Modelling of Modular Robot Configurations Using Graph Theory

Modular robots are systems that can change its geometry or configuration when connecting more modules or when rearranging them in a different manner to perform a variety of tasks. Graph theory can be used to describe modular robots configurations, hence the possibility to determine the flexibility of the robot to move from one point to another. When the robot’s configurations are represented in a mathematical way, forward kinematics can be obtained

Creació d’un vocabulari interactiu de termes especialitzats aplicats a l’enginyeria electrònica (anglés/castellà/valencià)

[CA] Recerca de la terminologia científica relacionada amb l'Enginyeria Electrònica, per a la creació d'un diccionari interactiu multilingüe (anglés-castellà-valencià). L'objectiu principal del treball és cobrir àrees temàtiques menys investigades en la nostra llengua. Es tracta de proporcionar a la comunitat científica un instrument de consulta lingüística per a l'increment de l'ús correcte dels termes en cadascuna de les llengües implicades en el Projecte. S'aportaran termes, definicions i equivalències en les distintes llengües del treball.Ferre Juan, I. (2018). Creació d’un vocabulari interactiu de termes especialitzats aplicats a l’enginyeria electrònica (anglés/castellà/valencià). Universitat Politècnica de València. http://hdl.handle.net/10251/106409TFG

Understanding the Effect of the Adatoms in the Formic Acid Oxidation Mechanism on Pt(111) Electrodes

The engineered search for new catalysts requires a deep knowledge about reaction mechanisms. Here, with the support of a combination of computational and experimental results, the oxidation mechanism of formic acid on Pt(111) electrodes modified by adatoms of the p block is elucidated for the first time. DFT calculations reveal that some adatoms, such as Bi and Pb, have positive partial charge when they are adsorbed on the bare surface, whereas others, such as Se and S, remain virtually neutral. When the partial charge is correlated with previously reported experimental results for the formic acid oxidation reaction, it is found that the partial positive charge is directly related to the increase in catalytic activity of the modified surface. Further, it is obtained that such a positive partial charge is directly proportional to the electronegativity difference between the adatom and Pt. Thus, the electronegativity difference can be used as an effective descriptor for the expected electrocatalytic activity. This partial positive charge on the adatom drives the formic acid oxidation reaction, since it favors the formation and adsorption of formate on the adatom. Once adsorbed, the neighboring platinum atoms assist in the C–H bond cleavage. Finally, it is found that most of the steps involved in the proposed oxidation mechanism are barrierless, which implies a significant diminution of the activation barriers in comparison to that of the unmodified Pt(111) electrode. This diminution in the activation barrier has been experimentally corroborated for the Bi–Pt(111) electrode, supporting the proposed mechanism.This work has been financially supported by the MINECO (Spain) (project CTQ2013-44083-P) and Generalitat Valenciana (project PROMETEOII/2014/013)

Formic acid oxidation on platinum electrodes: A detailed mechanism supported by experiments and calculations on well-defined surfaces

