Changes In Potential Difference Research Articles

Variations in the optical and thermoelectric behavior of ZnCo2O4 nanostructures as a function of synthesis temperature

Zinc cobalt oxide nanostructures were synthesized by electrochemical deposition of zinccobalt alloy at various bath temperatures (15, 30, 45 and 60 ˚C) and its hydrothermal oxidation at 100 ˚C. X-ray diffraction pattern and Raman spectroscopy data reveals the formation of spinal structure of ZnCo2O4. Photoluminescence spectra of the samples exhibit broad peaks with a red shift in the emission energy. Diffused reflectance spectroscopy measured the band gap of the synthesized materials; band gap is 3.06, 3.03, 3.02 and 2.99 eV, for samples electrodeposited at 15, 30, 45 and 60 ˚C, respectively. Optical conductivity of synthesized materials decreases with increasing deposition layers while reflectance shows opposite trend. Thermoelectric set up measures the change in potential difference through synthesized materials when different temperatures are applied and an increment in potential were observed. Seebeck co-efficient and power factor are also studied as function of bath temperature.

Unveiling the tunable electronic, optoelectronic, and strain-sensitive gas sensing properties of Janus ZrBrCl: Insights from DFT study

Janus monolayers materials exhibit extraordinary physical and chemical properties because of crystal field changes caused by their asymmetric structures. Here, we investigate the electronic, switching, optoelectronic, and strain-sensitive gas-sensing properties of a Janus ZrBrCl monolayer via density-functional theory and the nonequilibrium Green’s function methods. The electronic properties can be tuned by applying biaxial strain and electric fields. In particular, the band gap can be changed from indirect to direct via applied a + 8 % biaxial tensile strain. It can be transformed from a semiconductor to a metal with an applied −14 % biaxial compressive strain, with a 1011 switching ratio. In addition, a biaxial strain and an electric field can modulate visible light absorption and photocurrents. Under a −12 % biaxial compressive strain, the absorption coefficient increased to 5.26 × 105 cm−1 from the intrinsic 4.08 × 105 cm−1. Across biaxial strains from −4% to + 4 %, the photocurrent density peak displayed red and blue shifts, respectively, with increasing tensile and compressive strains. NH3, NO2, and NO physically adsorb on the Br side of the ZrBrCl monolayer. Maximum gas sensitivity values of a ZrBrCl sensor are 52 % in the zigzag direction and 21 % in the armchair direction. After application of the −14 % biaxial strain, the maximum values respectively increased to 76 % and 179 %. The biaxial compressive strain-sensitive gas-sensing properties are driven by changes in the electrostatic potential difference between the Br and Cl surfaces. These findings indicate promising candidate materials for high-performance switching and optoelectronic devices, and also provide a strategy for improved gas sensors.

Research on a new type of ureteral stent material Zn-2Cu-0.5Fe-xMn with controllable degradation rate

The placement of ureteral stents plays a crucial role in the treatment of ureteral strictures, therefore requiring high material performance standards. In addition, depending on the etiology of ureteral strictures, there are significant differences in the retention time of ureteral stents, thus requiring different degradation rates for the stents. Therefore, it is crucial to develop stent materials with high performance and controllable degradation rates. This study explores the potential of Zn-2Cu-0.5Fe-xMn alloy as a ureteral stent material, utilizing the antibacterial effect of copper ions, the strengthening effect of Fe element on Zn-based alloys, and the accelerated degradation effect of Mn element. The research found that with the increase in Mn content, the average grain size of the alloy and the size of (Fe, Mn)Zn13 phase gradually increased, leading to a decrease in hardness. The corrosion rate of the alloy increased with the increase in Mn content, attributed to changes in grain size and standard electrode potential differences between elements. Due to the antibacterial effects of Zn ions and Cu ions, the Zn-2Cu-0.5Fe-xMn alloy exhibits good anti-stone formation capabilities. Furthermore, the alloy also demonstrates acceptable cytotoxicity. Therefore, the Zn-2Cu-0.5Fe-xMn alloy is expected to become an important implant material in urological surgery.

