Graphene Oxide Membrane Reactor for Electrochemical Deuteration Reactions.

The deuteration of organic molecules is considerably important in organic and medicinal chemistry. An electrochemical membrane reactor using proton-conducting graphene oxide (GO) nanosheets was developed to synthesize valuable deuterium-labeled products via an efficient hydrogen-to-deuterium (H/D) exchange under mild conditions at ambient temperature and atmospheric pressure. Deuterons (D+) formed by the anodic oxidation of heavy water (D2O) at the Pt/C anode permeate through the GO membrane to the Pt/C cathode, where organic molecules with functional groups (C≡C and C═O) are deuterated with adsorbed atomic D species. Deuteration occurs in outstanding yields with high levels of D incorporation. We also achieved the electrodeuteration of a drug molecule, ibuprofen, demonstrating the promising feasibility of the GO membrane reactor in the pharmaceutical industry.

Energy Application of Graphene Based Membrane: Hydrogen Separation.

Hydrogen gas (H2 ) is a viable energy carrier that has the potential to replace the traditional fossil fuels and contribute to achieving zero net emissions, making it an attractive option for a hydrogen-based society. However, current H2 purification technologies are often limited by high energy consumption, and as a result, there is a growing demand for alternative techniques that offer higher H2 purity and energy efficiency. Membrane separation has emerged as a promising approach for obtaining high-purity H2 gas with low energy consumption. Nevertheless, despite years of development, commercial polymeric membranes have limited performance, prompting researchers to explore alternative materials. In this context, carbon-based membranes, specifically graphene-based nanomaterials, have gained significant attention as potential membrane materials due to their unique properties. In this review, we provide a comprehensive overview of carbon-based membranes for H2 gas separation, fabrication of the membrane, and its characterization, including their advantages and limitations. We also explore the current technological challenges and suggest insights into future research directions, highlighting potential ways to improve graphene-based membranes performance for H2 separations.

Light-Stimulated Luminescence Control of Lead Halide-Based Perovskite Nanocrystals Coupled with Photochromic Molecules via Electron and Energy Transfer.

Photoswitchable nanomaterials are key materials in the development of advanced imaging techniques, such as super-resolution fluorescence microscopy. The combination of perovskite CsPbBr3 nanocrystals (NCs) with bright photoluminescence (PL) emission and diarylethenes (DAEs) with structural changes in response to ultraviolet (UV) and visible light is a promising candidate system. Herein, CsPbBr3 NCs are coupled with photochromic DAE molecules to control the PL emission from the NCs by light stimulation. The PL emission is successfully switched ON and OFF by alternating UV and visible light irradiation. Time-resolved PL emission studies suggest that Förster resonance energy transfer from CsPbBr3 NCs to the closed-ring form of DAE occurs after UV irradiation, and the PL emission is quenched. Upon visible-light irradiation, DAE is converted to the open-ring isomer, and the PL emission is restored. Femtosecond pump-probe spectroscopy reveals that light stimulation induces not only energy transfer but also photoinduced electron transfer in the NC-DAE pair on the picosecond timescale to form DAE radicals. Thus, it is suggested that the holes residing in the NCs react with the NCs, degrading the PL emission. Stable PL switching is realized using 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) as a hole scavenger to avoid the reaction between the holes and NCs.

Nano-pulsed discharge plasma-induced abiotic oligopeptide formation from diketopiperazine.

Conventional oligopeptide synthesis techniques involve environmentally harmful procedures and materials. In addition, the efficient accumulation of oligopeptides under Hadean Earth environments regarding the origin of life remains still unclear. In these processes, the formation of diketopiperazine is a big issue due to the strong inhibition for further elongation beyond dipeptides. Hydrothermal media enables environmentally friendly oligopeptide synthesis. However, hydrothermal oligopeptide synthesis produces large amounts of diketopiperazine (DKP), due to its thermodynamic stability. DKP inhibits dipeptide elongation and also constitutes an inhibitory pathway in conventional oligopeptide synthesis. Here, we show an efficient pathway for oligopeptide formation using a specially designed experimental setup to run both thermal and non-thermal discharge plasma, generated by nano-pulsed electric discharge with 16-23 kV voltage and 300-430 A current within ca. 500 ns. DKP (14%) was converted to dipeptides and higher oligopeptides in an aqueous solution containing alanine-DKP at pH 4.5, after 20 min of 50 pps thermal plasma irradiation. This is the first study to report efficient oligopeptide synthesis in aqueous medium using nano-pulsed plasma (with thermal plasma being more efficient than non-thermal plasma) via DKP ring-opening. This unexpected finding is implicative to evaluate the pathway how the oligopeptides could have accumulated in the primitive Earth with high-energy plasma sources such as thunder as well as to facilitate the green synthesis of oligopeptides.