[EN] In spite of the fact that the formic acid oxidation reaction on electrode surfaces has been extensively investigated, a detailed mechanism explaining all the available experimental evidence on platinum has not been yet described. Herein, using a combined experimental and computational approach, the key elements in the mechanism of the formic acid oxidation reaction on platinum have been completely elucidated, not only for the direct path, through an active intermediate, but also for the CO formation route. The experimental results suggest that the direct oxidation path on platinum takes place in the presence of bidentate adsorbed formate. However, the results reported here provide evidence that this species is not the active intermediate. Monodentate adsorbed formate, whose evolution to the much more favorable bidentate form would be hindered by the presence of neighboring adsorbates, has been found to be the true active intermediate. Moreover, it is found that adsorbed formic acid would have a higher acid constant than in solution, which suggests that adsorbed formate can be originated not only from solution formate but also from formic acid. The CO formation path on platinum can proceed, also from monodentate adsorbed formate, through a dehydrogenation process toward the surface, during which the adsorbate transitions from a Pt-O adsorption mode to a Pt-C one, to form carboxylate. From this last configuration, the C-OH bond is cleaved, on the surface, yielding adsorbed CO and OH. The results and mechanisms reported here provide the best explanation for the whole of the experimental evidence available to date about this reaction, including pH, surface structure and electrode potential effects.This work has been financially supported by the MCINN-FEDER (Spain) and Generalitat Valenciana (Feder) through projects CTQ2016-76221-P and PROMETEOII/2014/013, respectively.Ferre Vilaplana, A.; Perales, JV.; Buso-Rogero, C.; Feliu, J.; Herrero, E. (2017). Formic acid oxidation on platinum electrodes: A detailed mechanism supported by experiments and calculations on well-defined surfaces. Journal of Materials Chemistry A. 5(41):21773-21784. https://doi.org/10.1039/c7ta07116gS2177321784541Bagotzky, V. S., Vassiliev, Y. B., & Khazova, O. A. (1977). Generalized scheme of chemisorption, electrooxidation and electroreduction of simple organic compounds on platinum group metals. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 81(2), 229-238. doi:10.1016/s0022-0728(77)80019-3Beden, B., Bewick, A., & Lamy, C. (1983). A comparative study of formic acid adsorption on a platinum electrode by both electrochemical and emirs techniques. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 150(1-2), 505-511. doi:10.1016/s0022-0728(83)80230-7Capon, A., & Parsons, R. (1973). The oxidation of formic acid at noble metal electrodes Part III. Intermediates and mechanism on platinum electrodes. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 45(2), 205-231. doi:10.1016/s0022-0728(73)80158-5Capon, A., & Parson, R. (1973). The oxidation of formic acid at noble metal electrodes. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 44(1), 1-7. doi:10.1016/s0022-0728(73)80508-xWolter, O., Willsau, J., & Heitbaum, J. (1985). Reaction Pathways of the Anodic Oxidation of Formic Acid on Pt Evidenced by 18O Labeling—A DEMS Study. Journal of The Electrochemical Society, 132(7), 1635-1638. doi:10.1149/1.2114179Willsau, J., & Heitbaum, J. (1986). Analysis of adsorbed intermediates and determination of surface potential shifts by dems. Electrochimica Acta, 31(8), 943-948. doi:10.1016/0013-4686(86)80008-1Chen, Y. X., Miki, A., Ye, S., Sakai, H., & Osawa, M. (2003). Formate, an Active Intermediate for Direct Oxidation of Methanol on Pt Electrode. Journal of the American Chemical Society, 125(13), 3680-3681. doi:10.1021/ja029044tSamjeské, G., & Osawa, M. (2005). Current Oscillations during Formic Acid Oxidation on a Pt Electrode: Insight into the Mechanism by Time-Resolved IR Spectroscopy. Angewandte Chemie International Edition, 44(35), 5694-5698. doi:10.1002/anie.200501009Cuesta, A., Cabello, G., Gutiérrez, C., & Osawa, M. (2011). Adsorbed formate: the key intermediate in the oxidation of formic acid on platinum electrodes. Physical Chemistry Chemical Physics, 13(45), 20091. doi:10.1039/c1cp22498kCuesta, A., Cabello, G., Osawa, M., & Gutiérrez, C. (2012). Mechanism of the Electrocatalytic Oxidation of Formic Acid on Metals. ACS Catalysis, 2(5), 728-738. doi:10.1021/cs200661zChen, Y.