecular ester bonds. This work offers a strategic approach to interfacial catalyst design, providing a technically and economically feasible way to transform waste commodity plastics into high-demand bulk chemicals. By combining scalable catalysis with circular economy concepts, it enhances plastic waste valorization and delivers sustainable, large-scale solutions for global plastic pollution.

Ring‑opening copolymerization (ROCOP) of readily available monomers such as cyclic acetals and cyclic anhydrides offers an atom‑economical alternative strategy, yet efficient catalytic systems enabling precise control over chain sequence and molecular weight remain scarce. Herein, we report the use of the organic Meerwein‑type ion pair [Me3O]+[B(C6F5)4]- as a highly active, metal‑free catalyst for the cationic ROCOP of cyclic acetals with cyclic anhydrides. This method affords structurally diverse poly(ether‑ester)s with tunable AB/ABB‑type linkages (A=anhydride and B=formaldehyde). By varying polymerization time, temperature, and monomer feed ratio, the content of AB linkages could be precisely regulated from 58mol% to a fully alternating architecture, while Mn reached up to 70.4kDa. The scope of the methodology was extended to 3 cyclic acetals and 6 cyclic anhydrides, yielding a library of 14 well‑defined copolymers. This work provides a robust and versatile catalytic approach to sequence‑controlled, high Mn poly(ether‑ester)s, significantly enriching the synthetic toolbox for sustainable polymer materials.

The catalytic decomposition of ammonia under mild conditions is a promising route for green hydrogen production. However, conventional dissociative ammonia decomposition pathways over metal sites are suffering from the Brønsted-Evans-Polanyi (BEP) constraint which establishes an inverse correlation between atomic N binding energy and the N-H bond dissociation energy. Herein, we report a ruthenium-supported nitrogen-doped cerium oxide (Ru/N-CeO2) catalyst that breaks this limitation and exhibits significantly enhanced catalytic activity compared to its undoped counterpart. Furthermore, we reveal that N dopants can act as independent active sites, enabling an associative mechanism distinct from the conventional Ru-driven pathway. Comprehensive isotopic labelling experiments together with computational techniques elucidate the reaction mechanism over the N site and reveal a distinct correlation between the location of the active site and catalytic activity. The proximal N site exhibits the highest activity, challenging the conventional view that activity is dominated by metal-support interfacial sites. While N doping is a commonly used approach for surface modification, our findings show that it can also alter the reaction mechanism by introducing new active sites. These insights offer valuable guidance for the rational design of catalytic supports in ammonia decomposition and open new directions for catalytic systems limited by scaling relationships in heterogenous catalysis.

MgH2 is a promising hydrogen storage material due to its high capacity (7.6 wt %), low cost, and environmental benignity, but its application is hindered by sluggish kinetics and high thermodynamic stability. Constructing catalytic systems has proven effective in addressing these limitations. Herein, we report a two-dimensional NiTi-layered double hydroxide (NiTi-LDH) catalyst that achieves atomic-level dispersion of bimetallic Ni-Ti active sites. The MgH2-6 wt % NiTi-LDH composite exhibits significantly enhanced dehydrogenation performance, with the onset desorption temperature reduced from 290.1 °C (pristine MgH2) to 230.1 °C. The composite also demonstrates exceptional cycling stability, retaining 96.53% of its initial capacity after 100 cycles at 300 °C. Microstructural analysis reveals that NiTi-LDH nanosheets are uniformly dispersed in the MgH2 matrix, providing abundant bimetallic active sites. During cycling, in situ formation of Mg2Ni/Mg2NiH4 and Ti/TiHx species facilitates hydrogen diffusion and provides favorable nucleation sites for the reversible Mg/MgH2 phase transformation, collectively enhancing hydrogen storage kinetics and reversibility.

A cooperative CuCl/Brønsted acid catalytic system has been developed to enable divergent C3-functionalization of o-alkynylbenzaldehydes through a key O-5-exo-dig cyclization pathway. The resulting allylic carbocation intermediates can be efficiently intercepted by either styrenes or alcohols, affording 3-styryl-1-indenones and 3-alkoxy-1-indenones, respectively, with complete regioselectivity. The exocyclic styryl moiety serves as a synthetically versatile handle for late-stage diversification of indanocine-type scaffolds. This operationally simple method employs inexpensive CuCl as the sole metal catalyst under mild conditions, furnishing 35 examples in yields of up to 98%.

Water-induced structural dynamics of zeolite framework have been extensively explored in binary model systems comprising only water and zeolites. However, under practical zeolite catalytic systems, water coexists with organic guest molecules within the confined microporous environment, giving rise to dynamical and multicomponent host-guest interactions. Combining in situ spectroscopic characterization with theoretical calculations, this study unveils, at the molecular level, the dynamic ternary interplay among zeolite, confined aromatics, and water during SAPO-34-catalyzed methanol-to-olefins (MTO) reaction. The confined aromatics generated in situ spatially and electronically modify the zeolite framework, forming a molecular shield that protects the zeolite framework from hydrolytic attack. More importantly, water acts as a molecular scissor, continuously trimming the alkyl side-chains of confined aromatics, thereby retarding their polycyclic growth while promoting the efficient and sustained formation of light olefins. Across a series of eight-membered-ring (8-MR) zeolites (SAPO-34, SAPO-18, and SSZ-13), co-feeding water results in an orders-of-magnitude enhancement of catalyst lifetime while maintaining stable olefin production. The dynamic cooperative interplay among zeolite, confined aromatics, and water governs the framework stability and catalytic longevity during MTO conversion. This mechanistic insight extends the conceptual boundaries of zeolite host-guest chemistry and opens new avenues for harnessing the beneficial role of water in zeolite catalysis.