Study on Sensing Mechanism of Volatile Organic Compounds Using Pt-Loaded ZnO Nanocrystals.

Understanding the surface chemistry of target gases on sensing materials is essential for designing high-performance gas sensors. Here, we report the effect of Pt-loading on the sensing of volatile organic compounds (VOCs) with ZnO gas sensors, demonstrated by diffuse reflection infrared Fourier transform (DRIFT) spectroscopy. Pt-loaded ZnO nanocrystals (NCs) of 13~22 nm are synthesized using the hot soap method. The synthesized powder is deposited on an alumina substrate by screen-printing to form a particulate gas sensing film. The 0.1 wt% Pt-loaded ZnO NC sensor shows the highest sensor response to acetone and ethanol at 350 °C, while the responses to CO and H2 are small and exhibit good selectivity to VOCs. The gas sensing mechanism of ethanol with Pt-ZnO NCs was studied by in situ DRIFT spectroscopy combined with online FT-IR gas analysis. The results show that ethanol reacts with small Pt-loaded ZnO to produce intermediate species such as acetaldehyde, acetate, and carbonate, which generates a high sensor response to ethanol in air.

Electrochemical Detection of Ethanol in Air Using Graphene Oxide Nanosheets Combined with Au-WO3.

Detection, monitoring, and analysis of ethanol are important in various fields such as health care, food industries, and safety control. In this study, we report that a solid electrolyte gas sensor based on a proton-conducting membrane is promising for detecting ethanol in air. We focused on graphene oxide (GO) as a new solid electrolyte because it shows a high proton conductivity at room temperature. GO nanosheets are synthesized by oxidation and exfoliation of expanded graphite via the Tour's method. GO membranes are fabricated by stacking GO nanosheets by vacuum filtration. To detect ethanol, Au-loaded WO3 is used as the sensing electrode due to the excellent activity of gold nanoparticles for the catalysis of organic molecules. Au-WO3 is coupled with rGO (reduced graphene oxide) to facilitate the electron transport in the electrode. Ce ions are intercalated into the GO membrane to facilitate proton transport. The sensor based on the Ce doped-GO membrane combined with Au-WO3/rGO as a sensing electrode shows good electric potential difference (ΔV) responses to ethanol in the air at room temperature. The sensor signal reaches more than 600 mV in response to ethanol at 40 ppm in air, making it possible to detect ethanol at a few ppb (parts per billion) level. The ethanol sensing mechanism was discussed in terms of the mixed-potential theory and catalysis of ethanol on Au-WO3.

Biogasoline production from linoleic acid via catalytic cracking over nickel and copper-doped ZSM-5 catalysts.

Catalytic cracking of vegetable oil mainly processed over zeolites, and among all the zeolites particularly HZMS-5 has been investigated on wide range for renewable and clean gasoline production from various plant oils. Despite the fact that HZSM-5 offers a higher conversion degree and boost aromatics yield, the isomerate yield reduces due to high cracking activity and shape selectivity of HZSM-5. Hence, to overcome these problems, in this study the transition metals, such as nickel and copper doped over HZSM-5 were tested for its efficiencies to improve the isoparaffin compounds. The catalysts were screened with linoleic acid in a catalytic cracking reaction conducted at 450 ᵒC for 90 min in an atmospheric condition in batch reactor. Then, the gasoline composition of the organic liquid product (OLP) was analysed in terms of paraffin, isoparaffin, olefin, naphthenes and aromatics (PIONA). The results showed that Cu/ZSM-5 produced the highest liquid yield of 79.1%, at the same time reduced the production of gas and coke to 18.8% and 0.7%. Furthermore, the desired isoparaffin composition in biogasoline increased from 1.6% to 6.8% and at the same time reduced the oxygenated and aromatic compounds to 15.4% and 59.7%, respectively. The linoleic acid as model compound of rubber seed oil, in the catalytic cracking reaction provides a clearer understanding of the process. Besides, the water gas shift (WGS) reaction in catalytic cracking reaction provides insitu hydrogen production to saturate the branched olefin into the desired isoparaffin and the aromatics into naphthenes.