Type-dependent hot carrier behavior in photoelectrochemical reduction and oxidation of Au/GaN junction photoelectrodes

In junctions with semiconductors, plasmonic metal nanoparticles (NPs) can be utilized to efficiently harness solar energy by collecting hot carriers. However, the behavior of hot carriers at the interfaces between semiconductors with opposite doping types is not fully elucidated. Here, Au NPs are attached to n-doped (Au/n-GaN) or p-doped gallium nitrides (Au/p-GaN) to examine the photoelectrochemical performance regarding hot carrier behavior. Direct surface potential measurements revealed that electrons are collected in n-type GaN (n-GaN) when illuminated, while hot holes remain in Au NPs for oxidation reactions via the plasmonic process. Conversely, holes are collected in p-type GaN (p-GaN), thereby promoting the reduction reaction by the electrons left in Au NPs. Specifically, the change in surface potential difference induced by green light illumination in Au/p-GaN is four times greater than that observed in Au/n-GaN. Conversely, the changes in open-circuit potential and photocurrent density under light illumination are approximately six times more significant in Au/n-GaN compared to Au/p-GaN. This difference in efficiency can be attributed to the more favorable oxidation reaction occurring in Au NPs at the interface with GaN materials, as opposed to the reduction reaction, due to the difference in band alignment between the Au/GaN junction systems.

Revisitation of reactive direct current magnetron sputtering discharge: Investigation of Mg–CF4, Mg–O2, and Ti–O2 discharges by probe measurements

The reactive direct current (DC) magnetron sputtering discharges of Mg–CF4, Mg–O2, and Ti–O2 were investigated using probe measurements as a function of reactive gas flow ratio. The emission spectroscopy, which was conducted before the probe measurements, demonstrates that all the three DC discharges transit from nonreactive to reactive discharge mode with increasing reactive gas flow ratio. The probe measurements show that the plasma potentials of the Mg–O2 and Ti–O2 DC discharges slightly increase or remain almost constant with increasing reactive gas flow ratio, whereas that of the Mg–CF4 DC discharge drastically decreases at the mode transition. For the same change in reactive gas flow ratio, the discharge voltage of the Mg–CF4 DC discharge slightly increases and that of the Mg–O2 DC discharge drastically increases at the mode transition, whereas that of the Ti–O2 DC discharge slightly decreases at the mode transition. The changes in the cathode sheath potential difference at the mode transition differ between the Mg–CF4 and Ti–O2 DC discharges and the Mg–O2 DC discharge because of the difference in the probability of secondary electron emission at the cathode surface; furthermore, the changes in the anode sheath potential difference at the mode transition differ between the Mg–CF4 DC discharge and the Mg–O2 and Ti–O2 DC discharges because of the difference in the probability of negative-ion formation in the plasma bulk. The most informative results obtained in this study were the differences in the potential differences at the cathode and anode sheaths among the Mg–CF4, Mg–O2, and Ti–O2 DC discharges. They well demonstrated the effects of the change in secondary-emitted species at the cathode surface and the change in reactive gas concentration in the plasma on the potential configuration.

Changes in DC Potential Difference and Carbon Fiber Position during Cyclic Bending of Unidirectional Prepreg

Changes in DC Potential Difference and Carbon Fiber Position during Cyclic Bending of Unidirectional Prepreg

Work function analysis of photo-enhanced triethylamine adsorption impact on Au embedded CeO2 coated ZnO hybrid nanostructures: An investigation by scanning kelvin probe

This article utilizes a scanning kelvin probe to examine the impact of visible light and volatile organic compounds (VOCs) on an organic/inorganic/noble metal hybrid sensing layer. ZnO/Poly/CeO2/Poly/Au hybrid nanostructures were prepared on ITO substrate by layer-by-layer coating technique. In this case, PAH and DS polymers act as binders. The assembly of Au nanorods (NRs) on the polymer-coated ZnO NRs incorporated with CeO2 nanoparticles (NPs) and its maximum absorbance in the visible light region were studied by the structural and optical characterizations, respectively. The hybrid sensor's optical properties allowed for sizable changes in contact potential difference (CPD) when exposed to light. Although a non-selective interaction was observed, the increased responsiveness to Triethylamine (TEA) under visible light creates coordination bonds between the hybrid molecules. Notably, the surface charge was tuned in the surface of the sensing layer by varying the surfactant to explore the TEA responsiveness. Intriguingly, ZnO/Poly/CeO2 (+) has demonstrated improved adsorption capability towards TEA under irradiation due to the surface oxygen vacancies compared to ZnO/Poly/CeO2 (-). Also, ZnO/Poly/CeO2 (+) exhibited higher selectivity at adsorbing TEA than either ethanol or n-hexane.