-X., Heinen, M., Jusys, Z., & Behm, R. J. (2006). Bridge-Bonded Formate:  Active Intermediate or Spectator Species in Formic Acid Oxidation on a Pt Film Electrode?†. Langmuir, 22(25), 10399-10408. doi:10.1021/la060928qChen, Y. X., Heinen, M., Jusys, Z., & Behm, R. J. (2006). Kinetics and Mechanism of the Electrooxidation of Formic Acid—Spectroelectrochemical Studies in a Flow Cell. Angewandte Chemie International Edition, 45(6), 981-985. doi:10.1002/anie.200502172Chen, Y.-X., Heinen, M., Jusys, Z., & Behm, R. J. (2007). Kinetic Isotope Effects in Complex Reaction Networks: Formic Acid Electro-Oxidation. ChemPhysChem, 8(3), 380-385. doi:10.1002/cphc.200600520Joo, J., Uchida, T., Cuesta, A., Koper, M. T. M., & Osawa, M. (2013). Importance of Acid–Base Equilibrium in Electrocatalytic Oxidation of Formic Acid on Platinum. Journal of the American Chemical Society, 135(27), 9991-9994. doi:10.1021/ja403578sJoo, J., Uchida, T., Cuesta, A., Koper, M. T. M., & Osawa, M. (2014). The effect of pH on the electrocatalytic oxidation of formic acid/formate on platinum: A mechanistic study by surface-enhanced infrared spectroscopy coupled with cyclic voltammetry. Electrochimica Acta, 129, 127-136. doi:10.1016/j.electacta.2014.02.040Brimaud, S., Solla-Gullón, J., Weber, I., Feliu, J. M., & Behm, R. J. (2014). Formic Acid Electrooxidation on Noble-Metal Electrodes: Role and Mechanistic Implications of pH, Surface Structure, and Anion Adsorption. ChemElectroChem, 1(6), 1075-1083. doi:10.1002/celc.201400011Perales-Rondón, J. V., Brimaud, S., Solla-Gullón, J., Herrero, E., Jürgen Behm, R., & Feliu, J. M. (2015). Further Insights into the Formic Acid Oxidation Mechanism on Platinum: pH and Anion Adsorption Effects. Electrochimica Acta, 180, 479-485. doi:10.1016/j.electacta.2015.08.155Clavilier, J., Parsons, R., Durand, R., Lamy, C., & Leger, J. M. (1981). Formic acid oxidation on single crystal platinum electrodes. Comparison with polycrystalline platinum. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 124(1-2), 321-326. doi:10.1016/s0022-0728(81)80311-7Adžić, R. R., Tripković, A. V., & O’Grady, W. E. (1982). Structural effects in electrocatalysis. Nature, 296(5853), 137-138. doi:10.1038/296137a0Ferre-Vilaplana, A., Perales-Rondón, J. V., Feliu, J. M., & Herrero, E. (2014). Understanding the Effect of the Adatoms in the Formic Acid Oxidation Mechanism on Pt(111) Electrodes. ACS Catalysis, 5(2), 645-654. doi:10.1021/cs501729jPerales-Rondón, J. V., Herrero, E., & Feliu, J. M. (2015). On the activation energy of the formic acid oxidation reaction on platinum electrodes. Journal of Electroanalytical Chemistry, 742, 90-96. doi:10.1016/j.jelechem.2015.02.003Clavilier, J., Armand, D., Sun, S. G., & Petit, M. (1986). Electrochemical adsorption behaviour of platinum stepped surfaces in sulphuric acid solutions. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 205(1-2), 267-277. doi:10.1016/0022-0728(86)90237-8C. Korzeniewski , V.Climent and J. M.Feliu, in Electroanalytical Chemistry: A Series of Advances, ed. A. J. Bard and C. Zoski, CRC Press, Boca Raton, 2012, vol. 24, pp. 75–169N. Garcia-Araez , V.Climent and J.Feliu, in Mod Asp Electrochem, ed. C. G. Vayenas, Springer, New York, 2011, vol. 51, ch. 1, pp. 1–105Grozovski, V., Climent, V., Herrero, E., & Feliu, J. M. (2009). Intrinsic Activity and Poisoning Rate for HCOOH Oxidation at Pt(100) and Vicinal Surfaces Containing Monoatomic (111) Steps. ChemPhysChem, 10(11), 1922-1926. doi:10.1002/cphc.200900261Delley, B. (1990). An all‐electron numerical method for solving the local density functional for polyatomic molecules. The Journal of Chemical Physics, 92(1), 508-517. doi:10.1063/1.458452Delley, B. (2002). Hardness conserving semilocal pseudopotentials. Physical Review B, 66(15). doi:10.1103/physrevb.66.155125Hammer, B., Hansen, L. B., & Nørskov, J. K. (1999). Improved adsorption energetics within density-functional theory using revised Perdew-Burke-Ernzerhof functionals. Physical Review B, 59(11), 