Synthesis of Cu2O/CuO Nanocrystals and Their Application to H2S Sensing.

Semiconducting metal oxide nanocrystals are an important class of materials that have versatile applications because of their useful properties and high stability. Here, we developed a simple route to synthesize nanocrystals (NCs) of copper oxides such as Cu2O and CuO using a hot-soap method, and applied them to H2S sensing. Cu2O NCs were synthesized by simply heating a copper precursor in oleylamine in the presence of diol at 160 °C under an Ar flow. X-ray diffractometry (XRD), dynamic light scattering (DLS), and transmission electron microscopy (TEM) results indicated the formation of monodispersed Cu2O NCs having approximately 5 nm in crystallite size and 12 nm in colloidal size. The conversion of the Cu2O NCs to CuO NCs was undertaken by straightforward air oxidation at room temperature, as confirmed by XRD and UV-vis analyses. A thin film Cu2O NC sensor fabricated by spin coating showed responses to H2S in dilute concentrations (1⁻8 ppm) at 50⁻150 °C, but the stability was poor because of the formation of metallic Cu2S in a H2S atmosphere. We found that Pd loading improved the stability of the sensor response. The Pd-loaded Cu2O NC sensor exhibited reproducible responses to H2S at 200 °C. Based on the gas sensing mechanism, it is suggested that Pd loading facilitates the reaction of adsorbed oxygen with H2S and suppresses the irreversible formation of Cu2S.

Effect of Humid Aging on the Oxygen Adsorption in SnO2 Gas Sensors.

To investigate the effect of aging at 580 °C in wet air (humid aging) on the oxygen adsorption on the surface of SnO2 particles, the electric properties and the sensor response to hydrogen in dry and humid atmospheres for SnO2 resistive-type gas sensors were evaluated. The electric resistance in dry and wet atmospheres at 350 °C was strongly increased by humid aging. From the results of oxygen partial pressure dependence of the electric resistance, the oxygen adsorption equilibrium constants (K1; for O- adsorption, K2; for O2- adsorption) were estimated on the basis of the theoretical model of oxygen adsorption. The K1 and K2 in dry and wet atmospheres at 350 °C were increased by humid aging at 580 °C, indicating an increase in the adsorption amount of both O- and O2-. These results suggest that hydroxyl poisoning on the oxygen adsorption is suppressed by humid aging. The sensor response to hydrogen in dry and wet atmosphere at 350 °C was clearly improved by humid aging. Such an improvement of the sensor response seems to be caused by increasing the oxygen adsorption amount. Thus, the humid aging offers an effective way to improve the sensor response of SnO2 resistive-type gas sensors in dry and wet atmospheres.

Pulse-driven micro gas sensor fitted with clustered Pd/SnO2 nanoparticles.

Real-time monitoring of specific gas concentrations with a compact and portable gas sensing device is required to sense potential health risk and danger from toxic gases. For such purposes, we developed an ultrasmall gas sensor device, where a micro sensing film was deposited on a micro heater integrated with electrodes fabricated by the microelectromechanical system (MEMS) technology. The developed device was operated in a pulse-heating mode to significantly reduce the heater power consumption and make the device battery-driven and portable. Using clustered Pd/SnO2 nanoparticles, we succeeded in introducing mesopores ranging from 10 to 30 nm in the micro gas sensing film (area: ϕ 150 µm) to detect large volatile organic compounds (VOCs). The micro sensor showed quick, stable, and high sensor responses to toluene at ppm (parts per million) concentrations at 300 °C even by operating the micro heater in a pulse-heating mode where switch-on and -off cycles were repeated at one-second intervals. The high performance of the micro sensor should result from the creation of efficient diffusion paths decorated with Pd sensitizers by using the clustered Pd/SnO2 nanoparticles. Hence we demonstrate that our pulse-driven micro sensor using nanostructured oxide materials holds promise as a battery-operable, portable gas sensing device.

Visible-light sensitization and photoenergy storage in quantum dot/polyoxometalate systems.

