Microwave-assisted One-pot Reaction Research Articles

High-Entropy Oxides as Nanozymes for Non-Immunological Electrochemical Monitoring of Cortisol

High entropy oxides (HEOs) are a class of materials that have garnered significant attention in recent years due to their potential use as catalysts in energy-related applications[1]. These materials are derived from high entropy compounds, which consist of equimolar or near equimolar ratios of multiple primary elements and have configurational entropy in the formation of a single-phase structure. The cocktail effect of HEOs gives rise to various catalytically active sites due to the synergistic interaction of the different elements, and lattice distortion during the formation of a single-phase solid solution results in the generation of abundant oxygen vacancies, which enhances the adsorption activity of HEOs and improves their catalytic performance[2]. HEOs can also be cost-efficient by utilizing low-cost transition metal elements as their active centers. Despite their widespread use as catalysts, the application of HEOs in electrocatalysis for molecule monitoring and early diagnosis remains largely unexplored.Cortisol, a glucocorticoid hormone that regulates many aspects of metabolism, stress, and immune response, is closely related to various diseases and disorders[3]. Current methods for noninvasive monitoring of cortisol relies upon immunological assays and typically limited to labor-intensive and time-consuming laboratory techniques. As a consequence, detecting cortisol in a label-free manner that is low cost and offers significant sensor stability and high sensitivity is desirable for many emerging applications, particularly for on-body monitoring.Here, we present work that examines the catalytic activities of HEOs as nanozymes for the electrocatalysis of cortisol. The electrochemical cortisol sensor is based on a novel one-pot microwave-assisted reaction synthesized (Fe, Co, Mn, Ni, Cu) Ox. The catalytic mechanism of electrochemical sensors depends on the formation of various valence metal redox species pairs, where the higher valence state oxidizes cortisol species present on the electrode surface, accompanied by a reduced lower valence state. The one-pot microwave-assisted synthesized HEOs exhibited ultra-high catalytic activity towards cortisol species as measured by cyclic voltammetry and chronoamperometry. Experimental results show a superior sensing performance including a detection limit as low as 0.5 µM (s/N=3), a good linear detection range between 0.01 ~ 4.01 µM, and a sensitivity of 46.5 µA µM-1 cm-2.

Semiconductive (Cu–S)n metal–organic framework incorporated polyimide nanocomposite coatings forming an oxide barrier for durable anticorrosion effects

A semiconductive (Cu–S)n metal–organic framework (MOF) possesses redox property, which enables polyimide (PI)/(Cu–S)n MOF nanocomposite coatings to form a passivation layer on a metal substrate to prevent corrosion. This study successfully synthesised (Cu–S)n MOF nanorods by using a one-pot microwave-assisted reaction. The functionalised (Cu–S)n MOF nanorods exhibited excellent dispersion in solution and could polymerise with the PI matrix through chemical bonding to form PI/functionalised (Cu–S)n MOF (PI/FMOF) nanocomposites. The as-prepared nanocomposites exhibited multifunctional properties with remarkable flexibility and excellent thermal, mechanical, and corrosion protection effect, as well as anticorrosion against high temperatures. The nanocomposites exhibited a corrosion rate and corrosion protection efficiency of 4.66 × 10−3 milli-inches per year and 99.93 %, respectively. Furthermore, long-term (21 days) anticorrosion durability tests revealed that the PI/FMOF nanocomposites maintained their anticorrosion performance throughout the tests. This study is the first to use polymer/redox MOF–based nanocomposites in anticorrosion applications, successfully reducing the corrosion rate and inhibiting corrosion through the induction of a passivation barrier.

Investigation of microwave assisted synthesis of Schiff Base derived Metal-Chelates by liquid invert sugar containing D-Glucose

The ethanol-soluble (6E,6'E)-6,6'-(1,2-phenylenebis(azan-1-yl-1-ylidene))dihexane-1,2,3,4,5-pentaol (LISPDA) and (E)-6-(2-hydroxyphenylimino)hexane-1,2,3,4,5-pentaol (LISAP) were investigated in this study. Condensation of 1,2-phenylenediamine and 2-aminophenol with 2,3,4,5,6-pentahydroxyhexanal (GL) in the presence of weak acid as a catalyst under mono-mode microwave heating yielded the glucose-Schiff base product. A one-pot microwave-assisted reaction in a short reaction time was required to complete the imine condensation reaction with 90% yield and no byproducts. The molecular structures of these were discovered to be in an extended conformation, with the aromatic moiety coplanar with that of the imine bond and the imine bond exhibiting trans-geometry. Schiff base metal complexes were successfully synthesized by combining 1,2-phenylenediamine and 2-aminophenol with D-glucose and Co(II), Ni(II), and Cu(II). Elemental analysis, magnetic susceptibility, thermal analysis, and electronic and infrared spectral studies were used to determine the structural assessment of ML2 complexes.

