In this research, the Au nanoparticle was synthesized using a biosynthesized strategy by Mentha aquatic extract and characterized by Uv-vis spectroscopic method. The synthesized Au/NPs were used as a conductive mediator for the modification of the tramadol electrochemical sensor. The modified paste electrode with Au/NPs and 1-butyl-3-methylimidazolium tetrachloroborate (BMTCB) showed high catalytic

In this short review, we provide an account of a number of computational studies of catalytic reaction mechanisms carried out in our groups. We focus in particular on studies in which we came to realize during the course of the investigation that the active catalytic species was a bimetallic complex, rather a monometallic one as previously assumed. In some cases, this realization was in part prompted

A new type of catalyst for reactions via σ-bond activation is Rh(PAlP): Rh-Al heterobimetallic complex of diphosphine-based tridentate pincer-type PAlP ligand bearing an aluminyl moiety at the center coordination site. This work reports results of theoretical and computational studies of the unique Rh–Al direct bond, flexible behavior of Rh(PAlP) for substrate coordination, and new catalytic functions

Polyketide synthases (PKS) produce polyketides, a large group of secondary metabolites produced in bacteria, fungi, plants and certain animal families. PKSs have a huge potential to biosynthesize high-value active pharmaceuticals, agrochemicals, biofuels and industrial chemicals, among others. Additionally, they present ideal opportunities to engineer new polyketides, and the latter chemical novelty

In order to estimate the reactivity of a large number of potentially complex heterogeneous catalysts while searching for novel and more efficient materials, physical as well as data-centric models have been developed for a faster evaluation of adsorption energies compared to first-principles calculations. However, global models designed to describe as many materials as possible might overlook the very

Micro-reactor (MR) technology is known as an alternative technique for producing materials in a more sustainable way. The advantages of micro-reactors and membrane separation which are combined in membrane micro-reactors (MMR) listed as improved heat and mass transfer, high surface area to volume ratio, enhanced catalytic efficiency with no equilibrium limitation, flexibility in reactor design, a short

Microbial electrochemical processes are primary platforms for generating electricity or value-added products by relying on the interaction between electroactive microorganisms and electrodes by utilizing electron carriers like hydrogen and enzyme through the oxidation–reduction reactions. Microbial electrosynthesis (MES), initially introduced as electricity-driven bioproduction from CO2, offered a

Billingham UK, where Mike Spencer spent his entire industrial career, has long been associated with the use of steam reforming for the production of synthesis gas required for the manufacture of some important chemicals, particularly ammonia and methanol. This paper describes the steam reforming process and presents some of the history of the development of tubular reforming. The catalysts, technology

Six silica-supported phosphotungstic acid catalysts (PTA/SiO2) of different composition (20–70 wt% PTA content) have been synthesized and characterized by elemental analysis, BET, BJH, NH3-TPD methods, FT-IR spectroscopy of adsorbed pyridine and 1H MAS NMR techniques. The new composite catalysts were first applied in the Friedel–Crafts alkylation of toluene with 1-octene as a benchmark process under

Ribozymes are huge complex biological catalysts composed of a combination of RNA and proteins. Nevertheless, there is a reduced number of small ribozymes, the self-cleavage ribozymes, that are formed just by RNA and, apparently, they existed in cells of primitive biological systems. Unveiling the details of these “fossils” enzymes can contribute not only to the understanding of the origins of life

Recent advances in alkaline earth (Ae) metal hydrogenation catalysis have broadened the spectrum of potential catalysts to include candidates from the main group, providing a sustainable alternative to the commonly used transition metals. Although Ae-amides have already been demonstrated to catalyze hydrogenation of imines and alkenes, a lucid understanding of how different metal/ligand combinations

In this study, the HCOOH decomposition reaction on nickel (Ni)- and copper (Cu)-embedded graphene surfaces was computationally modeled using density functional theory. The charge density of both graphene surfaces was investigated by bader charge analysis and demonstrated by an electron density difference map. The results proved that HCOOH, HCOO, COOH, HCO, H2O, CO, OH and H structures chemically bonded

Electrocatalytic CO2 reduction (ECR) is regarded as an alternative strategy for tackling the energy demand problem as well as environmental issues such as global warming. The development of highly selective and stable, environmentally friendly, energy-efficient, and cost-natural advanced electrocatalysts is critical to facilitating this kinetically slow process. Herein, it has been aimed to form hierarchically

