Xiaolong Liu, Guangying Fu, Qiaolin Lang, Ruiqin Ding, Qiangsheng Guo, Ke Liang, Shuman Gao, Xiaobo Yang and Bing Yu
{"title":"Reaction intermediates recognized by in situ FTIR spectroscopy in CO2 hydrogenation over the Cu/ZnO/SPP-zeolite catalyst†","authors":"Xiaolong Liu, Guangying Fu, Qiaolin Lang, Ruiqin Ding, Qiangsheng Guo, Ke Liang, Shuman Gao, Xiaobo Yang and Bing Yu","doi":"10.1039/D4LF00266K","DOIUrl":"https://doi.org/10.1039/D4LF00266K","url":null,"abstract":"<p >Cu/ZnO nanoparticles embedded in zeolites possess smaller particle sizes than those in the conventional Cu/ZnO/Al<small><sub>2</sub></small>O<small><sub>3</sub></small> catalyst. Therefore, they exhibit a distinctive manner of interaction with the reactants in the catalytic hydrogenation of CO<small><sub>2</sub></small> to methanol. The present paper uses <em>in situ</em> FTIR spectroscopy to recognize the introduction and removal of various carbonates, carbonyl, formates and water species adsorbed on the surface of a Cu/ZnO/SPP-zeolite catalyst in reactive flows. Together with other characterization results, such as <em>quasi-in situ</em> XPS, it was revealed that the Cu surfaces have an uneven electronic distribution and that constant carbonate coverage, low water adsorption, and fast consumption of carbonyls and formates are associated with the high conversion frequency of CO<small><sub>2</sub></small> over the Cu/ZnO/zeolite material.</p>","PeriodicalId":101138,"journal":{"name":"RSC Applied Interfaces","volume":" 1","pages":" 114-121"},"PeriodicalIF":0.0,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/lf/d4lf00266k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Masood Ali, Yanling Yang, Ayyah Abdoh and Yousuf Mohammed
{"title":"Topographical characteristics of 3D printed polymeric microneedle surface and its impact on coating formulation attributes","authors":"Masood Ali, Yanling Yang, Ayyah Abdoh and Yousuf Mohammed","doi":"10.1039/D4LF00177J","DOIUrl":"https://doi.org/10.1039/D4LF00177J","url":null,"abstract":"<p >In recent years, 3D printing has emerged as a promising technique for fabricating polymeric microneedles (μNDs), offering flexibility and precision. However, the surface topography of these μNDs plays a pivotal role in determining coating formulation characteristics and, consequently, their efficacy in drug delivery applications. This review delves into contemporary approaches for evaluating the surface topography of 3D printed polymeric μNDs, exploring its impact on coating formulation characteristics. With reference to the latest research in the materials industry, we elucidate the close relationship between the adhesion of coating material and μND surface, considering their physical and chemical properties. Fundamental principles relevant to understanding the influence of surface topography on therapeutic coating are discussed, emphasising how surface microtopography influences adhesion strength. Moreover, non-contact methodologies such as profilometry are reviewed for characterising μND surface morphology, highlighting their utility in assessing surface roughness, porosity, and feature geometry. Additionally, we explore how coating formulation attributes dictate surface wetting, surface energy, and interfacial adhesion strength. Insights from this review offer valuable guidance for optimising the fabrication process of 3D printed polymeric μNDs, tailoring their surface topography to enhance coating formulation performance in diverse biomedical applications.</p>","PeriodicalId":101138,"journal":{"name":"RSC Applied Interfaces","volume":" 6","pages":" 1108-1128"},"PeriodicalIF":0.0,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lf/d4lf00177j?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anna C. Kundmann, Kathleen Becker and Frank E. Osterloh