Investigating the Anticancer Activity of Novel Norethindrone Derivatives in PC3 Prostate Cancer Cells

It is estimated that over 248,000 new cases of prostate cancer will be diagnosed this calendar year (2021) representing upwards of 20% of newly diagnosed cancer cases in men.1,2 Despite these numbers, prostate cancer‐related deaths have significantly declined over the period of time from 1993 to 2016, yet prostate cancer was expected to be responsible for almost 10% of cancer‐related deaths in 2018.1 Metastasis and cancer cell resistance results in treatment failure and progressive disease, and this remains a significant concern in the care of men with prostate cancer.To address the significant need for novel agents in the treatment of resistant prostate cancer, we designed and synthesized a small library of norethindrone (NE) derivatives with varying substituents attached to the 17‐position (Compounds A‐D) with the hopes of identifying androgen receptor antagonists. Click chemistry was utilized to facilitate the formation of a triazole linking NE to alkyl and aryl substituents. The corresponding azides were synthesized in situ from alkyl bromides or aryl bromides in a one‐pot microwave‐assisted reaction in an Anton Parr Monowave‐50 reactor at 150℃ for 20 minutes.Here we present initial data of our small library of NE derivatives which were screened for anticancer activity using the XTT cell viability assay in PC3 prostate cancer cells. Two of the compounds (A and D) failed to induce an anticancer response. Compound B demonstrated weak anticancer activity with an IC50 of greater than 100 µM, whereas Compound C demonstrated low micromolar activity with an IC50 of 19 µM. Further studies are ongoing to determine the mechanism(s) by which Compound C elicits its anticancer activity in the metastatic‐derived PC3 prostate cancer cells. Additionally, these results will assist with further rational design using NE as a scaffold in an attempt to increase the potency against PC3 and other prostate cancer cell lines.1. American Cancer Society. Cancer Facts & Figures 2021. Atlanta: American Cancer Society; 20212. Siegel RL, Miller KD, Jemal A. Cancer statistics, 2019. CA Cancer J Clin. 2019 Jan;69(1):7‐34. doi: 10.3322/caac.21551. Epub 2019 Jan 8. PMID: 30620402.

Microwave Reaction Improved Heterocyclization of Quinazolinone Ring in Synthesis of Erlotinib Analogues

Background Tinibs were a kind of important epidermal growth factor receptor (EGFR) inhibitors used as potential therapeutic agents in treating non-small cell lung cancer (NSCLC) in clinic. The drug resistance of clinical used tinibs made the development of more active tinib analogues an attractive field in research. Quinazoline ring was regarded as the key fragment in tinibs and was indispensible intermediate in the synthesis of quinazoline. Thus, synthesis of intermediates was a key step which would further limit the overall yield of final product of tinib analogues. However, the commonly used synthetic scheme was somewhat complicated and time consuming with relatively low yield in heterocylization of and its derivatives. Aim In this work, we intended to explore an effective way to improve synthesis of heterocyclization of 6,7-bis(2-methoxyethoxy)quinazolin-4(3H)-one (compound 5), the key fragment of erlotinib analogues, in both reaction procedure and yield, thus to provide reference to synthesis of other derivatives. Methods A simple microwave-assisted one-pot reaction was employed to improve the synthesis of heterocyclization of ring. The reaction conditions, including microwave power, temperature and time of reaction, were screened to achieve high yield under simple operation. Results 6,7-bis(2-methoxyethoxy)quinazolin-4(3H)-one (compound 5) was successfully synthesized from starting material of 4,5-bis(2-methoxyethoxy)-2-nitrobenzonitrile by microwave reaction, which was finished in 1 hour just by one step. The yield of heterocyclization was increased from 29.8% of commonly used three-step scheme to 50% herein. Conclusion Microwave reaction efficiently improved synthesis of heterocyclization of 6,7-bis(2-methoxyethoxy)quinazolin-4(3H)-one into quinazolinone in both synthetic procedure and yield. The results may provide valuable reference to synthesis of other derivatives.