Cooperative multimetallic catalysis is a fascinating field of research further expanding the role of homogeneous catalysis. The simultaneous activation of two substrates or functionalities by different catalytic entities and their subsequent coupling are the responsible for the rate acceleration and selectivity exerted by these systems. The nature of the metal moieties is the responsible of the activation

The deactivation of a copper–zinc oxide catalyst has been studied in a set of parallel tests which covered a range of space-times with equal flow and variable catalyst quantity, from 1/8th bed to full bed. The activation–deactivation trends over time in different segments of the full catalyst bed have been determined by two alternative parallel difference methods. The relative trends in segmental activity

Heterogeneous catalysis is linked to industrial considerations from its origins, so is computational heterogeneous catalysis. The impact of first principles calculations on discoveries made for industrially relevant systems is growing year after year. In an innovation context, key questions are related to active site structure understanding, chemical reactivity investigations, multi-scale modeling

Electric fields produce a range of effects by interacting with atoms, molecules, and complex matter modifying the activation barriers of chemical reactions, shaping their free-energy landscapes and reaction pathways, and hence holding a crucial place in catalysis. Owing to the development of novel theories and advanced computational approaches, nowadays supercomputing resources are routinely exploited

Pursuing an environmentally friendly alternative to the Haber–Bosch process, using density functional theory (DFT) we explore further the merit of transition metal nitride (TMN) surfaces as catalysts for the nitrogen reduction reaction (NRR). Prior studies by our group have investigated the (100) and (111) facets of these TMNs and found the (100) to be favored in all cases. Many of the (100) facets

We demonstrate how a full QM/MM derivatization of the recently developed GOCAT model can be utilized in the global optimization of molecular embeddings. To this end, we provide two distinct examples: An \(\text {S}_\text {N}2\) reaction, and one enzymatic example of recent interest, the ketosteroid isomerase. These serve us to highlight the advantages of such an approach and sketch the roadmap for

The adsorption of methanol in HZSM-5 at low temperatures has long been regarded as an associative process involving hydrogen bonding to the acidic zeolite hydroxyl groups. Recent studies employing inelastic neutron scattering spectroscopy (INS) have reported that complete dissociation to methoxylate the zeolite occurs at 298 K, and infrared evidence for a partial dissociation at 298 K has also been

In the present study, a highly efficient electrochemical sensor for methadone measurement through the use of a glassy carbon electrode modified with two layers of graphene/Ag nanoparticles ((Gr/AgNPs)2/GCE) nanocomposite is introduced. The morphological, elemental and electrochemical properties of the as-prepared nanocomposite were evaluated by scanning electron microscopy, energy dispersive spectroscopy

This work investigated the potentiality of calcium oxide supported on coal fly ash (CaO/CFA) as a solid catalyst for biodiesel synthesis from Jatropha oil (JO). Synthesized CaO/CFA catalyst at various precursor salt concentrations was investigated and exhibited good activity for transesterification reaction when the 40% wt/vol. concentration of precursor salt solution was loaded on coal fly ash. The

Topotecan (TPT), a potential antitumor agent for treating various cancers (lung, ovarian, etc.), is a water-soluble camptothecin derivative compound. It is utilized in hydrochloride salt to treat ovarian cancer, lung cancer, and other types of cancer. Herein, a stable and sensitive electrochemical sensor for topotecan hydrochloride detection based on a glassy carbon electrode fabricated by 2D-MoS2/TiO2

High-throughput computational catalyst studies are typically carried out using density functional theory (DFT) with a single, approximate exchange-correlation functional. In open shell transition metal complexes (TMCs) that are promising for challenging reactions (e.g., C–H activation), the predictive power of DFT has been challenged, and properties are known to be strongly dependent on the admixture

The first-row transition metal catalysis often serves as a complementary strategy to traditional precious metal catalysis. Other than their advantages in abundance and sustainability, their unique electronic properties often give rise to more complicated reactivities. Co-catalyzed hydrogenation is an example of these relatively underexplored first-row transition metal catalysis. In this work, we will

