ElectrocatalysisPub Date : 2023-04-01DOI: 10.1007/s12678-023-00819-w
Guobing Wei, Qiqi Fan, Nian Hong, Hanfeng Cui, Wenxing Zhang, Mijit Rustam, Alxir Alim, Tao Jiang, Huanhuan Dong, Hao Fan
{"title":"A Reagentless Aptamer Sensor Based on a Self-Powered DNA Machine for Electrochemical Detection of AFB1","authors":"Guobing Wei, Qiqi Fan, Nian Hong, Hanfeng Cui, Wenxing Zhang, Mijit Rustam, Alxir Alim, Tao Jiang, Huanhuan Dong, Hao Fan","doi":"10.1007/s12678-023-00819-w","DOIUrl":"10.1007/s12678-023-00819-w","url":null,"abstract":"<p>A reagentless electrochemical aptamer sensor for AFB1 detection was constructed based on DNAzyme-driven DNA walker and bisferrocene. No significant change in electrochemical signal was observed when the target AFB1 was not added. The electrochemical signal was significantly reduced when the target AFB1 was added.</p>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"14 4","pages":"593 - 601"},"PeriodicalIF":3.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4001407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ElectrocatalysisPub Date : 2023-03-16DOI: 10.1007/s12678-023-00820-3
Muhammad Nurdin, Ilham Ilham, Maulidiyah Maulidiyah, Muh. Zakir Muzakkar, Dwiprayogo Wibowo, Zul Arham, La Ode Agus Salim, Irwan Irwan, Catherina Bijang, Akrajas Ali Umar
{"title":"Enhanced Photoelectrocatalytic Performance Using Chalcogenide Te/TiO2/Ti Nanotube Array Based on COD Analyses for Water Treatment Applications","authors":"Muhammad Nurdin, Ilham Ilham, Maulidiyah Maulidiyah, Muh. Zakir Muzakkar, Dwiprayogo Wibowo, Zul Arham, La Ode Agus Salim, Irwan Irwan, Catherina Bijang, Akrajas Ali Umar","doi":"10.1007/s12678-023-00820-3","DOIUrl":"10.1007/s12678-023-00820-3","url":null,"abstract":"<div><p>The effect of Te doping of the TiO<sub>2</sub>/Ti nanotube arrays (NTAs) on the photoelectrochemical chemical oxygen demand (COD) detection has been investigated. It is found that the Te doping has enhanced the photoelectrocatalytic properties of the TiO<sub>2</sub>/Ti NTAs electrode. This indicated by the linearity, accuracy, and repeatability of measurement of the test compounds chemicals. The Te-TiO<sub>2</sub>/Ti NTAs shows an excellent linearity to all test compounds up to 10 μM of concentration. It is only up to 5 μM in pristine TiO<sub>2</sub>/Ti NTAs system. In term of accuracy, the Te-TiO<sub>2</sub>/Ti NTAs electrode can provide the measurement accuracy of up to 100% fit to the theoretical value for all test compound chemical. It is only less than 80% for TiO<sub>2</sub>/Ti NTAs electrode. Meanwhile, the repeatability of measurement for the electrode, the Te-TiO<sub>2</sub>/Ti NTAs exhibits 1.8% RSD value, which is lower than the pristine TiO<sub>2</sub>/Ti NTAs, i.e., 2%. The enhancement of the photoelectrocatalytic properties of the TiO<sub>2</sub> by Te doping is due to the lowering of electron and hole recombination during the photoactivation, promoting massive surface reaction with organic compounds and improving the sensing sensitivity. The Te-TiO<sub>2</sub>/Ti NTAs should find the extensive application of PECOD detection of organic contamination in the environment.</p></div>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"14 4","pages":"581 - 592"},"PeriodicalIF":3.1,"publicationDate":"2023-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12678-023-00820-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4655430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ElectrocatalysisPub Date : 2023-03-10DOI: 10.1007/s12678-023-00817-y
João Paulo Tenório da Silva Santos, Sherlan Guimarães Lemos, Murilo Fernando Gromboni, Vinicius Del Colle, Artur José Santos Mascarenhas, Valéria Cristina Fernandes