Recently, the process by which energy is transferred from photoexcited semiconductor nanocrystals, called quantum dots (QDs), to other semiconductors has attracted much attention and has potential application in solar energy conversion (i.e., QD-sensitized solar cells). Sensitization of wide band gap polyoxometalates (POMs) to visible light by using CuInS2 QDs dispersed in an organic solution is demonstrated herein. Photoluminescence quenching and lifetime studies revealed efficient electron transfer from the CuInS2 QDs to POMs, such as SiW12 O40 and W10 O32 , that were hybridized with a cationic surfactant. CuInS2 QDs function as an antenna that absorbs visible light and supplies electrons to the POMs to enable certain photocatalytic reactions, including noble-metal-ion reduction. The photoenergy storage capabilities of the QD-POM system, in which electrons photogenerated in QDs by visible-light excitation are trapped and accommodated by POMs to form reduced POM, are also demonstrated. Electrons stored in the POM can be later discharged through reductive reactions, such as oxygen reduction, in the dark.

Synthesis of Copper-Antimony-Sulfide Nanocrystals for Solution-Processed Solar Cells.

The p-type nanocrystals (NCs) of copper-based chalcogenides, such as CuInSe2 and Cu2ZnSnS4, have attracted increasing attention in photovoltaic applications due to their potential to produce cheap solution-processed solar cells. Herein, we report the synthesis of copper-antimony-sulfide (CAS) NCs with different crystal phases including CuSbS2, Cu3SbS4, and Cu12Sb4S13. In addition, their morphology, crystal phase, and optical properties were characterized using transmission electron microscopy, X-ray diffractometry, UV-vis-near-IR spectroscopy, and photoemission yield spectroscopy. The morphology, crystal phase, and electronic structure were significantly dependent on the chemical composition in the CAS system. Devices were fabricated using particulate films consisting of CAS NCs prepared by spin coating without a high-temperature treatment. The CAS NC-based devices exhibited a diode-like current-voltage characteristic when coupled with an n-type CdS layer. In particular, the CuSbS2 NC devices exhibited photovoltaic responses under simulated sunlight, demonstrating its applicability for use in solution-processed solar cells.

WO3 nanolamella gas sensor: porosity control using SnO2 nanoparticles for enhanced NO2 sensing.

Tungsten trioxide (WO3) is one of the important multifunctional materials used for photocatalytic, photoelectrochemical, battery, and gas sensor applications. Nanostructured WO3 holds great potential for enhancing the performance of these applications. Here, we report highly sensitive NO2 sensors using WO3 nanolamellae and their sensitivity improvement by morphology control using SnO2 nanoparticles. WO3 nanolamellae were synthesized by an acidification method starting from Na2WO4 and H2SO4 and subsequent calcination at 300 °C. The lamellae were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), which clearly showed the formation of single-crystalline nanolamellae with a c-axis orientation. The stacking of each nanolamella to form larger lamellae that were 50-250 nm in lateral size and 15-25 nm in thickness was also revealed. From pore size distribution measurements, we found that introducing monodisperse SnO2 nanoparticles (ca. 4 nm) into WO3 lamella-based films improved their porosity, most likely because of effective insertion of nanoparticles into lamella stacks or in between assemblies of lamella stacks. In contrast, the crystallite size was not significantly changed, even by introducing SnO2. Because of the improvement in porosity, the composites of WO3 nanolamellae and SnO2 nanoparticles displayed enhanced sensitivity (sensor response) to NO2 at dilute concentrations of 20-1000 ppb in air, demonstrating the effectiveness of microstructure control of WO3 lamella-based films for highly sensitive NO2 detection. Electrical sensitization by SnO2 nanoparticles was also considered.

Efficient photorecovery of noble metals from solution using a γ-SiW10O36/surfactant hybrid photocatalyst.

In recent years, the recovery of noble metals from waste has become very important because of their scarcity and increasing consumption. In this study, we attempt the photochemical recovery of noble metals from solutions using inorganic-organic hybrid photocatalysts. These catalysts are based on polyoxometalates such as PMo(12)O(40)(3-), SiW(12)O(40)(4-), and γ-SiW(10)O(36)(8-) coupled with a cationic surfactant, dimethyldioctadecylammonium (DODA). The three different photocatalysts dissolved in chloroform were successful in photoreducing gold ions dissolved in water in a two-phase (chloroform/water) system under UV irradiation (λ < 475 nm). The γ-SiW(10)O(36)/DODA photocatalyst exhibited the best activity and recovered gold from solution efficiently. It was suggested that one-electron reduced γ-SiW(10)O(36)(9-) formed by the UV irradiation reduced gold ions. As a result, large two-dimensional particles (gold nanosheets) were produced using the γ-SiW(10)O(36)/DODA photocatalyst, indicating that the reduction of gold ions occurred at the interface between chloroform and water. The γ-SiW(10)O(36)/DODA photocatalyst was able to recover metals such as platinum, silver, palladium, and copper from deaerated solutions. The selective recovery of gold is possible by controlling pH and oxygen concentration in the reaction system.