Recognition of motor intentions from EEGs of the same upper limb by signal traceability and Riemannian geometry features.

The electroencephalographic (EEG) based on the motor imagery task is derived from the physiological electrical signal caused by the autonomous activity of the brain. Its weak potential difference changes make it easy to be overwhelmed by noise, and the EEG acquisition method has a natural limitation of low spatial resolution. These have brought significant obstacles to high-precision recognition, especially the recognition of the motion intention of the same upper limb. This research proposes a method that combines signal traceability and Riemannian geometric features to identify six motor intentions of the same upper limb, including grasping/holding of the palm, flexion/extension of the elbow, and abduction/adduction of the shoulder. First, the EEG data of electrodes irrelevant to the task were screened out by low-resolution brain electromagnetic tomography. Subsequently, tangential spatial features are extracted by the Riemannian geometry framework in the covariance matrix estimated from the reconstructed EEG signals. The learned Riemannian geometric features are used for pattern recognition by a support vector machine with a linear kernel function. The average accuracy of the six classifications on the data set of 15 participants is 22.47%, the accuracy is 19.34% without signal traceability, the accuracy is 18.07% when the features are the filter bank common spatial pattern (FBCSP), and the accuracy is 16.7% without signal traceability and characterized by FBCSP. The results show that the proposed method can significantly improve the accuracy of intent recognition. In addressing the issue of temporal variability in EEG data for active Brain-Machine Interfaces, our method achieved an average standard deviation of 2.98 through model transfer on different days' data.

Role of concentration and hydrophobic nature of weak polyelectrolytes on adsorption structure and thermodynamics at oil-water interface: Study of several carboxylate polymers

Intermolecular structure, conformations, solvation and adsorption characteristics of four partially ionized polycarboxylic acids syndiotactic-poly(acrylic acid) (s-PAA), syndiotactic-poly(methacrylic acid) (s-PMA), isotactic-poly(methacrylic acid) (i-PMA) and atactic-poly(ethacrylic acid) (a-PEA) at oil (CCl4) - water interface is studied by molecular dynamics simulations over the range from dilute to monolayer coverage. Linearity and slope of Θ-Γ curves are correlated to conformational invariance and extent of adsorption (partial vs complete) respectively, within the range of concentration of study. Adsorption of i-PMA and a-PEA chains occurs deeper into the oil-side of interface region as driven by the greater hydrophobicity of these polymers. Higher tendency of highly extended s-PMA to desorb from the interface as compared to strong adsorption of compact coiled i-PMA is driven by their solvation behavior dictated by aspects of structural partitioning of chemical groups with respect to the solvents of the two phases. Hydrophobic side-group in the polyelectrolyte chain is responsible for the slower dynamics of the backbone. The observed variation in thickness of adsorbed layer and fractional interface coverage with concentration suggest partial adsorption of chain segments beyond saturation of interface rather than coiling of chains to accommodate additional chains. While a-PEA exhibits greater variation in interfacial tension, the change in electric potential difference across the interface indicates weak adsorption by s-PMA. The influence of the tacticity of PMA on dynamics and distribution of counter-ions is in agreement with experimental results. Results provide a significant advancement in our understanding of polyelectrolyte and polymer adsorption at oil-water liquid interface.

Dynamics of potential difference changes in a biocomposite microsection for different temperature gradients

The method of formalized modeling revealed the complex nature of the dependence of the parameters of the process of rearrangement of the biocomposite microstructure on the temperature gradient. Based on the analysis of the dynamics of changes in the potential difference formed along the thickness of the birch wood microcut, the parameters of the biocomposite polarization process for various temperature gradients have determined.

Using Ambient Pressure Photoelectron Spectroscopy to Investigate the Time Dependence of Electrostatic Potential Difference over the Interphase between an Electrode and an Electrolyte