{"title":"Chemometric Investigation of Platinum Electrodeposition on Titanium Substrates for Ethanol Electro-oxidation","authors":"João Paulo Tenório da Silva Santos, Sherlan Guimarães Lemos, Murilo Fernando Gromboni, Vinicius Del Colle, Artur José Santos Mascarenhas, Valéria Cristina Fernandes","doi":"10.1007/s12678-023-00817-y","DOIUrl":"10.1007/s12678-023-00817-y","url":null,"abstract":"<div><p>The objective of this work is to employ chemometric tools to investigate the influence of the synthesis parameters in platinum electrodeposition on a titanium substrate using cyclic voltammetry. Through a 2<sup>2</sup> factorial design, using as response the maximum peak current density during the ethanol electro-oxidation, one can observe that the number of cycles and the scan rate are both significant, but the interaction between them is not. The maximum peak current density is observed for the electrode obtained with NC = 20 cycles and SR = 200 mV s<sup>−1</sup>. The structural characterization indicates that the surface irregularity of the substrate causes an uneven growth of the (200) and (220) crystallographic planes, which present different performances in the electro-oxidation of ethanol. The response surface methodology indicates that the best experimental condition is that obtained with 10 cycles and 218 mV s<sup>−1</sup>. The Pt/Ti electrodes prepared with the optimized parameters are promising.\u0000</p><h3>Graphical Abstract</h3>\u0000 <figure><div><div><div><picture><source><img></source></picture></div></div></div></figure>\u0000 <p>A 2<sup>2</sup> factorial design was applied to prepare Pt/Ti for ethanol eletro-oxidation. Pt electrodeposits have shown an atypical “house of cards” morphology. Preferential orientation of Pt on Ti surface are related to better activity. Response surface methodology points 10 cycles at 218 mV s<sup>−1</sup> as the best condition.</p></div>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"14 4","pages":"570 - 580"},"PeriodicalIF":3.1,"publicationDate":"2023-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4430867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ElectrocatalysisPub Date : 2023-03-04DOI: 10.1007/s12678-023-00816-z
Vanessa L. Oliveira, Yvonne Soldo-Olivier, Edson A. Ticianelli, Marian Chatenet, Eric Sibert
{"title":"Formic Acid Electrooxidation on Palladium Nano-Layers Deposited onto Pt(111): Investigation of the Substrate Effect","authors":"Vanessa L. Oliveira, Yvonne Soldo-Olivier, Edson A. Ticianelli, Marian Chatenet, Eric Sibert","doi":"10.1007/s12678-023-00816-z","DOIUrl":"10.1007/s12678-023-00816-z","url":null,"abstract":"<div><p>The influence of Pd nano-layers electro-deposited onto Pt(111) single crystal has been systematically studied toward the formic acid electrochemical oxidation reaction in H<sub>2</sub>SO<sub>4</sub> and HClO<sub>4</sub>. The studied Pd<sub>xML</sub>/Pt(111) surfaces (<i>x</i> = 1, 2, 5, and 16 monolayers (ML)) are all more active than Pt(111) toward formic acid oxidation, even if the activity is very sensitive to the Pd film thickness and morphology. In sulfate solution, the competitive adsorption of long-range ordered (bi)sulfate on the pseudomorphic Pd terraces effectively hinders the formic acid oxidation only on the thinnest films. We could observe the different roles of the (bi)sulfate adsorption on the first and on the following deposited Pd layers. The sulfate adsorption competitive role rapidly fades away beyond about 5 ML of equivalent thickness, due to the surface roughness increasing and terraces width diminishing. In perchlorate media, anions do not adsorb competitively with formic acid intermediates, allowing a larger activity of the formic acid oxidation up to about 5 ML. At higher thicknesses, the difference in activity between the two electrolytic media is reduced, and it drops in both electrolytes close to 0.5 V vs. RHE, where Pd surface oxides are formed. Coupling the electrochemical results with the Pd layer structural description previously obtained from in situ SXRD experiments, the outstanding activity of Pd<sub>1ML</sub>/Pt(111) observed in perchloric solution can be explained by the ligand effect of the underlying platinum atoms on the first pseudomorphic Pd layer. This advantageous effect is lost for Pd deposits thicker than 1 ML.</p><h3>Graphical Abstract</h3>\u0000 <figure><div><div><div><picture><source><img></source></picture></div></div></div></figure>\u0000 </div>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"14 4","pages":"561 - 569"},"PeriodicalIF":3.1,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12678-023-00816-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4174076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ElectrocatalysisPub Date : 2023-03-04DOI: 10.1007/s12678-023-00818-x