Screening of Natural Deep Eutectic Solvents for Green Synthesis of 2-methyl-3-substituted Quinazolinones and Microwave-Assisted Synthesis of 3-aryl Quinazolinones in Ethanol

In this study, two fast and efficient protocols for green synthesis of 3-substituted quinazolinones were perfomed. A synthesis of 2-methyl-3-substituted quinazolinones was performed in natural deep eutectic solvents, while 3-aryl quinazolinones were obtained by using microwave assisted synthesis. Benzoxazinone, which was used as an intermediate in the synthesis of 2-methyl-3-substituted quinazolinones, was prepared conventionally from anthranilic acid and acetic anhydride. In order to find the most appropriate synthetic path, twenty natural deep eutectic solvents were applied as a solvent in these syntheses. Choline chloride:urea (1 : 2) was found to be the most efficient solvent and was further used in the synthesis of 2-methyl quinazolinone derivatives (2–12). 3-Aryl quinazolinones (13–17), on the other hand, were synthesized in one-pot microwave-assisted reaction of anthranilic acid, different amines and trimethyl orthoformate. All compounds were synthesized in good to excellent yields, characterized by LC-MS/MS spectrometry and 1H- and 13C-NMR spectroscopy.

One-Pot CuO-Catalyzed Green Synthesis of N(N′)-Arylbenzamidines as Potential Enzyme Inhibitors

Ten N(N′)-arylbenzamidines were synthesized in 60–77% yield by one-pot microwave-assisted reaction of the corresponding N-arylbenzamides with aniline or ammonia in the presence of copper(II) oxide powder. The synthesized compounds were evaluated in vitro for inhibitory activity against several enzymes, namely acetylcholinesterase, butyrylcholinesterase, lipoxygenase, α-glucosidase, urease, and reverse transcriptase. Some compounds showed very good acetylcholinesterase and butyrylcholinesterase inhibitory activity. N′-(1,3-Benzothiazol-2-yl)- and N′-(1,3,4-thiadiazol-2-yl)benzamidines were the most active α-glucosidase inhibitors with IC50 values of 134.2 and 244.57 µM, respectively. N′-(1,3-Benzothiazol-2-yl)benzamidine also inhibited urease. Most of the obtained compounds showed inhibitory activity against reverse transcriptase (anti-HIV activity), presumably due to intermolecular hydrogen bonding, good solubility, and hydrophilicity.

Regioselective synthesis of pyrimidine-fused tetrahydropyridines and pyridines by microwave-assisted one-pot reaction.

A regioselective three-component reaction of α,β-unsaturated aldehydes, cyclic 1,3-dicarbonyls and 6-aminouracils in the presence of FeCl3·6H2O as catalyst under microwave irradiation has been demonstrated. Three-component reaction of α,β-unsaturated aldehydes like cinnamaldehyde/crotonaldehyde, cyclic 1,3-diketones such as 2-hydroxy-1,4-naphthaquinone/dimedone and 6-aminouracils provides regioselective pyrimidine-fused tetrahydropyridines tethered with cyclic 1,3-diketones. On the other hand, replacing cyclic 1,3-diketones by 4-hydroxycoumarin and keeping all other conditions the same provided a two-component pyrimidine-fused pyridines. The salient features of this methodology are operational simplicity, short reaction time, good-to-moderate yields of the products, easy purification method and regioselective products having medicinally important heterocyclic rings such as pyrimidine, tetrahydropyridine or pyridine.

Identification of the 2-Benzoxazol-2-yl-phenol Scaffold as New Hit for JMJD3 Inhibition.

JMJD3 is a member of the KDM6 subfamily and catalyzes the demethylation of lysine 27 on histone H3 (H3K27). This protein was identified as a useful tool in understanding the role of epigenetics in inflammatory conditions and in cancer as well. Guided by a virtual fragment screening approach, we identified the benzoxazole scaffold as a new hit suitable for the development of tighter JMJD3 inhibitors. Compounds were synthesized by a microwave-assisted one-pot reaction under catalyst and solvent-free conditions. Among these, compound 8 presented the highest inhibitory activity (IC50 = 1.22 ± 0.22 μM) in accordance with molecular modeling calculations. Moreover, 8 induced the cycle arrest in S-phase on A375 melanoma cells.