{"title":"Surface photovoltage predicts open circuit voltage in GaP/PEDOT:PSS and GaP/CuSCN heterojunction solar cells†","authors":"Anna C. Kundmann, Kathleen Becker and Frank E. Osterloh","doi":"10.1039/D4LF00225C","DOIUrl":"https://doi.org/10.1039/D4LF00225C","url":null,"abstract":"<p >The cost-effective fabrication of inorganic photovoltaic (PV) devices is important for their implementation on a global scale. Solution processing techniques, such as spray coating, spin coating, and electrodeposition, can drive down costs; however, a better understanding of the charge transfer characteristics of the resulting semiconductor heterojunctions is needed to minimize photovoltage losses at interfaces. In this work, we generate solution-processed heterojunctions by spin coating PEDOT:PSS and electrodepositing CuSCN as hole transport layers (HTLs) onto GaP wafers. After adding silver paint as a front contact, we obtain devices with short circuit current densities of 0.40 mA cm<small><sup>−2</sup></small> and 0.18 mA cm<small><sup>−2</sup></small>, open circuit voltages of 0.47 V and 0.43 V, and power conversion efficiencies of 0.045% and 0.031% for PEDOT:PSS and CuSCN HTLs, respectively. Surface photovoltage spectroscopy (SPS) is used to study photochemical charge separation at the illuminated GaP interfaces. We find that the surface photovoltage signal is a good predictor of the photovoltage of the devices, as confirmed by comparison with open circuit potential data. SPS also reveals improved hole collection by the HTLs and a detrimental Schottky junction at the In/GaP back contact, further evidenced by S-shaped current–voltage profiles in electric measurements. Reducing the Schottky barrier height will be essential to improve device performance.</p>","PeriodicalId":101138,"journal":{"name":"RSC Applied Interfaces","volume":" 6","pages":" 1426-1435"},"PeriodicalIF":0.0,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lf/d4lf00225c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Leon Leuppert, Adam Reupert, Thomas Diemant, Tom Philipp, Christine Kranz, Zhenyou Li and Maximilian Fichtner
{"title":"Electrolyte-dependent deposition morphology on magnesium metal utilizing MeMgCl, Mg[B(hfip)4]2 and Mg(HMDS)2–2AlCl3 electrolytes†","authors":"Leon Leuppert, Adam Reupert, Thomas Diemant, Tom Philipp, Christine Kranz, Zhenyou Li and Maximilian Fichtner","doi":"10.1039/D4LF00124A","DOIUrl":"https://doi.org/10.1039/D4LF00124A","url":null,"abstract":"<p >The deposition behavior of two state-of-the-art electrolytes, magnesium tetrakis(hexafluoroisopropyloxy)borate (Mg[B(hfip)<small><sub>4</sub></small>]<small><sub>2</sub></small>) in dimethoxyethane (DME) and magnesium bis(hexamethyldisilazide) with two equivalents of aluminum chloride (Mg(HMDS)<small><sub>2</sub></small>–2AlCl<small><sub>3</sub></small>) in tetrahydrofuran (THF) was investigated. Using symmetric flooded magnesium–magnesium cells with different electrolyte concentrations and current densities the deposition process was monitored optically <em>in situ</em> by a video microscope. The deposits were also investigated by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) spectroscopy and compared to deposition from methylmagnesium chloride (MeMgCl) in THF, known for its dendritic growth. Furthermore, the chemical composition of the surfaces after deposition was tested by X-ray photoelectron spectroscopy (XPS). In this work, MeMgCl showed unidirectional growth and for the harshest applied conditions, mossy deposition, but no branching dendrites as previously reported in the literature. Mg[B(hfip)<small><sub>4</sub></small>]<small><sub>2</sub></small> and Mg(HMDS)<small><sub>2</sub></small>–2AlCl<small><sub>3</sub></small> did not show the formation of dendrites or a dendrite preform but also did not result in the desired smooth layer but in spherical deposits. For the Mg[B(hfip)<small><sub>4</sub></small>]<small><sub>2</sub></small> electrolyte, the influence of magnesium borohydride (Mg(BH<small><sub>4</sub></small>)<small><sub>2</sub></small>) as an additive was additionally tested, resulting in a more planar growth.</p>","PeriodicalId":101138,"journal":{"name":"RSC Applied Interfaces","volume":" 6","pages":" 1142-1155"},"PeriodicalIF":0.0,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lf/d4lf00124a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tomoya Otono, Hamdi Ben Yahia, Chie Hotehama, Kota Motohashi, Atsushi Sakuda and Akitoshi Hayashi
{"title":"Preparation and characterization of new solid electrolytes Na3−xZn1−xAl1+xS4†","authors":"Tomoya Otono, Hamdi Ben Yahia, Chie Hotehama, Kota Motohashi, Atsushi Sakuda and Akitoshi Hayashi","doi":"10.1039/D4LF00275J","DOIUrl":"https://doi.org/10.1039/D4LF00275J","url":null,"abstract":"<p >Sulfide solid electrolytes, known for their high ionic conductivity and formability, are key materials for the practical use of all-solid-state sodium batteries. In this study, new sulfide solid electrolyte materials, Na<small><sub>3−<em>x</em></sub></small>Zn<small><sub>1−<em>x</em></sub></small>Al<small><sub>1+<em>x</em></sub></small>S<small><sub>4</sub></small> (<em>x</em> ≤ 