S. Amira, M. Ferkhi, F. Mauvy, S. Fourcade, J. M. Bassat, J. C. Grenier
{"title":"La1.5Nd0.3Pr0.2NiO4.16: A New Cathode Material for IT-Solid Oxide Fuel Cells","authors":"S. Amira, M. Ferkhi, F. Mauvy, S. Fourcade, J. M. Bassat, J. C. Grenier","doi":"10.1007/s12678-023-00818-x","DOIUrl":"10.1007/s12678-023-00818-x","url":null,"abstract":"<div><p>The La<sub>1.5</sub>Nd<sub>0.3</sub>Pr<sub>0.2</sub>NiO<sub>4.16</sub> material was prepared by the citrate method and used as a cathode for a solid oxide fuel cell (SOFC). The study was carried out in the presence of a thin interfacial layer composed of 50% GDC10 and 50% 8YSZ deposited on both surfaces of the GDC10 (Ce<sub>1.9</sub>Gd<sub>0.1</sub>O<sub>1.95</sub>) electrolyte. The purity of the materials was studied by X-ray diffraction, while X-ray photon-electron spectrometry (XPS) was used to characterize the surface chemical state of the synthesized material; the morphology of the electrode and cross-sectional images of the cell were obtained by scanning electron microscopy (SEM). Iodometric titration has also been performed to evaluate oxygen over-stoichiometry. Cross-sectional SEM images have shown good adherence between all the cell components, and the cationic character of the cathode material was confirmed by the XPS and iodometric analysis. The use of these materials as an oxygen cathode has shown interesting electrochemical properties with an area-specific resistance (ASR) value of the order of 0.060 (Ω.cm<sup>2</sup>) at 600 °C and 0.022 (Ω.cm<sup>2</sup>) at 700 °C. The activation energy (Ea) of the LNPNO5 material is very low and is of the order of 0.96 eV.</p><h3>Graphical Abstract</h3>\u0000 <figure><div><div><div><picture><source><img></source></picture></div><div><p>1. An anionic character of La<sub>1.5</sub>Nd<sub>0.3</sub>Pr<sub>0.2</sub>NiO<sub>4.16</sub> was determined; an important property for easy displacement of oxide ions in these materials.</p><p>2. At 600 and 700 °C, the ASRs of La<sub>1.5</sub>Nd<sub>0.3</sub>Pr<sub>0.2</sub>NiO<sub>4.16</sub> were as low as 0.06 Ω.cm<sup>2</sup> and 0.022 Ω.cm<sup>2</sup>, respectively.</p><p>3. The presence of the new interfacial layer (8YSZ (50%) + GDC10 (50%) is of interest to operate at intermediate temperatures for SOFCs.</p><p>4. La<sub>1.5</sub>Nd<sub>0.3</sub>Pr<sub>0.2</sub>NiO<sub>4.16</sub> can be qualified to be an excellent cathode material for SOFC fuel cells operating at intermediate temperatures, 600 – 700 °C.</p></div></div></div></figure>\u0000 </div>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"14 4","pages":"546 - 560"},"PeriodicalIF":3.1,"publicationDate":"2023-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4511578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ElectrocatalysisPub Date : 2023-02-16DOI: 10.1007/s12678-023-00812-3
Fozia, Guangyao Zhao, Yanhong Nie, Jianrong Jiang, Qian Chen, Chaogang Wang, Xu Xu, Ming Ying, Zhangli Hu, Hong Xu
