Ethanol solution sensor based on ZnO/PSi nanostructures synthesized by catalytic immersion method at different molar ratio concentrations: An electrochemical impedance analysis

Electrochemical impedance spectroscopy (EIS): An efficiency method to monitor resin curing processes

“…Curing degree determined by DSC as respect to curing time can be estimated using Eq. (7), and the curves of curing degree with respect to curing time are presented in Fig. 6.…”

“…EIS, as an sensitive tool to for investigating electrochemical systems, has the advantage of separating interfacial processes at different frequency domain, and it is useful to analyze the reaction mechanism of the electrode system [1][2][3][4]. Its applications are close related to sensors, catalysts, solar cells, supercapacitors, corrosion science, etc [5][6][7][8][9]. Analysis of EIS spectra with equivalent electrical circuits (EEC) can help quantify the various contributions to the overall impedance, such as charge transfer resistance, solution resistance, double layer capacitance and so on.…”

Nanosilicon-Based Composites for (Bio)sensing Applications: Current Status, Advantages, and Perspectives

“…), which play a crucial role for the effective detection of (bio)molecules. Mainly, MOx nanolayers/nanoparticles can be deposited over a nano-Si surface through the following techniques: (i) RF and DC magnetron sputtering [24,34,36,37,120,121,123,124,125,126]; (ii) sol–gel/hydrothermal synthesis + spin coating [17,26,127,128,129,130,131]; (iii) drop casting technique + pulsed laser ablation in liquid [132]; (iv) vapor–liquid–solid growth and chemical vapor deposition [25,40,133]; (v) catalytic immersion method [134]; and (vi) electrochemical and chemical deposition [35,122,135].…”

“…A number of works have also been published on the p-n heterojunction by using a combination of p-type PSi and n-type ZnO [24,35,36,122,125,134], WO 3 [36,129,137,138,139], SnO 2 [122,133], V 2 O 5 [37], and TiO 2 [120]. The sensitivity of these nanocomposites was enhanced in comparison to the bare semiconductors and this can be explained as follows [120]: (a) a reduction in the surface activation energy E a upon the formation of the p-n heterojunction, resulting in increased analyte adsorption; (b) the presence of oxygen species and dangling bonds on PSi/MOx, and as a consequence, more reaction sites on the surface, which improved the adsorption of target molecules.…”

“…It should be noted that tuning the scale of the MOx nanolayer or nanoparticles and the morphology of the Si surface are very important elements for sensor design. Husairi et al showed that the PSi/ZnO sensor response to ethanol depends on the concentration and type of defects and area of active sites for absorption as the number of defects and active species on the PSi/ZnO surface was directly affected by the precursor (Zn(NO 3 ) 2 6H 2 O) concentration [134]. In [122,125], ZnO nanolayers were deposited over PSi and c-Si by using zinc acetate (ZA) and carbonate (ZC) precursors via chemical bath deposition (CBD) and the magnetron-sputtering technique, respectively.…”