0.2), were prepared <em>via</em> a self flux synthesis route, using reagents such as Na<small><sub>2</sub></small>S, Zn, Al, and S. The new materials were characterized using X-ray powder diffraction, Raman spectroscopy, and electrochemical impedance spectroscopy. Na<small><sub>3−<em>x</em></sub></small>Zn<small><sub>1−<em>x</em></sub></small>Al<small><sub>1+<em>x</em></sub></small>S<small><sub>4</sub></small> formed a solid solution up to <em>x</em> = 0.2 and crystallized with a β-Ca<small><sub>3</sub></small>Ga<small><sub>2</sub></small>N<small><sub>4</sub></small>-type structure. As the Al content increased, the number of sodium vacancies also increased, resulting in improved ionic conductivity. Among Na<small><sub>3−<em>x</em></sub></small>Zn<small><sub>1−<em>x</em></sub></small>Al<small><sub>1+<em>x</em></sub></small>S<small><sub>4</sub></small> samples, Na<small><sub>2.9</sub></small>Zn<small><sub>0.9</sub></small>Al<small><sub>1.1</sub></small>S<small><sub>4</sub></small> exhibited the highest ionic conductivity of 4.5 × 10<small><sup>−6</sup></small> S cm<small><sup>−1</sup></small> at 25 °C and lowest activation energy of 32 kJ mol<small><sup>−1</sup></small>. Furthermore, the Na<small><sub>2.9</sub></small>Zn<small><sub>0.9</sub></small>Al<small><sub>1.1</sub></small>S<small><sub>4</sub></small> phase was relatively stable when exposed to humid air, which facilitated its practical use in all-solid-state sodium batteries.</p>","PeriodicalId":101138,"journal":{"name":"RSC Applied Interfaces","volume":" 6","pages":" 1419-1425"},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lf/d4lf00275j?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Francelia Sanchez, Debabrata Das, Nathan Episcopo, Felicia S. Manciu, Susheng Tan, Vaithiyalingam Shutthanandan and C. V. Ramana
{"title":"Structure, surface/interface chemistry and optical properties of W-incorporated β-Ga2O3 films made by pulsed laser deposition","authors":"Francelia Sanchez, Debabrata Das, Nathan Episcopo, Felicia S. Manciu, Susheng Tan, Vaithiyalingam Shutthanandan and C. V. Ramana","doi":"10.1039/D4LF00257A","DOIUrl":"https://doi.org/10.1039/D4LF00257A","url":null,"abstract":"<p >Gallium oxide (Ga<small><sub>2</sub></small>O<small><sub>3</sub></small>), which is one among the ultra-wide band gap materials, is promising for the next generation of electronic and optoelectronic devices due to its fascinating material properties for utilization in extreme environments. In this work, Ga<small><sub>2</sub></small>O<small><sub>3</sub></small> films containing refractory tungsten (W) (GWO or Ga–W–O) were fabricated <em>via</em> pulsed laser deposition (PLD) by varying the oxygen partial pressure (<em>p</em>O<small><sub>2</sub></small>), which is the most important thermodynamic parameter that governs the growth, structure and properties of the resulting multi-component oxide films. The effect of variable <em>p</em>O<small><sub>2</sub></small> on the structure, surface chemistry, chemical bonding, optical properties and photodetector device performance of the resulting Ga–W–O films was studied using X-ray photoelectron spectroscopy, Raman spectroscopy, atomic force microscopy, UV-vis spectroscopy, and photoluminescence spectroscopy measurements. The films containing Ga<small><sub>2</sub></small>O<small><sub>3</sub></small> combined with W exhibited no secondary phase development. The impact of W on the chemical and optical characteristics of Ga<small><sub>2</sub></small>O<small><sub>3</sub></small> films was found to be substantial. W<small><sup>5+</sup></small> formation is prevalent when the adatom mobility is high at lower working pressure, whereas lower migration energy favors W<small><sup>6+</sup></small> at higher working pressure. In contrast, the valance band maxima (VBM) of the films have a minor shift to higher energies with increasing <em>p</em>O<small><sub>2</sub></small>, confirming the dominance of O 2p states on VBM in PLD GWO films. Additionally, there is not much change in the optical band gap, but it shows a slight blue shift of the luminescence peak, directing a selective W incorporation into the Ga<small><sub>2</sub></small>O<small><sub>3</sub></small> matrix. The processing conditions were optimized to demonstrate the excellent performance UV-photodetectors based on PLD GWO films. The structure–property correlation established will be useful in the production of W-alloyed β-Ga<small><sub>2</sub></small>O<small><sub>3</sub></small> films with superior structural and optical properties for integration into optoelectronic and photonic device applications.</p>","PeriodicalId":101138,"journal":{"name":"RSC Applied Interfaces","volume":" 6","pages":" 1395-1409"},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lf/d4lf00257a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuan Zeng, Yu Xie, Andrea L. Rodarte, Tyler J. Dill and Andrea R. Tao