{"title":"Preparation of Nitrate Bilayer Membrane Ion-Selective Electrode Modified by Pericarpium Granati-Derived Biochar and Its Application in Practical Samples","authors":"Fozia, Guangyao Zhao, Yanhong Nie, Jianrong Jiang, Qian Chen, Chaogang Wang, Xu Xu, Ming Ying, Zhangli Hu, Hong Xu","doi":"10.1007/s12678-023-00812-3","DOIUrl":"10.1007/s12678-023-00812-3","url":null,"abstract":"<div><h2>Abstract\u0000</h2><div><p>In this study, a <i>pericarpium granati</i>-derived biochar with phosphoric acid activation (PGCP) was prepared, characterized, and applied together with polypyrrole (PPy) to modify a glass carbon electrode (GCE) to construct a bilayer membrane nitrate ion-selective electrode (ISE, PPy/PGCP/GCE). The morphological results showed that PGCP possessed a porous structures. X-ray photoelectron spectroscopy analysis indicated that phosphorus added in PGCP was in the forms of P-O and P–C. The electrochemical impedance spectrum of the fabricated nitrate ISE showed a very low impedance, suggesting that PGCP can be used as an effective electron transfer mediator. The open circuit potential experiments indicated that the fabricated nitrate ISE exhibited a good linear potentiometric response to nitrate over a wide concentration range of 1 × 10<sup>−5</sup> to 5 × 10<sup>−1</sup> mol·L<sup>−1</sup> with Nernstian slope of 50.86 mV·dec<sup>−1</sup> at pH range of 3.5–9.5 and a short response time of less than 7.3 s. Its limit of detection (LOD) was determined to be 4.64 × 10<sup>−6</sup> mol·L<sup>−1</sup>. Both detection range and LOD are comparable or better than those of reported similar modified electrodes. The fabricated nitrate ISE exhibited a high selectivity with a good repeatability and stability. The selectivity sequence was determined as NO<sub>3</sub><sup>−</sup> > NO<sub>2</sub><sup>−</sup> > Cl<sup>−</sup> > H<sub>2</sub>PO<sub>4</sub><sup>−</sup> > CH<sub>3</sub>COO<sup>−</sup> > CO<sub>3</sub><sup>2−</sup> > SO<sub>4</sub><sup>2−</sup>. The fabricated nitrate ISE was validated by the nitrate detections of real samples from Shenzhen OCT wetland and laboratory wastewater, respectively, with the obtained detection discrepancy of less than 4% (RSD). This study provides useful reference information for the development of novel ISE in clinical laboratories and environmental monitoring.</p></div></div>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"14 4","pages":"534 - 545"},"PeriodicalIF":3.1,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12678-023-00812-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4934489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Measurement of Ionomer Coverage on Carbon and Pt in Catalyst Layer of Polymer Electrolyte Fuel Cells by Electrochemical Impedance Spectroscopy","authors":"Saori Minami, Shuji Kajiya, Haruhiko Yamada, Kazuma Shinozaki, Ryosuke Jinnouchi","doi":"10.1007/s12678-023-00809-y","DOIUrl":"10.1007/s12678-023-00809-y","url":null,"abstract":"<div><p>Surface coverages of ionomer on Pt and carbon support are key properties to clarify the ionomer distribution in cathode catalyst layer of polymer electrolyte fuel cells. However, their measurement is highly challenging especially for carbon, where Faradaic charge is not visible in voltammograms. Conventionally, the capacitance measured by voltammetry or electrochemical impedance spectroscopy is used to determine the ionomer coverage. In these methods, surface coverages are obtained by comparing the double layer capacitance at wet condition with that at dry condition; Pt and carbon surfaces covered by ionomer and water contributes to the capacitance at wet condition, while surfaces covered only by the ionomer contributes at the dry condition because of the absence of water. However, when measured capacitance is converted to surface area, the methods assume that the specific capacitance (capacitance per surface area) is independent of the humidity although it significantly changes in reality, because the double layer structure of ionomer changes. Here, we propose an alternative method that significantly suppresses the change in specific capacitance. The method was applied to porous and nonporous carbon supports with Pt nanoparticle catalyst. The measurement also indicates that the surface coverages on both Pt and carbon are reduced in the case of the porous carbon.</p><h3>Graphical Abstract</h3>\u0000 <figure><div><div><div><picture><source><img></source></picture></div></div></div></figure>\u0000 </div>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"14 4","pages":"522 - 533"},"PeriodicalIF":3.1,"publicationDate":"2023-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4567176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ElectrocatalysisPub Date : 2023-02-13DOI: 10.1007/s12678-023-00814-1