7413-7421. doi:10.1103/physrevb.59.7413Delley, B. (2000). From molecules to solids with the DMol3 approach. The Journal of Chemical Physics, 113(18), 7756-7764. doi:10.1063/1.1316015Delley, B. (2006). The conductor-like screening model for polymers and surfaces. Molecular Simulation, 32(2), 117-123. doi:10.1080/08927020600589684Neugebauer, J., & Scheffler, M. (1992). Adsorbate-substrate and adsorbate-adsorbate interactions of Na and K adlayers on Al(111). Physical Review B, 46(24), 16067-16080. doi:10.1103/physrevb.46.16067Henkelman, G., & Jónsson, H. (2000). Improved tangent estimate in the nudged elastic band method for finding minimum energy paths and saddle points. The Journal of Chemical Physics, 113(22), 9978-9985. doi:10.1063/1.1323224Keith, J. A., & Jacob, T. (2010). Theoretical Studies of Potential-Dependent and Competing Mechanisms of the Electrocatalytic Oxygen Reduction Reaction on Pt(111). Angewandte Chemie International Edition, 49(49), 9521-9525. doi:10.1002/anie.201004794Monkhorst, H. J., & Pack, J. D. (1976). Special points for Brillouin-zone integrations. Physical Review B, 13(12), 5188-5192. doi:10.1103/physrevb.13.5188Grozovski, V., Vidal-Iglesias, F. J., Herrero, E., & Feliu, J. M. (2011). Adsorption of Formate and Its Role as Intermediate in Formic Acid Oxidation on Platinum Electrodes. ChemPhysChem, 12(9), 1641-1644. doi:10.1002/cphc.201100257Rodes, A., Pastor, E., & Iwasita, T. (1994). An FTIR study on the adsorption of acetate at the basal planes of platinum single-crystal electrodes. Journal of Electroanalytical Chemistry, 376(1-2), 109-118. doi:10.1016/0022-0728(94)03585-7Xu, J., Yuan, D., Yang, F., Mei, D., Zhang, Z., & Chen, Y.-X. (2013). On the mechanism of the direct pathway for formic acid oxidation at a Pt(111) electrode. Physical Chemistry Chemical Physics, 15(12), 4367. doi:10.1039/c3cp44074ePerales-Rondón, J. V., Herrero, E., & Feliu, J. M. (2014). Effects of the anion adsorption and pH on the formic acid oxidation reaction on Pt(111) electrodes. Electrochimica Acta, 140, 511-517. doi:10.1016/j.electacta.2014.06.057Herrero, E., Franaszczuk, K., & Wieckowski, A. (1994). Electrochemistry of Methanol at Low Index Crystal Planes of Platinum: An Integrated Voltammetric and Chronoamperometric Study. The Journal of Physical Chemistry, 98(19), 5074-5083. doi:10.1021/j100070a022Wang, H.-F., & Liu, Z.-P. (2009). Formic Acid Oxidation at Pt/H2O Interface from Periodic DFT Calculations Integrated with a Continuum Solvation Model. The Journal of Physical Chemistry C, 113(40), 17502-17508. doi:10.1021/jp9059888Schwarz, K. A., Sundararaman, R., Moffat, T. P., & Allison, T. C. (2015). Formic acid oxidation on platinum: a simple mechanistic study. Physical Chemistry Chemical Physics, 17(32), 20805-20813. doi:10.1039/c5cp03045ePerales-Rondón, J. V., Ferre-Vilaplana, A., Feliu, J. M., & Herrero, E. (2014). Oxidation Mechanism of Formic Acid on the Bismuth Adatom-Modified Pt(111) Surface. Journal of the American Chemical Society, 136(38), 13110-13113. doi:10.1021/ja505943hClavilier, J. (1987). Pulsed linear sweep voltammetry with pulses of constant level in a potential scale, a polarization demanding condition in the study of platinum single crystal electrodes. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 236(1-2), 87-94. doi:10.1016/0022-0728(87)88020-8Fernandez-Vega, A., Feliu, J. M., Aldaz, A., & Clavilier, J. (1991). Heterogeneous electrocatalysis on well-defined platinum surfaces modified by controlled amounts of irreversibly adsorbed adatoms. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 305(2), 229-240. doi:10.1016/0022-0728(91)85521-pGrozovski, V., Climent, V., Herrero, E., & Feliu, J. M. (2010). Intrinsic activity and poisoning rate for HCOOH oxidation on platinum stepped surfaces. Physical Chemistry Chemical Physics, 12(31), 8822. doi:10.1039/b925472bGrozovski, V., Solla-Gullón, J., Climent, V., Herrero, E., & Feliu, J. M. (2010). Formic Acid Oxidation on Shape-Controlled Pt Nanoparticles Studied by Pulsed Voltammetry. The Journal of Physical Chemistry C, 114(32), 13802-13812. doi:10.1021/jp104755bKoper, M. T. M. (2013). Theory of multiple proton–electron transfer reactions and its implications for electrocatalysis. Chemical Science, 4(7), 