Single Crystallization of Cs4PbBr6 Perovskite from Supersaturated Organic Solutions Optimized Through Solubility Studies.

We demonstrate the fabrication of millimeter-sized single crystals of 0D-Cs4PbBr6 grown in a supersaturated solution consisting of organic solvents without HBr (aq). One of the precursors, CsBr, was dissolved in ethylene glycol (EG) mixed with dimethyl sulfoxide, which is a good solvent for the other precursor, PbBr2. At a solvent ratio of 20 vol % EG, the solubility of cesium bromide decreased and the title compound, Cs4PbBr6, was selectively formed, whereas, with an EG ratio of 80 vol %, 3D-CsPbBr3 was formed. A phase diagram (solubility curve) of Cs4PbBr6 in the mixed solvent containing 20 vol % EG was obtained by visually observing dissolution and crystal precipitation while changing the temperature. Because the solubility was proportional to the temperature, the solubility curve demonstrated an upper critical solution phenomenon. The solubility near the boiling point of the solution (150 °C) was approximately 0.14 M. A single crystal of Cs4PbBr6 was formed by growing a seed crystal in a supersaturated solution on the low-temperature side of the solubility curve. X-ray analysis established the crystal structure; a fluorescence emission at 520 nm with a full width at half maximum of 20 nm confirms the composition of the single crystal to be Cs4PbBr6.

Fast and selective production of quercetin and saccharides from rutin using microwave-assisted hydrothermal treatment in the presence of graphene oxide.

Rutin is a flavonoid glycoside, well-known for its antioxidant, anticarcinogenic, and cardioprotective properties. However, it exhibits lower bio absorptivity and bioactivity than its aglycon form, quercetin. Although liquid acid catalysts are conventionally utilized to obtain quercetin via rutin hydrolysis, the neutralization procedure is a major disadvantage owing to the added cost. In this study, graphene oxide (GO) was used as an alternative catalyst under microwave (MW) irradiation, owing to its easy separation from the reaction solution and high MW absorptivity, resulting in improved thermal efficiency. Two types of GOs were prepared (GO-HU using Hummer's method and GO-TO using Tour's method), and their catalytic performance for rutin hydrolysis was evaluated and compared. The highest rutin conversion (98.8 %) and quercetin yield (81.9 %) were obtained at 180 °C when the reaction was conducted for 15 min using 3 mg of GO-TO and 2400 ppm of initial rutin concentration in 50 mL of water.

Bandgap Engineering of Melon using Highly Reduced Graphene Oxide for Enhanced Photoelectrochemical Hydrogen Evolution.

The uncondensed form of polymeric carbon nitrides (PCN), generally known as melon, is a stacked 2D structure of poly(aminoimino)heptazine. Melon is used as a photocatalyst in solar energy conversion applications, but suffers from poor photoconversion efficiency due to weak optical absorption in the visible spectrum, high activation energy, and inefficient separation of photoexcited charge carriers. Experimental and theoretical studies are reported to engineer the bandgap of melon with highly reduced graphene oxide (HRG). Three HRG@melon nanocomposites with different HRG:melon ratios (0.5%, 1%, and 2%) are prepared. The 1% HRG@melon nanocomposite shows higher photocurrent density (71 µA cm-2 ) than melon (24 µA cm-2 ) in alkaline conditions. The addition of a hole scavenger further increases the photocurrent density to 630 µA cm-2 relative to the reversible hydrogen electrode (RHE). These experimental results are validated by calculations using density functional theory (DFT), which revealed that HRG results in a significant charge redistribution and an improved photocatalytic hydrogen evolution reaction (HER).

Selective Detection of CO Using Proton-Conducting Graphene Oxide Membranes with Pt-Doped SnO2 Electrocatalysts: Mechanistic Study by Operando DRIFTS.