Madhurima Barman, Venkata Sai Sriram Mosali, Alan M. Bond, Jie Zhang, A. Sarkar
{"title":"Multi-products (C1 and C2) Formation from Electrochemical Reduction of Carbon Dioxide Catalyzed by Oxide-Derived Coppers Prepared Using Varied Synthesis Conditions","authors":"Madhurima Barman, Venkata Sai Sriram Mosali, Alan M. Bond, Jie Zhang, A. Sarkar","doi":"10.1007/s12678-023-00814-1","DOIUrl":"10.1007/s12678-023-00814-1","url":null,"abstract":"<div><p>In order to explore the effects of morphology, specific surface area and relative content of Cu/Cu-oxide in “CuO-derived Cu” electrocatalysts on the current density and product formation during electrochemical carbon dioxide reduction reaction (eCO<sub>2</sub>RR), CuO electrocatalysts were synthesized via solution combustion and hydrothermal routes, possessing different morphologies. The as-synthesized CuOs were first reduced to Cu at − 0.8 V (vs. RHE), till the currents got stabilized; thus, forming “CuO-derived Cu”. Subsequently, eCO<sub>2</sub>RR was carried out via bulk electrolysis at different potentials between − 0.6 and − 1.6 V (using 0.1 M KHCO<sub>3</sub> solution), leading to the formation of seven liquid/gaseous products, viz., CO, methane, ethylene, formate, acetate, and ethanol (in addition to H<sub>2</sub>). It was interesting to note that the type of products and associated faradic efficiencies (FEs) were governed by the Cu-content of the “CuO-derived Cu” electrocatalysts (i.e., Cu:CuO ratio), as obtained post the pre-reduction step and looked into here as one of the starting conditions of the electrocatalysts. Higher initial Cu-content of the pre-reduced CuOs resulted in higher FEs at lower negative potentials. Furthermore, high Cu-content (even for simple equiaxed morphology), as opposed to any special morphology (say, rod/whisker-type), has been found to be particularly important for the formations of methane and formate; yielding a maximum FE of ~ 18.6 ± 1.2% at − 1.0 V for the latter. Accordingly, the present work reveals the relative roles of specific surface area and Cu/CuO-content of “CuO-derived Cu” electrocatalysts on the current densities, product formation and associated FEs on eCO<sub>2</sub>RR.</p><h3>Graphical Abstract</h3>\u0000 <figure><div><div><div><picture><source><img></source></picture></div></div></div></figure>\u0000 </div>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"14 4","pages":"511 - 521"},"PeriodicalIF":3.1,"publicationDate":"2023-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4536404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Investigation of Charge–Discharging Behavior of Metal Oxide–Based Anode Electrocatalysts for Alkaline Water Electrolysis to Suppress Degradation due to Reverse Current","authors":"Kazuaki Oda, Yoshiyuki Kuroda, Shigenori Mitsushima","doi":"10.1007/s12678-023-00815-0","DOIUrl":"10.1007/s12678-023-00815-0","url":null,"abstract":"<div><p>In the bipolar-type alkaline water electrolysis powered by renewable energy, electrocatalysts are degraded by repeated potential change associated with the generation of reverse current. If an electrode has large discharge capacity, the opposite electrode on the same bipolar plate is degraded by the reverse current. In this study, discharge capacity of various transition metal-based electrocatalysts was investigated to clarify the determining factors of electrocatalysts on the reverse current and durability. The discharge capacities from 1.5 to 0.5 V vs. RHE (<i>Q</i><sub>dc,0.5</sub>) of electrocatalysts are proportional to the surface area in most cases. The proportionality coefficient, corresponding to the specific capacity, is 