One-pot synthesis of color-tunable copper doped zinc sulfide quantum dots for solid-state lighting devices

Color-tunable semiconductor quantum dots (QDs) are highly attractive for a wide range of applications including imaging, sensing, and lighting. Herein, we reported a facile synthesis of copper-doped zinc sulfide quantum dots (ZnS:Cu QDs) with tunable emission colors, using a microwave-assisted one-pot reaction. 3-mercaptopropionic acid (MPA) was used as a stabilizer agent and sulfide source for the formation of ZnS:Cu QDs. The photoluminescence of ZnS:Cu QDs showed a clear red-shift as increasing Cu concentration, which can be controlled by microwave irradiation time. As increasing the irradiation time, the emission color (peak) of ZnS:Cu QDs changed from blue (500 nm) to green (540 nm), yellow (580 nm), and to orange-red (595 nm). The obtained ZnS:Cu QDs were highly luminescent, as evidenced by their high quantum yields. The potential utility of ZnS:Cu QDs as a novel lighting source was demonstrated in a near-UV chip-based white light-emitting diode.

A dual colorimetric and SERS detection of Hg2+ based on the stimulus of intrinsic oxidase-like catalytic activity of Ag-CoFe2O4/reduced graphene oxide nanocomposites

Mercuric ion (Hg2+) is a toxic metal ion in the environment, which will seriously damage the people's health. Therefore, the simple sensitive detection of Hg2+ is of great significance. In this work, Ag-CoFe2O4/reduced graphene oxide (rGO) nanocomposites were synthesized via a one-pot microwave-assisted reaction, which can directly oxidize 3, 3′, 5, 5′-tetramethylbenzidine (TMB) to produce a light blue. Then we have developed a dual colorimetric and SERS detection of Hg2+ based on the stimulus of intrinsic oxidase-like catalytic activity of Ag-CoFe2O4/rGO nanocomposites. It is demonstrated that the interaction between Hg2+ and Ag nanoparticles can occur in a short time, which includes the formation of Ag-Hg alloy due to the reduction of Hg2+. In addition, the formation of such alloy can enhance the oxide-like activity, which makes the detection of Hg2+ more sensitive. By using the SERS detection approach, the assay can detect Hg2+ as low as 0.67 nM. This detection ability is much better than previous reports based on the enzyme-like catalytic reaction, which is also lower than the maximum value of Hg2+ permitted in drinking water by the World Health Organization (WHO) (30 nM) and United States Environmental Protection Agency (EPA) (10 nM). In addition, this detection system also shows an excellent selectivity toward Hg2+ due to the affinity of Hg to Ag-CoFe2O4/rGO nanocomposites. Therefore, this approach is potentially applicable for the sensitive determination of Hg2+ in real environmental conditions.

Synthesis of InSb nanocrystals in an air atmosphere and their photocatalytic activity from near-infrared to ultra-violet

We report a new facile route to prepare indium antimonide (InSb) nanocrystals (NCs) in air and at ambient pressure. Spherical cubic zinc blende InSb NCs with an average size of 5nm were synthesized and spontaneously separated through a rapid microwave-assisted one-pot reaction. The photocatalytic activity of obtained product was investigated by the decolorization of methyl orange dye under near-IR, visible light, and UV irradiation. This novel synthetic pathway may improve existing applications and suggest new opportunities for studying III-V semiconductor nanomaterials.

Improved microwave-assisted catalyst-free synthesis of 9-aryl-5,9-dihydropyrimido[4,5-d][1,2,4]triazolo[1,5-a]pyrimidine-6,8(4H,7H)-dione derivatives

Abstract A green regioselective synthesis of some new and known 9-aryl-5,9-dihydropyrimido[4,5-d][1,2,4]triazolo[1,5-a]pyrimidine-6,8(4H,7H)-diones has been described via the microwave-assisted one-pot reaction of 3-amino-1H-1,2,4-triazoles, aromatic aldehydes and barbituric acids under solvent- and catalyst-free conditions. This operationally simple procedure is less laborious and provides a better scope than previously reported procedures.