High-valent metal-oxo (HVMO) species generated from a homogeneous metal-ligand complex can provide high oxidation power to facilitate selective decontamination. However, sustaining a high reactivity of such a catalytic system is challenging due to the structural fragility of mononuclear-structured organic ligands that are susceptible to self-degradation. Moreover, because of the highly reactive and transient nature of the HVMO complex, its specific structural properties remain unclear, hindering the catalytic mechanism elucidation and system optimization. Here we propose the use of phenanthroline (phen) as a structurally robust alternative ligand for manganese ions (Mn2+) complexation and periodate (PI) activation, triggering the formation of a dinuclear Mn-oxo complex, [Mn2III,IV(μ-O)2(phen)4]3+. Impressively, this system achieved rapid sulfamethoxazole oxidation, exhibiting decontamination kinetics 2-5 orders of magnitude higher than those of conventional heterogeneous PI-based systems, and sustained high reactivity for a 10-h continuous operation via a resin-supported complex. Importantly, the structural-stable,diomand-core complex can be directly isolated from the reaction solution. Mechanical study revealed a unique dynamic "closed-open" structure of the Mn2III,IV(μ-O)2 complex for driving pollutant degradation. The system also demonstrated high efficiency and robustness for treating real waters. This study lays a fundamental framework to revolutionize HVMO-based advanced oxidation processes toward sustainable, robust water purification.

Abstract Based on the understanding of traditional catalysts, the dynamic evolution of the catalytic process has been deeply reviewed, leading to a new perspective of “ s mart catalytic site ”. It is worth noting that the similarity between the dynamic change of catalytic sites and the natural evolution law was revealed. The “ smartly catalytic coupling system ”, owing to the environmental intelligence-response feature, was innovatively proposed. Meanwhile, this paper points out that the absolute intelligent catalysis is absent; however, constructing an intelligent catalytic system may require the surface catalytic sites supported on a self-optimizing substrate, variable reaction conditions, and an AI-assisted advanced reaction platform. This dynamic smart catalytic system is expected to automatically and rapidly adjust to certain human demands, precisely and efficiently meeting the future development trends. Besides, completely understanding the inter-crossed relationship among the micro-catalytic site evolution process, natural species macro-adaptability, and the dialectic involving the dynamic unity of opposites principle, is significant for scientific researchers’ worldview development.

Understanding how vibrational energy is generated, redistributed, and dissipated at the nanoscale is central to contemporary molecular and chemical physics. Plasmonic nanostructures offer highly efficient channels for both driving and probing molecular vibrations, enabling access to regimes where steady-state populations markedly depart from thermal equilibrium. This perspective examines how anti-Stokes surface-enhanced Raman scattering (SERS) has become a quantitative tool for resolving such thermal and non-thermal vibrational populations within nanoscale hotspots. We first outline the general framework linking Stokes and anti-Stokes Raman/SERS intensities to vibrational occupation, followed by experimental approaches that realize and probe thermal excitation (nanoscale thermometry) and non-thermal excitation pathways. We conclude by highlighting key methodological challenges-especially plasmonic bias correction and quantitative population analysis-and discuss future opportunities for employing anti-Stokes SERS as a molecular-level probe of energy flow in next-generation nanophotonic and catalytic systems.

A composite catalytic system composed of choline chloride, p-chlorophenol, and zinc acetate was developed for the efficient glycolysis of waste polyethylene terephthalate (PET). Under optimal conditions (185°C, 4 h, 2.5 wt% catalyst), PET was depolymerized into high-purity bis(2-hydroxyethyl) terephthalate (BHET) with a yield of 96.3%. The catalyst structure was characterized by Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance. Key reaction parameters, such as temperature, ethylene glycol/PET ratio, and catalyst loading, were optimized. The obtained BHET was repolymerized by way of melt polycondensation to produce regenerated PET, which exhibited thermal and structural properties comparable with commercial PET, as confirmed by thermogravimetric analysis, differential scanning calorimetry, FTIR, and nuclear magnetic resonance. The catalyst demonstrated excellent reusability, maintaining over 82% BHET yield after six cycles. This study proposes a sustainable, highly efficient, and fully recyclable strategy for closed-loop PET recycling. Specifically, by harnessing a synergistic Lewis–Brønsted acid system, the strategy demonstrates outstanding scalability and thus holds considerable promise for near-term industrial application.

Abstract Asymmetric α-alkylation of ketones is a powerful synthetic tool; however, its application to challenging substrates, such as acyclic dialkyl ketones and unactivated alkyl electrophiles is limited. We describe a catalytic system employing a dinickel(I) complex that facilitates the enantioselective α-alkylation of acyclic dialkyl ketones using unactivated alkyl iodides. This method efficiently constructs ketones with quaternary carbon stereocenters in high yield while demonstrating outstanding levels of chemo-, regio-, and enantiocontrol.