1.0 C·m<sup>–2</sup> for Co<sub>3</sub>O<sub>4</sub> and 2.3 C·m<sup>–2</sup> for manganese-based electrocatalysts. The substitution of Co<sup>3+</sup> in Co<sub>3</sub>O<sub>4</sub> with Ni<sup>3+</sup> increased<i> Q</i><sub>dc,0.5</sub>. The upper limit of theoretical specific capacity for Co<sub>3</sub>O<sub>4</sub> is estimated to be 1.699 C·m<sup>–2</sup>, meaning the former and latter cases correspond to 2- and 1-electron reactions, respectively, per a cation at the surface. The discharge capacities of the elctrocatalysts increased because of the dissolution and recrystallization of nickel and/or cobalt into metal hydroxides. The increase in the capacities of Co<sub>3</sub>O<sub>4</sub> and NiCo<sub>2</sub>O<sub>4</sub> during ten charge–discharge cycles was below 2–9% and 0.5–38%, respectively. Therefore, if a cathode electrocatalyst with relatively low redox durability is used on the one side of a bipolar plate, it is necessary to control optimum discharge capacity of the anode by changing surface area and constituent metal cations to minimize the generation of reverse current.</p><h3>Graphical Abstract</h3>\u0000 <figure><div><div><div><picture><source><img></source></picture></div></div></div></figure>\u0000 </div>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"14 3","pages":"499 - 510"},"PeriodicalIF":3.1,"publicationDate":"2023-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12678-023-00815-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4417656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ElectrocatalysisPub Date : 2023-02-06DOI: 10.1007/s12678-023-00813-2
Behjat Deiminiat, Gholam Hossein Rounaghi
{"title":"Fabrication of a Novel Photoelectrochemical Aptasensor Using Gold Nanoparticle-Sensitized TiO2 Film for Quantitative Determination of Diazinon in Solutions","authors":"Behjat Deiminiat, Gholam Hossein Rounaghi","doi":"10.1007/s12678-023-00813-2","DOIUrl":"10.1007/s12678-023-00813-2","url":null,"abstract":"<div><p>This paper reports the development of a simple and new photoelectrochemical (PEC) aptamer-based sensor for ultrasensitive determination of the concentration of diazinon (DZN) using the surface plasmon resonance effect (SPR) of gold nanoparticles (AuNPs) deposited on a titanium dioxide (TiO<sub>2</sub>) film. A thin layer of flourin tin-oxide (FTO) was covered on the surface of glass plates during the spray pyrolysis process, and the resulting FTO plates were modified layer by layer with TiO<sub>2</sub> film and AuNPs as the photoactive nanomaterials. The AuNPs were utilized to increase the absorption rate of visible light through the formation of hot electrons. The prepared AuNPs/TiO<sub>2</sub> nanocomposite revealed a higher photoelectro catalytic activity compared to the pure TiO<sub>2</sub>. In order to improve the selectivity of the proposed PEC sensor, the thiolated aptamer was conjugated to the AuNPs/TiO<sub>2</sub> nanocomposite through S–Au bonds. Upon exposition of the fabricated PEC apatasensor to DZN molecules, the formation of the aptamer-DZN complex restricted the electron transfer at the surface of the PEC sensor; therefore, the photocurrent signal decreased. The simultaneous usage of the PEC technique and aptamer led to the improvement of the analytical performance of the proposed sensor in terms of sensitivity, selectivity, reproducibility, and stability for the quantitative determination of diazinon with a wide linear range of 0.2 to 1000 nM and a low detection limit of 0.04 nM. In addition, the prepared PEC aptasensor was used for the determination of diazinon in water and biological samples, and satisfactory results were obtained which confirms the practical application of the proposed PEC aptasensor.</p></div>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"14 3","pages":"484 - 498"},"PeriodicalIF":3.1,"publicationDate":"2023-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4248796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}