2710. doi:10.1039/c3sc50205hKoper, M. T. M. (2015). Volcano Activity Relationships for Proton-Coupled Electron Transfer Reactions in Electrocatalysis. Topics in Catalysis, 58(18-20), 1153-1158. doi:10.1007/s11244-015-0489-3Neurock, M., Janik, M., & Wieckowski, A. (2009). A first principles comparison of the mechanism and site requirements for the electrocatalytic oxidation of methanol and formic acid over Pt. Faraday Discuss., 140, 363-378. doi:10.1039/b804591gGao, W., Keith, J. A., Anton, J., & Jacob, T. (2010). Theoretical Elucidation of the Competitive Electro-oxidation Mechanisms of Formic Acid on Pt(111). Journal of the American Chemical Society, 132(51), 18377-18385. doi:10.1021/ja1083317Gamboa-Aldeco, M. E., Herrero, E., Zelenay, P. S., & Wieckowski, A. (1993). Adsorption of bisulfate anion on a Pt(100) electrode: A comparison with Pt(111) and Pt(poly). Journal of Electroanalytical Chemistry, 348(1-2), 451-457. doi:10.1016/0022-0728(93)80151-7Clavilier, J., & Sun, S. G. (1986). Electrochemical study of the chemisorbed species formed from formic acid dissociation at platinum single crystal electrodes. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 199(2), 471-480. doi:10.1016/0022-0728(86)80021-3Sun, S. G., Clavilier, J., & Bewick, A. (1988). The mechanism of electrocatalytic oxidation of formic acid on Pt (100) and Pt (111) in sulphuric acid solution: an emirs study. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 240(1-2), 147-159. doi:10.1016/0022-0728(88)80319-xHerrero, E., Fernández-Vega, A., Feliu, J. M., & Aldaz, A. (1993). Poison formation reaction from formic acid and methanol on Pt(111) electrodes modified by irreversibly adsorbed Bi and As. Journal of Electroanalytical Chemistry, 350(1-2), 73-88. doi:10.1016/0022-0728(93)80197-pHerrero, E., Feliu, J. M., & Aldaz, A. (1994). Poison formation reaction from formic acid on Pt(100) electrodes modified by irreversibly adsorbed bismuth and antimony. Journal of Electroanalytical Chemistry, 368(1-2), 101-108. doi:10.1016/0022-0728(93)03032-kIwasita, T., Xia, X., Herrero, E., & Liess, H.-D. (1996). Early Stages during the Oxidation of HCOOH on Single-Crystal Pt Electrodes As Characterized by Infrared Spectroscopy. Langmuir, 12(17), 4260-4265. doi:10.1021/la960264sCorrigan, D. S., & Weaver, M. J. (1988). Mechanisms of formic acid, methanol, and carbon monoxide electrooxidation at platinum as examined by single potential alteration infrared spectroscopy. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 241(1-2), 143-162. doi:10.1016/0022-0728(88)85123-4Chang, S. C., Leung, L. W. H., & Weaver, M. J. (1990). Metal crystallinity effects in electrocatalysis as probed by real-time FTIR spectroscopy: electrooxidation of formic acid, methanol, and ethanol on ordered low-index platinum surfaces. The Journal of Physical Chemistry, 94(15), 6013-6021. doi:10.1021/j100378a072Clavilier, J., Fernandez-Vega, A., Feliu, J. M., & Aldaz, A. (1989). Heterogeneous electrocatalysis on well defined platinum surfaces modified by controlled amounts of irreversibly adsorbed adatoms. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 258(1), 89-100. doi:10.1016/0022-0728(89)85164-2Herrero, E., Climent, V., & Feliu, J. M. (2000). On the different adsorption behavior of bismuth, sulfur, selenium and tellurium on a Pt(775) stepped surface. Electrochemistry Communications, 2(9), 636-640. doi:10.1016/s1388-2481(00)00093-xMaciá, M. (1999). Formic acid self-poisoning on bismuth-modified Pt(755) and Pt(775) electrodes. Electrochemistry Communications, 1(2), 87-89. doi:10.1016/s1388-2481(99)00009-0Maciá, M. D., Herrero, E., Feliu, J. M., & Aldaz, A. (2001). Formic acid self-poisoning on bismuth-modified stepped electrodes. Journal of Electroanalytical Chemistry, 500(1-2), 498-509. doi:10.1016/s0022-0728(00)00389-2Maciá, M. ., Herrero, E., & Feliu, J. . (2002). Formic acid self-poisoning on adatom-modified stepped electrodes. Electrochimica Acta, 47(22-23), 3653-3661. doi:10.1016/s0013-4686(02)00335-3Garcia-Araez, N., Climent, V., Herrero, E., Feliu, J. M., & Lipkowski, J. (2005). Determination of the Gibbs excess of H adsorbed at a Pt(111) electrode surface in the presence of co-adsorbed chloride. Journal of Electroanalytical Chemistry, 582(1-2), 76-84. doi:10.1016/j.jelechem.2005.01.03