To reduce the risk of carbon monoxide (CO) poisoning, there is a strong need for small, compact gas sensors to detect and monitor CO at ppm concentrations. In this study, we focused on detecting CO with electrochemical sensors based on proton-conducting graphene oxide (GO) nanosheets at room temperature. We found that a Ce-doped GO nanosheet membrane fitted with the sensing electrode composed of Pt (10 wt %)-doped SnO2 nanocrystals exhibits an excellent sensor response to CO at 25 °C. Pt doping of SnO2 nanocrystals has made it possible to detect CO more selectively than H2 and ethanol. The CO detection mechanism is analyzed by operando diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), Fourier transform infrared gas cell measurements, and comprehensive density functional theory-based calculations. The results revealed that adsorption of CO occurs predominantly on Pt sites, and the adsorbed CO is anodically oxidized at the interface between the sensing electrode and proton-conducting membrane, generating the selective sensor response. The strong adsorption of CO was realized with Pt (10 wt %)-doped SnO2 nanocrystals, as revealed by the DRIFTS analysis and temperature-programed desorption technique.

Facile and Green Fabrication of Microwave-Assisted Reduced Graphene Oxide/Titanium Dioxide Nanocomposites as Photocatalysts for Rhodamine 6G Degradation.

Organic pollutants, such as synthetic dyes, are treated to prevent them from contaminating natural water sources. One of the treatment methods is advanced oxidation process using a photocatalyst material as the active agent. However, many photocatalysts are hindered by their production cost and efficiency. In this study, nanocomposites consisting of reduced graphene oxide and titanium dioxide (rGO/TiO2) were prepared by a simple and green approach using the microwave-assisted method, and we utilized a graphene oxide (GO) precursor that was fabricated through the Tour method. The ratios of rGO/TiO2 in nanocomposites were varied (2:1, 1:1, and 1:2) to know the influence of rGO on the photocatalytic performance of the nanocomposites for rhodamine 6G degradation. Transmission electron microscopy (TEM) observation revealed that a transparent particle with a sheetlike morphology was detected in the rGO sample, suggesting that a very thin film of a few layers of GO or rGO was successfully formed. Based on scanning electron microscopy (SEM) observation, the rGO/TiO2 nanocomposites had a wrinkled and layered rGO structure decorated by TiO2 nanoparticles with average diameters of 125.9 ± 40.6 nm, implying that rGO layers are able to prevent TiO2 from agglomeration. The synthesized product contained only rGO and TiO2 in the anatase form without impurities that were proven by Raman spectra and X-ray diffraction (XRD). The nanocomposite with rGO/TiO2 ratio 1:2 (composite C) was found to be the best composition in this study, and it was able to degrade 82.9 ± 2.4% of the rhodamine 6G after UV irradiation for 4 h. Based on a time-resolved photoluminescence study at wavelength emission 500 nm, the average decay lifetime of R6G-rGO/TiO2 composites (2.91 ns) was found to be longer than that of the R6G-TiO2 sample (2.05 ns), implying that the presence of rGO in rGO/TiO2 composites successfully suppressed the electron-hole recombination process in TiO2 and significantly improved their photocatalytic performance. This study showed that the rGO/TiO2 nanocomposites synthesized through relatively simple and eco-friendly processes display promising prospects for photocatalytic degradation of dyes and other recalcitrant pollutants in a water stream.

Application of a solid electrolyte CO(2) sensor for the analysis of standard volatile organic compound gases.

Preparation and analysis of standard VOC (volatile organic compound) gases are needed when developing and evaluating the performance of analytical methods or instruments to detect VOCs. In this study, we designed and developed a simple system for the analysis of VOCs based on their decomposition into CO(2) by a combustion catalyst and their subsequent detection using a solid electrolyte CO(2) sensor. In this sensor, NASICON (Na(3)Si(2)Zr(2)PO(4); Na(+) conductor) and binary carbonate (Li(2)CO(3)-BaCO(3)) were used as the solid electrolyte and the sensing layer, respectively. This developed system proved to be effective in determining the concentrations of standard gases, including VOCs (ethanol, formaldehyde, and toluene), CO, and hydrocarbons in parts per million concentrations (10-500 ppm). The system also could continuously monitor the variations in ethanol vapors prepared by a diffusion method where liquid ethanol was heated at 25 and 50 degrees C. The advantages and limitations of our developed analytical system are also discussed.