Ambient pressure photoelectron spectroscopy (APPES) is a method well-suited for measuring the change ∆φ in electrostatic potential difference φ over an interphase between an electronic conductor and an insulator. APPES had previously been used to compare ∆φ over an interphase between an electrode and an electrolyte with the change in electrochemical potential difference ∆UWE-RE between the working and the reference electrode UWE-RE .[1] The relationship between ∆φ and ∆UWE-RE at low current-transient had been shown to follow two distinct trends depending on whether charge transfer of Li+ ions between an electrode and an electrolyte occurs or not.[1,2] In this work, APPES was used to investigate the time dependence of ∆φ after changing UWE-RE . The studied electrochemical system consisted of Au (working electrode), Li4Ti5O12 (reference electrode) and a second Li4Ti5O12 (counter electrode) with 0.008 M LiClO4 in propylene carbonate (PC) as the electrolyte. Pressure in the sample compartment was equal to the saturated PC pressure. APPES experiments were performed at HIPPIE beamline at MAX IV in Lund and were conducted as follows. After applying a potential step ∆UWE-RE , a C 1s spectrum was measured every 7 s. Incident photon energy was 1800 eV. Each spectrum was fitted using a Python code written especially for the obtained C 1s spectra. Time dependence of ∆φ was extracted from the shift in the kinetic energy ∆KE of the C=O peak (∆φ = ∆KE). Experiments were performed in both regimes, i.e. when the working electrode behaves as an ideal polarizable electrode and when it behaves as an ideal non-polarizable electrode, and have shown the time dependence of ∆φ to differ for the two regimes. Behaviour of ∆φ(t) as well as the experimental setup and spectral fitting using the Python code will be discussed.Figure 1: a) Schematic depiction of the electronic electrostatic potential φ between a working (WE) and a reference electrode (RE). Electrostatic potential profile is not to scale. b) An example of the experimentally obtained time dependence of the C=O peak kinetic energy KE(t). KE(t) is related to φ(t) as ∆φ(t) = ∆KE(t).

Electrostatic Potentials Caused by the Release of Protons from Photoactivated Compound Sodium 2-Methoxy-5-nitrophenyl Sulfate at the Surface of Bilayer Lipid Membrane.

Lateral transport and release of protons at the water-membrane interface play crucial roles in cell bioenergetics. Therefore, versatile techniques need to be developed for investigating as well as clarifying the main features of these processes at the molecular level. Here, we experimentally measured the kinetics of binding of protons released from the photoactivated compound sodium 2-methoxy-5-nitrophenyl sulfate (MNPS) at the surface of a bilayer lipid membrane (BLM). We developed a theoretical model of this process describing the damage of MNPS coupled with the release of the protons at the membrane surface, as well as the exchange of MNPS molecules and protons between the membrane and solution. We found that the total change in the boundary potential difference across the membrane, ∆ϕb, is the sum of opposing effects of adsorption of MNPS anions and release of protons at the membrane-water interface. Steady-state change in the ∆ϕb due to protons decreased with the concentration of the buffer and increased with the pH of the solution. The change in the concentration of protons evaluated from measurements of ∆ϕb was close to that in the unstirred water layer near the BLM. This result, as well as rate constants of the proton exchange between the membrane and the bulk solution, indicated that the rate-limiting step of the proton surface to bulk release is the change in the concentration of protons in the unstirred layer. This means that the protons released from MNPS remain in equilibrium between the BLM surface and an adjacent water layer.

Diurnal Variations in Vegetation Activity affecting Shallow Groundwater Flow identified by Microthermal Measurements

Observations of summer microthermal temperature variations suggest, next to hydrological factors, a significant influence of plant activity on groundwater flow in fractured claystone materials. Variations in groundwater microtemperature were compared to variations in meteorological parameters and electrical potential of plants. With an increase in surface temperature, relative air humidity decreases and an increase in tree electrical potential, measured as the difference between the northern and the southern stem exposure (N–S), can be observed. This increase in electrical potential is concomitant with a change in groundwater temperature of approximately 2 mK. This relationship does not always occur. At high temperatures (+30°C) the decrease amounts to just 1 mK. This fact is related to the change in transpiration of plants, decreased or even suspended at high surface temperatures. A frequency analysis of all data showed a daily frequency of high magnitude in all parameters. Possibly changes in the macro weather situation events were observed in the results of atmospheric pressure, southern electric potential and groundwater temperature. The lag time between changes in electric potential and subsurface microtemperature changes amounts to 17 hours, possibly a result of the electrical potential difference between the northern and the southern exposure of the stem (N–S), and 5 hours, the result of the change in electrical potential difference between the southern and the northern stem exposure side (S–N). A comparison between potential changes and the computed change in gravity resulting from earth tidal effects showed that the correlation between the subsurface temperature variation with up to 2 mK and the change in surface temperature variation does not match directly. Other study shows that the impact of earth tides on subsurface microtemperature variation amounts to ca. 1mK. The effect of groundwater abstraction by mature vegetation is determined at the same range. Atmospheric tides can be correlated with the changes in north and south electric potentials.