Ethanol Electro-oxidation Reaction Selectivity on Platinum in Aqueous Media

Ethanol fuel cells require selective catalysts for complete oxidation of the fuel, which involves C–C bond cleavage. From experiments on well-defined surfaces and calculations, the mechanism controlling the ethanol electro-oxidation selectivity on platinum in aqueous media as a model system is elucidated. Adsorbed OH favors ethanol adsorption and conversion into adsorbed ethoxy, which favorably evolves to adsorbed COCH3. On Pt(111), adsorbed OH is also readily incorporated into adsorbed COCH3 to yield acetic acid. A higher barrier for this latter step on Pt(100) enables the COCH3 dehydrogenation to adsorbed COCH2, favoring C–C bond cleavage. As adsorbed OH plays an essential role as a reactant in this process, its adsorption properties have a decisive impact on this reaction. Furthermore, the adsorbed OH diffusion rate on the surface, which depends on the adsorbate/media/surface interaction at the interface, modulates the availability of this key reactant. These results highlight that the search for selective electrocatalysts requires holistic consideration of reactants, adsorbates, media, and substrate.This research was funded by Ministerio de Ciencia e Innovación (Spain) grant nos. PID2019-105653GB-I00 and FJC2018-038607-I and Generalitat Valenciana (Spain) grant no. PROMETEO/2020/063

Why Citrate Shapes Tetrahedral and Octahedral Colloidal Platinum Nanoparticles in Water

[EN] The performance of many advanced catalytic systems depends not only on the size and composition but also on the specific shape of the metal nanoparticles (NPs) from which they are assembled. In turn, the shape of colloidal NPs depends on the specific capping agent involved in their synthesis, though the mechanism is still poorly understood. Here, supported by electrochemical experiments, Fourier transform infrared spectra, and density functional theory calculations, on well-defined surfaces, we show how a specific capping agent determines the shape of colloidal NPs. Solvated citrate can become simultaneously adsorbed on the Pt(111) surface through three dehydrogenated carboxylic groups, with each one of them in bidentate configuration. On the other two basal planes, citrate can be adsorbed through only two of them. For this reason, under the synthesis conditions, citrate is more favorably adsorbed on the Pt(111) than on the other two basal planes of platinum. This adsorption behavior explains why colloidal platinum NPs of tetrahedral and octahedral shape are produced when citrate is used as the capping agent in water. The mechanism for citrate would also determine the shape of other pure face-centered cubic metals and can inspire the engineering of future capping agents.This work has been financially supported by the MCINN-FEDER (Spain) through project CTQ2016-76221-P.Gisbert-González, J.; Feliu, J.; Ferre Vilaplana, A.; Herrero, E. (2018). Why Citrate Shapes Tetrahedral and Octahedral Colloidal Platinum Nanoparticles in Water. The Journal of Physical Chemistry C. 122(33):19004-19014. https://doi.org/10.1021/acs.jpcc.8b05195S19004190141223