Microwave-assisted synthesis of condensed 1,4-dihydropyridines as potential calcium channel modulators

This study reports the design, synthesis, and calcium channel modulatory activity evaluation of a series of 14 novel fused 1,4-dihydropyridine derivatives. The molecular design of the compounds was based on modifications of nifedipine, which is a calcium channel blocker. The compounds were achieved by one-pot microwave-assisted reaction of 4,4-dimethyl-1,3-cyclohexanedione, 5-chlorosalicylaldehyde/3,5-dichlorosalicylaldehyde, an appropriate alkyl acetoacetate, and ammonium acetate in ethanol according to a modified Hantzsch reaction. The structures of the compounds were confirmed by spectral methods and elemental analysis. To evaluate their relaxant activities, the maximum relaxant response (E$_{\max})$ and pD$_{2}$ values of the compounds and nifedipine were determined on isolated rat aorta rings. The obtained results indicated that all compounds produced concentration-dependent relaxation on the rings possibly due to the blockade of calcium channels. The E$_{\max}$ values (a measure of efficacy) of five compounds were higher than those of nifedipine.

Strategy and mechanism for controlling the direction of defect evolution in graphene: preparation of high quality defect healed and hierarchically porous graphene

In this paper, a novel approach for controlling the direction of defect evolution in graphene through intercalation of organic small molecules into graphite oxide (GO) combined with a one-pot microwave-assisted reaction is reported. By using ethanol as intercalator, the bulk production of high quality graphene with its defects being satisfactorily healed is achieved. The repair of defects using extraneous carbon atoms and the hybrid state of these carbon atoms are definitely demonstrated using isotopic tracing studies with (13)C-labeled ethanol combined with (13)C solid-state NMR. The defect healed graphene shows excellent crystallinity, extremely low oxygen content (C : O ratio of 23.8) and has the highest sheet conductivity (61 500 S m(-1)) compared to all other reported graphene products derived from GO. By using methanol or benzene as intercalators, hierarchically porous graphene with a self-supported 3-dimensional framework (∼917 m(2) g(-1)) containing both macropores and mesopores (2-5 nm) is obtained. This graphene possesses a distinctive amorphous carbon structure around the edge of the nanopores, which could be conducive to enhancing the lithium storage performance (up to 580 mA h g(-1) after 300 cycles) when tested as an anode of lithium ion batteries, and might have promising applications in the field of electrode materials, catalysis, and separation, and so on. The mechanism involved for the controlled defect evolution is also proposed. The simple, ultrafast and unified strategy developed in this research provides a practical and effective approach to harness structural defects in graphene-based materials, which could also be expanded for designing and preparing other ordered carbon materials with specific structures.

Supramolecular self-assembly of morphology-dependent luminescent Ag nanoclusters.

Self-assembled thiolated Ag nanoclusters (NCs) were facilely synthesized through one-pot microwave-assisted reaction. By the mechanism of aggregation induced emission, the quantum yield of the AgNCs is as high as 25.6%. The as-prepared AgNCs give access to intriguing photophysical features and multicolour emission, which are found to be related to their fascinating supramolecular structures.

Special microwave‐assisted one‐pot synthesis of low loading Pt–Ru alloy nanoparticles on reduced graphene oxide for methanol oxidation