Ceftizoxime (CFX) is used to reduce the infection caused by both gram-negative and gram-positive bacteria. In this report, a novel electrochemical sensor for CFX comprising a Cu(Him)2 nanoparticles and ionic liquid (IL) hybride modified carbon paste electrode (CPE) has been developed. The structural properties of Cu(Him)2 nanoparticles was characterized using energy-dispersive X-ray spectroscopy (EDX)

The detection of sulfamethoxazole, an antibacterial sulfonamide drug, is a very effective with antibiotic properties, and commonly used in the treatment of a variety of infections. Due to the importance in diseases treatment of humans and also of animals, the development of techniques for its quantification in body fluids is highly desirable. A voltammetric sensor is described for the determination

Methylcyclohexane (MCH) is regarded as an excellent hydrogen energy carrier due to its reasonable theoretical hydrogen storage content (6.22 wt%) and physicochemical performance. Methylcyclohexane-toluene-hydrogen (MTH) cycle realizes the recycling of materials and energy, and has a good prospect of industrial application. The dehydrogenation process is highly reversible, and the industrial hydrogenation

In continuation of our previous DFT calculations on the possibility of using the earlier transition metal nitrides for catalyzing hydrogen evolution reaction, this work analyzes the (111) facets of these surfaces which are as dominant as the (100) when a polycrystalline catalyst is manufactured. Various hydrogen coverage on these surfaces is considered, the free energy diagram and overpotentials are

Zeolite is a class of microporous crystalline materials widely used in heterogeneous catalysis. Over the past decades, theoretical simulations, particularly those based on first principles calculations, have advanced significantly the understandings on zeolite, from structure to adsorption kinetics and to catalytic reactivity. The machine learning (ML) methods developed in recent years further boost

Active electrodes of transition metal selenides attract extensive consideration in energy storage application because of its improved electrochemical performances. In this study, evolution of flower like MnSe2@MoSe2 was subsequently synthesized through one pot hydrothermal route. Growth of combined composite exposed flowerlike morphology with looser corrugated nanospikes increases surface area for

Methanol dynamics in zeolite H-ZSM-5 (Si/Al of 25) with a methanol loading of ~ 30 molecules per unit cell has been studied at 298, 323, 348 and 373 K by incoherent quasi-elastic neutron scattering (QENS). The elastic incoherent structure factor (EISF) reveals that the majority of methanol is immobile, in the range between 70 and 80%, depending on the measurement temperature. At 298 K, ≈ 20% methanol

A series of studies with sets of analogous samples was carried out to show how the technique of methanol adsorption and desorption can be used to provide useful technical information in an industrial setting. Thermal desorption of methanol and its surface reaction products (formaldehyde, dimethyl ether, CO2) offered data which could inform on the surface and even on the catalytic performance of the

The relative performance of Pt{111} and Pt{100} terraces in the enantioselective hydrogenation of ethyl pyruvate over cinchonidine-modified Pt/graphite has been investigated. Three series of 5% Pt/graphite catalysts have been prepared by sintering as-received material at temperatures in the range 400–1000 K. All underwent Pt particle growth and faceting as shown by transmission electron microscopy

The nonheme iron enzyme ScoE catalyzes the biosynthesis of an isonitrile substituent in a peptide chain. To understand details of the reaction mechanism we created a large active site cluster model of 212 atoms that contains substrate, the active oxidant and the first- and second-coordination sphere of the protein and solvent. Several possible reaction mechanisms were tested and it is shown that isonitrile

Cu/ZnO catalyst precursors for industrial methanol synthesis catalysts are traditionally synthesised by coprecipitation. In this study, a new precipitation route has been investigated based on anti-solvent precipitation using a switchable solvent system of triethylamine and water. This system forms a biphasic system under a nitrogen atmosphere and can be switched to an ionic liquid single phase under

The sequestration of atmospheric CO2 into value-added products is of great interest from economic and environmental perspectives. The tetra-shelled Cr1.3Fe0.7O3 hollow sphere as a heterogeneous catalyst was synthesized by a simple hydrothermal method followed by calcination at 600 °C. The synthesized tetra-shelled hollow spheres were characterized by several effective tools. The catalytic performance