{"title":"Probing Raman enhancements for a colloidal metasurface with optical gap distances in the quantum regime†","authors":"Yuan Zeng, Yu Xie, Andrea L. Rodarte, Tyler J. Dill and Andrea R. Tao","doi":"10.1039/D4LF00127C","DOIUrl":"https://doi.org/10.1039/D4LF00127C","url":null,"abstract":"<p >While quantum plasmonic behaviors benefit many applications in quantum optics and nanophotonics, they can have detrimental effects in optical processes such as surface-enhanced Raman spectroscopy (SERS). Here, we measure the SERS intensity for a colloidal metasurface composed of Ag nanocubes coupled to an ultra-flat Au backplane to characterize the <em>classical</em>, <em>crossover</em>, and <em>quantum</em> regimes of the metasurface as a function of gap distance. Gap distance is controlled <em>via</em> chemical modification of the nanocube and backplane surface with self-assembled monolayers composed of alkanethiols with varying chain lengths. Electrodynamic simulations employing a quantum-corrected model are used to characterize the hybrid plasmon modes and charge transfer plasmon modes of the metasurface with respect to gap distance. These results indicate the importance of charge transfer effects in dictating SERS intensities for even relatively large optical gap distances due to the presence of molecular analytes.</p>","PeriodicalId":101138,"journal":{"name":"RSC Applied Interfaces","volume":" 6","pages":" 1410-1418"},"PeriodicalIF":0.0,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lf/d4lf00127c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Riku Mizusaki, Shinsuke Maekawa, Takehiro Seshimo, Takahiro Dazai, Kazufumi Sato, Kan Hatakeyama-Sato, Yuta Nabae and Teruaki Hayakawa
{"title":"Dual function of precisely modified hydroxy-PS-b-PMMA as neutral layers and thin films for perpendicularly oriented lamella†","authors":"Riku Mizusaki, Shinsuke Maekawa, Takehiro Seshimo, Takahiro Dazai, Kazufumi Sato, Kan Hatakeyama-Sato, Yuta Nabae and Teruaki Hayakawa","doi":"10.1039/D4LF00197D","DOIUrl":"https://doi.org/10.1039/D4LF00197D","url":null,"abstract":"<p >We propose a facile and fast control method to obtain perpendicularly oriented microphase-separated structures in block copolymer (BCP) thin films for nanopatterning with a BCP lithography technique. By synthesizing a derivative of polystyrene-<em>block</em>-poly(methyl methacrylate) (PS-<em>b</em>-PMMA) with precisely introduced two hydroxy groups at the junction (PS-(OH)<small><sub>2</sub></small>-PMMA) and by applying it onto silicon substrates, we investigated the lamellar orientations in PS-(OH)<small><sub>2</sub></small>-PMMA thin films with respect to the annealing time of neutral layers (NLs) for modifying silicon substrates to neutralize the interfacial free energies between the substrate and each block component in the BCP thin films. Various NLs, including PS-(OH)<small><sub>2</sub></small>-PMMA itself, were applied onto silicon substrates, and PS-(OH)<small><sub>2</sub></small>-PMMA has turned out to take a dual role of BCP thin films for nanopatterning and NLs, which shows its supremacy over other methods. PS-(OH)<small><sub>2</sub></small>-PMMA needs only 20 minutes of annealing to form NLs that sufficiently neutralize the substrates and induce perpendicular lamellae, which is a significant improvement over non-functionalized PS-<em>b</em>-PMMA. This result highlights the enhanced adsorbability of BCP neutral layers by the introduction of only a small amount of hydroxy groups.</p>","PeriodicalId":101138,"journal":{"name":"RSC Applied Interfaces","volume":" 1","pages":" 74-81"},"PeriodicalIF":0.0,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/lf/d4lf00197d?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ranjana Venugopal, Anjitha Dinakaran, Meenu C. Nair, Arathy C. Balachandran, Nayan Dev Madhavan and Biswapriya Deb