Use of electric potential difference in audio magnetotelluric (AMT) geophysics for groundwater exploration

Due to recent advancements in technology, a variety of Audio Magnetotelluric (AMT) geophysical equipment using electric potential difference (V) as the main parameter for groundwater exploration is now in use. Studies on the application of electric potential difference in Audio Magnetotelluric Geophysics for groundwater exploration are yet to be published. This paper primarily provides an overview of the theoretical background on the use of the electric potential difference in Audio Magnetotelluric geophysics for groundwater exploration and shares recent field results from the application of the technology. In the field test, analysis of the lithology data collected during the drilling of two groundwater production boreholes provides meaning to the electric potential difference data collected prior to the drilling. Results show that the electric potential difference measured with the Audio Magnetotelluric Groundwater Detector correlated with lithology and groundwater occurrence at two observation sites. The water strikes occurred in sandstone formation of various degrees of disintegration and were associated with contrasts of low electric potential differences in the range of 0.005–0.019 mV. The finding suggests that the changes in electric potential difference can be used to delineate potential aquifers and vertical variation of geology. The expectations are that this presentation will stimulate further research to understand the applications of Audio Magnetotelluric electric potential difference technology for groundwater exploration in different hydrogeological settings.

Time-dependent measurement of plasmon-induced charge separation on a gold nanoparticle/TiO2 interface by electrostatic force microscopy

Plasmon-induced charge separation (PICS) is an efficient way to use the hot carriers generated by localized surface plasmon resonance. Although the ultrafast dynamics of hot carrier generation and annihilation itself are well understood, the slow dynamics of PICS are not, despite their importance for the use of hot carriers in chemical reactions. In this work, we directly observed the slow dynamics of PICS on an Au nanoparticle (NP)/TiO2 interface by using electrostatic force microscopy with time-resolved measurements obtained by sideband signal of frequency shift. The change in contact potential difference induced by PICS had a bias voltage dependence, indicating that the number of holes in the Au NPs ([{mathrm{h}}_{mathrm{AuNP}}^{+}]) accumulated by laser irradiation depended on bias voltage. The decay constant for the annihilation of the separated charge on the Au NPs at the Au NP/TiO2 interface was directly determined to be ca. 150 ms, and the annihilation process was discussed in a simple model based on the transient Schottky barrier.

Irradiation-induced corrosion tendencies evolution at the phase boundaries containing carbides in duplex stainless steel

Irradiation-assisted stress corrosion cracking normally initiates and propagates along grain/phase boundaries. Here, by using scanning Kelvin probe force microscopy, we characterized the Volta potential difference (VPD) changes prior and after proton irradiation at austenite/carbide (γ/C), ferrite/carbide (δ/C) and austenite/ferrite (γ/δ) interfaces in a 308 L stainless steel. It was found that, prior to irradiation, γ/C boundary had the lowest VPD, followed by δ/C and γ/δ. VPDs of all three types of phase boundaries slightly decreased after proton irradiation, wherein the γ/C boundary showed the largest VPD drop, followed by δ/C and γ/δ. The γ/C interface demonstrates the highest tendency of corrosion.

(Invited) Surface Photovoltage Spectroscopy on BiVO4, Gallium Phosphide, and CuGa3Se5 Photoelectrodes in Contact with Aqueous Electrolytes

The quasi-Fermi level splitting energy (photovoltage) is important for the solar to fuel conversion efficiency of photocatalysts and photoelectrodes. While electrochemical measurements can provide the electrochemical potential of the majority carriers at the semiconductor back-contact, the photovoltage, and the potential of the minority carriers at the front semiconductor/electrolyte are more difficult to determine experimentally, due to the lack of a direct electrical connection. Here we show that surface photovoltage spectroscopy (SPS) on photoelectrode films in contact with aqueous electrolytes can provide photovoltage information. For the measurements the semiconductor films (BiVO4, CuGa3Se5) or wafers (n-GaP or p-GaP) are immersed in aqueous electrolytes and placed underneath a vibrating Kelvin probe to monitor the light induced contact potential difference change. We find that the photovoltage (quasi-Fermi level splitting) of all photoelectrodes is increased by the aqueous electrolyte, and strongly depends on the electrochemical potential of the redox couple (TEOA, Na2SO3, KI, K4[Fe(CN)6] in the electrolyte, the back contact, and the light intensity. Electrochemical potentials of the minority carriers at the solid-liquid interface can be estimated by combining the photovoltage data with open circuit potential measurements that yield the quasi-Fermi levels of the majority carriers. This study provides new insight on the factors that affect photochemical charge separation at solid-liquid interfaces. Figure 1

Exciton Transfer at Heterointerfaces of MoS2 Monolayers and Fluorescent Molecular Aggregates.