The selective hydrogenation of lignin-derived phenols under mild conditions is still a challenging work. In this study, 2.0 wt% Pd/γ-Al2O3 catalyst was found to show high catalytic performance for the selective hydrogenation of lignin-derived phenols, giving 100% conversion of substrate and 94.9% yield of cyclohexanols under optimized conditions. The excellent catalytic performance of the 2.0 wt% Pd/γ-Al2O3

Sorption enhanced methanol production makes use of the equilibrium shift of the \(\hbox {CO}_2\) hydrogenation reaction towards the desired products. However, the increased complexity of the catalyst system leads to additional reactions and thus side products such as dimethyl ether, and complicates the analysis of the reaction mechanism. On the other hand, the unusually high concentration of intermediates

Hydrogen is recognized as an ideal substitute for conventional energy sources due to its exceptional merits. However, the lack of inexpensive and efficient hydrogen storage approaches is the main obstacle for the “Hydrogen Economy”. Liquid organic hydrogen carriers (LOHCs) are attractive due to the decoupling of energy generation and usage in both space and time. Herein, we surveyed the recent advances

As a photocatalyst responding to visible light, red phosphorus has the advantages of cheap and easy availability, low toxicity and suitable band gap. In this work, ultra-thin red phosphorus (URP) with the narrower band gap through ultrasound for 8 h was successfully synthesized. Though a series of characterization (such as: XPS analysis, photoelectric response analysis, Raman analysis, AFM images,

Considering the expansion of the use of renewable energy in the future, the technology to store and transport hydrogen will be important. Hydrogen is gaseous at an ambient condition, diffuses easily, and its energy density is low. So liquid organic hydrogen carriers (LOHCs) have been proposed as a way to store hydrogen in high density. LOHC can store, transport, and use hydrogen at high density by

Urea, as a significant molecule in biology, chemistry and agriculture, is extensively present both in industrial production and daily life. However, its excessively releasing into water and soil could bring about a serious threat to the environment and ecology due to the potential eutrophication. Considering the potential hydrogen content in urea, urea-rich wastewater is also regarded as a strategic

This paper, a tribute to Mike Spencer’s research contribution to zeolite technology, details work carried out with ICI proprietary (and other) zeolites during the late 70’s to mid- 80’s. The projects were stimulated by the 1970’s oil crises, and Mobil Oil’s publications on ZSM-5 technology, and involved a collaborative partnership between ICI Agricultural and Petrochemicals Divisions, with Mike a major

Photocatalysts capable of utilizing full-spectrum solar energy for solar hydrogen evolution are highly appealing. Although graphene-based nanocomposites show certain photocatalytic characteristics due to its excellent conductivity, as a photothermal material, studies on its photothermal conversion effect have not been valued enough so far. Herein, reduced graphene oxide/TiO2 (rGO/TiO2) was synthesized

The demand for decarbonizing the ammonia industry by using renewable energy has invoked increasing research interests into catalyst development for effective N2 reduction under mild conditions. Hydride-based materials are among some of the emerging catalysts for ammonia synthesis at ambient pressure and low temperatures (< 673 K). A recent chemical looping process based on Ni/BaH2 showed the most promise

Adsorbed hydrogen (H) species on catalyst surfaces are important active intermediates in many catalytic reactions and detailed analyses of them are necessary to understand the catalyses. Inelastic neutron scattering (INS) enables direct and selective observation of H species due to the extremely large incoherent neutron scattering cross section of a hydrogen atom. In the present study, the adsorbed

We have investigated a series of supported and unsupported nickel and cobalt catalysts, principally using neutron vibrational spectroscopy (inelastic neutron scattering, INS). For an alumina supported Ni catalyst we are able to detect hydrogen on the metal for the first time, all previous work has used Raney Ni. For an unsupported Ni foam catalyst, which has similar behaviour to Raney Ni but with a

The aqueous phase reforming of glycerol, to hydrogen, alkanes and liquid phase dehydration/dehydrogenation products, was studied over a series of 1 wt% Pt/LaMO3 (where M = Al, Cr, Mn, Fe, Co, Ni) catalysts and compared to a standard 1 wt% Pt/γ-Al2O3 catalyst. The sol–gel combustion synthesis of lanthanum-based perovskites LaMO3 produced pure phase perovskites with surface areas of 8–18 m2g−1. Glycerol