Published in Micro & Nano Letters; Received on 5th September 2013; Revised on 27th November 2013; Accepted on 10th December 2013In this reported work, low loading Pt–Ru alloy nanoparticles (PtRu NPs) have been highly dispersed on reduced graphene oxide (PtRu/RGO)via an auto-power adjusting microwave-assisted one-pot reaction process. The transmission electron microscopy result shows that PtRu NPswith a mean size of ∼2.99 nm decorated uniformlyon RGO. The prepared PtRu/RGO is used as an electrocatalyst for the methanol oxidationreaction (MOR). Compared with the commercial carbon-supported Pt–Ru alloy electrocatalyst, the PtRu/RGO composites demonstrate higherelectrochemical active surface area and excellent electrocatalytic activity towards the MOR, such as higher peak current density, lower onsetpotential and long-term stability. It is deduced that the good performance of the PtRu/RGO towards methanol oxidation could be attributed tothe characterised RGO support which provides more effective support and enhances the utilisation of the PtRu clusters, and to the highlydispersed small Pt–Ru alloy NPs resulting from the special microwave heating mode and lower synthesis temperature, which subsequentlyleads to a valid bifunctional mechanism between Pt and Ru. The present study proves that the PtRu/RGO composites could be apromising alternative catalyst for direct methanol fuel cells and this effective preparation method can be widely applied to other metal/bimetal NPs.1. Introduction: Fuel cells, one of the most promising alternativeenergies for the near future, have been receiving increasedattention recently because of the depletion of fossil fuels and theincrease in environmental pollution. Among them, directmethanol fuel cells (DMFCs) which have greater potentialapplication in power electric vehicles and portable electronicdevices, are excellent green power sources because of their highenergy density, low pollutant emission, low operating temperatureand ease of handling liquid methanol fuel [1–5]. However, thelack of highly efficient and inexpensive anodic catalysts is alwaysone of the most important reasons to block the commercialapplication of the DMFC. At present, platinum-based (Pt-based)electrocatalysts are still the most commonly used electrocatalystsfor both the anode and the cathode in the DMFC towards oxygenreduction and the methanol oxidation reaction (MOR), but thehigh cost, the poor utilisation and the easy-poisoning of the Ptcatalysts seriously limit their practical application in the DMFC.To solve these problems, significant efforts are currently under-way to find alternative DMFC electrocatalysts with low cost andhigh efficiency. On the one hand, to reduce the cost and enhancetheutilisation,allkindsofsupportsareused todispersethePtnano-particles (NPs), especially the carbon allotropes because of theirdifferent structures and properties from each other, such as single-walled carbon nanotubes [6], multiwalled carbon nanotubes [7],cup-stacked-type carbon nanotubes [8], mesoporous carbon [9]and graphitic carbon nanofibres [10]. Among these carbon mater-ials, graphene has attracted great attention in the nanosciencebecauseofitsoutstandingproperties[11–14].Thismaterialexhibitspromising potential application in the electrochemistry field, suchas nanoeletronics, sensors, composites, batteries, supercapacitorsand hydrogen storage [15, 16], especially as a new considerablecatalyst support to enhance electrocatalytic activity [17–20].Although many reports provide their methods to load the Pt NPson the graphene sheets, the facile preparation of the size-controland the low loading of the Pt NPs is still challenging.On the other hand, the Pt catalysts are readily poisoned by theCO

Microwave-Assisted One-Pot Synthesis of Isoquinolines, Furopyridines, and Thienopyridines by Palladium-Catalyzed Sequential Coupling–Imination–Annulation of 2-Bromoarylaldehydes with Terminal Acetylenes and Ammonium Acetate

A palladium-catalyzed microwave-assisted one-pot reaction for the synthesis of isoquinolines is developed. The reaction is carried out by sequential coupling-imination-annulation reactions of ortho-bromoarylaldehydes and terminal alkynes with ammonium acetate, and a variety of substituted isoquinolines, furopyridines, and thienopyridines is prepared in moderate to excellent yields (up to 86%).

A Bioinspired Ugi/Michael/Aza‐Michael Cascade Reaction in Aqueous Media: Natural‐Product‐like Molecular Diversity

Whole in one! A one-pot microwave-assisted reaction sequence that consists of an Ugi/Michael/aza-Michael transformation gives access to quaternary spirocenters leading to Amaryllidaceae and Erythrina alkaloid like compounds (see scheme). The process produces four stereogenic centers and six contiguous bonds, and provides products with good to excellent yields and appreciable diastereoselectivity.

Microwave-assisted one-pot synthesis of metal/metal oxide nanoparticles on graphene and their electrochemical applications

An effective synthesis strategy of hybrid metal (PtRu)/metal oxide (SnO 2) nanoparticles on graphene nanocomposites is developed using a microwave-assisted one-pot reaction process. The mixture of ethylene glycol (EG) and water is used as both solvent and reactant. In the reaction system for the synthesis of SnO 2/graphene nanocomposite, EG not only reduces graphene oxide (GO) to graphene, but also results in the formation of SnO 2 facilitated by the presence of a small amount of water. On the other hand, in the reaction system for preparation of PtRu/graphene nanocomposites, EG acts as solvent and reducing agent for reduction of PtRu nanoparticles from their precursors and reduction of graphene from graphene oxide. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) characterizations confirm the feasibility of the microwave-assisted reaction system to simultaneously reduce graphene oxide and to form SnO 2 or PtRu nanoparticles. The as-synthesized SnO 2/graphene hybrid composites show a much higher supercapacitance than the pure graphene, and the as-prepared PtRu/graphene show much better electrocatalytic activity for methanol oxidation compared to the commercial E-TEK PtRu/C electrocatalysts.