Integration of distinct materials to form heterostructures enables the proposal of new functional devices based on emergent physical phenomena beyond the properties of the constituent materials. The optical responses and electrical transport characteristics of heterostructures depend on the charge and exciton transfer (CT and ET) at the interfaces, determined by the interfacial energy level alignment. In this work, heterostructures consisting of aggregates of fluorescent molecules (DY1) and 2D semiconductor MoS2 monolayers are fabricated. Photoluminescence spectra of DY1/MoS2 show quenching of the DY1 emission and enhancement of the MoS2 emission, indicating a strong electronic interaction between these two materials. Nanoscopic mappings of the light‐induced contact potential difference changes rule out the CT process at the interface. Using femtosecond transient absorption spectroscopy, the rapid interfacial ET process from DY1 aggregates to MoS2 and a fourfold extension of the exciton lifetime in MoS2 are elucidated. These results suggest that the integration of 2D inorganic semiconductors with fluorescent molecules can provide versatile approaches to engineer the physical characteristics of materials for both fundamental studies and novel optoelectronic device applications.

Electrical potentials of protoscoleces of the cestode Echinococcus granulosus from bovine origin

Larval stages of taeniid Echinococcus granulosus are the infective forms of cystic echinococcosis or hydatidosis, a worldwide zoonosis. The protoscolex that develops into the adult form in the definitive host is enveloped by a complex cellular syncytial tegument, where all metabolic interchange takes place. Little information is available as to the electrical activity of the parasite in this developmental stage. To gain insight into the electrical activity of the parasite at the larval stage, we conducted microelectrode impalements of bovine lung protoscoleces (PSCs) of Echinococcus granulosus in standard saline solution. We observed two distinct intra-parasitic potentials, a transient peak potential, and a stable second potential, most likely representing tegumental and intra-parasitic extracellular space electrical potential differences. These values changed on the developmental status of the parasite, its anatomical regions, or time course after harvesting. Changes in electrical potential differences of the parasite provide an accessible and valuable parameter for the study of transport mechanisms and potential targets for developing novel antiparasitic therapeutics.

Influence of gas adsorption on the surface photovoltage of Au nanorods embedded polymer coated ZnO nanorods under visible light irradiation

The synergism between the photosensitivity and gas sensitivity enabled the development of low powered highly selective gas sensors. In particular, organic/inorganic hybrid materials contribute to the coupling effect of light activated surface photovoltage modifications. In this report, the effect of visible light and volatile organic compounds (VOCs) on the hybrid sensing layer involving organic/inorganic/noble metal through scanning kelvin probe was disseminated. The sensor was fabricated by spin coating the layer-by-layer assembled poly (allylamine hydrochloride) (PAH) and dextran sulfate (DS) on hydrothermally grown ZnO nanorods followed by the incorporation of gold nanorods on ITO substrates. Structural and optical characterizations revealed the assembly of Au nanorods on the polymer coated ZnO nanorods and maximum absorbance in the visible light region, respectively. The optical nature of the hybrid sensor facilitated significant changes in contact potential difference (CPD) when irradiated with light. Changes in CPD values were measured with respect to alcohol, alkane and amine under illumination. A non-selective interaction was observed, yet the enhanced visible light response to triethylamine (TEA) corresponds to the formation of coordination bonds between the hybrid sensor and adsorbed species. The potential shift of ∼31 mV, ∼67 mV and ∼164 mV were observed for TEA by ZnO, ZnO/Poly and ZnO/Poly/Au, respectively. The simultaneous charge transfer/separation ability, surface plasmon resonance and inhibition of recombination of photogenerted carriers by Au promoted the interaction. Evidence of selective interaction can be elucidated through the selection of different VOCs under specific type of gas for CPD measurements.