{"title":"Electrochromic properties of MnO2/WO3 bilayered electrodes for enhanced charge storage and superior stability†","authors":"Ranjana Venugopal, Anjitha Dinakaran, Meenu C. Nair, Arathy C. Balachandran, Nayan Dev Madhavan and Biswapriya Deb","doi":"10.1039/D4LF00198B","DOIUrl":"https://doi.org/10.1039/D4LF00198B","url":null,"abstract":"<p >Electrochromic devices (ECDs), which combine optical modulation and energy storage, have sparked widespread interest in window/façade applications and are becoming increasingly popular for energy conservation. It is established that by adjusting the electrochromic (EC) layer surface, the charge–discharge profile and the optical output can be individually regulated. Here, EC bilayers were created by overcoating MnO<small><sub>2</sub></small> on both amorphous and crystalline WO<small><sub>3</sub></small> thin films. The heterojunction considerably improved the cyclic stability and charge storage capacity of the WO<small><sub>3</sub></small> electrode, without affecting the EC functions. The presence of the MnO<small><sub>2</sub></small> layer has significantly enhanced both the areal capacitance and volumetric capacitance of the electrodes. The crystalline WO<small><sub>3</sub></small> electrodes have a peak volumetric capacitance of 341 F cm<small><sup>−3</sup></small> at 0.1 mA cm<small><sup>−2</sup></small> discharge current, associated with an impressive retention rate of 50% even when charging at a higher rate of 1.0 mA cm<small><sup>−2</sup></small>. The ECDs exhibited outstanding visible and IR blocking capability of around 98% beyond 600 nm. A comprehensive study employing spectroscopy and electrochemistry was performed to examine the chemical and electrochemical effects of MnO<small><sub>2</sub></small> overcoating. The results showed that these bilayers may be effectively employed to create EC energy storage devices (EESD) that are both highly stable and superior in performance.</p>","PeriodicalId":101138,"journal":{"name":"RSC Applied Interfaces","volume":" 6","pages":" 1382-1394"},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lf/d4lf00198b?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annabelle M. K. Hadley, Sakshi Gautam and Byron D. Gates
{"title":"Niobium oxide coatings on nanostructured platinum electrocatalysts: benefits and limitations†","authors":"Annabelle M. K. Hadley, Sakshi Gautam and Byron D. Gates","doi":"10.1039/D4LF00211C","DOIUrl":"https://doi.org/10.1039/D4LF00211C","url":null,"abstract":"<p >Development of durable nanoscale electrocatalysts is an important step towards improving the affordability and sustainability of fuel cell technology. Nanostructured platinum catalysts are used to facilitate the two half reactions for hydrogen fuel cells. The sluggish kinetics of the cathodic oxygen reduction reaction and the less than optimal stability of cathode catalysts provide motivation for additional efforts to improve the catalytic performance of platinum. Metal oxide coatings on electrocatalysts have been found to increase durability of nanostructured catalysts and to impart additional properties such as increased activity and resistance to poisoning by contaminants. Niobium oxides have been studied as supporting materials for platinum fuel cell catalysts and shown to have a relatively high stability. It has also been suggested that niobium oxides can impart an increased activity due to strong metal support interactions. However, the lack of electrical conductivity of niobium pentoxide limits its viability as a support. Herein, coatings of niobium oxide were applied to nanotextured platinum catalysts prepared by electrodeposition against self-assembled templates to explore the impact of the coatings on the durability and electrocatalytic activity of the catalyst both during and after an accelerated stress test. The catalysts were characterized <em>via</em> scanning electron microscopy, X-ray photoelectron spectroscopy, conductive atomic force microscopy, and electrochemical techniques. Increasing the thickness of the coating from ∼0.5 nm to ∼4.5 nm was found to preserve the initial nanostructured morphology of the electrodeposited platinum catalyst. The thicker coatings did, however, result in larger charge transfer resistances towards the oxygen reduction reaction. These studies provide further evidence of the utility of ultrathin coatings to improve the properties of nanostructured electrocatalysts.</p>","PeriodicalId":101138,"journal":{"name":"RSC Applied Interfaces","volume":" 6","pages":" 1334-1347"},"PeriodicalIF":0.0,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lf/d4lf00211c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}