A simple, easy-handling, and ultrasensitive quantitative analysis of platinum (Pt) component based on ultraviolet-visible (UV-Vis) spectroscopy is carried out to determine the real Pt loading on glass-carbon electrode. On the basis of the acquired data, the electrochemical active surface area (ECSA) and the peak current (Ip) of methanol electrochemical oxidation as the indicative parameters of the model catalyst (commercial platinum/carbon (Pt/C)) are calculated precisely. For the comparison purpose, the ECSA and Ip are also specified by the theoretical Pt loading calculated based on the Pt content of bulk materials and the ink coating on electrode. The results show that the relative standard deviations of both the ECSA and Ip averaged by real Pt loading decrease significantly, indicating that the data calibrated by real Pt content reflect the intrinsical properties of the commercial Pt/C. Our research may help to increase the accuracy of Pt-containing catalyst evaluation, make the data in different reports comparable, and improve performance of fuel cell catalysts.
[1] Liu M M, Zhang R Z, Chen W. Graphene-supported nanoelectrocatalysts for fuel cells: synthesis, properties, and applications [J]. Chem Rev, 2014, 114(10):5 117-5 160.
[2] Muthuswamy N, de la Fuente JLG, Ochal P, et al. Towards a highly-efficient fuel-cell catalyst: optimization of Pt particle size, supports and surface-oxygen group concentration[J]. Phys Chem Chem Phys, 2013,15(11):3 803-3 813.
[3] Li Y G, Zhou W, Wang H L, et al. An oxygen reduction electrocatalyst based on carbon nanotube-graphene complexes [J]. Nat Nanotechnol, 2012, 7(6): 394-400.
[4] Sharma S, Pollet B G. Support materials for PEMFC and DMFC electrocatalysts:a review [J]. J Power Sources, 2012, 208: 96-119.
[5] Li T, Xue R J, Xue Q, et al. Fabrication of capping-free Pt/porous RGO hybrids by a repeatable-using reduction material and their application in methanol electrooxidation [J]. Chem Phys Lett, 2015, 620: 73-77.
[6] Antolini E. Graphene as a new carbon support for low-temperature fuel cell catalysts [J]. Appl Catal B, 2012, 123-124: 52-68.
[7] He D P, Jiang Y L, Lv H F, et al. Nitrogen-doped reduced graphene oxide supports for noble metal catalysts with greatly enhanced activity and stability [J]. Appl Catal B, 2013, 132-133: 379-388.
[8] Sahoo N G, Pan Y Z, Li L, et al. Graphene-Based Materials for Energy Conversion [J]. Adv Mater, 2012, 24(30): 4 203-4 210.
[9] Tang J, Wang T, Sun X, et al. Novel synthesis of reduced graphene oxide-ordered mesoporous carbon composites and their application in electrocatalysis[J]. Electrochim Acta, 2013, 90: 53-62.
[10] Pumera M. Graphene-based nanomaterials and their electrochemistry [J]. Chem Soc Rev, 2010,39(11):4 146-4 157.
[11] Minakata K, Nozawa H, Yamagishi I, et al. MALDI-Q-TOF mass spectrometric determination of gold and platinum in tissues using their diethyldithiocarbamate chelate complexes [J]. Anal Bioanal Chem, 2014, 406(5): 1 331-1 338.
[12] Herincs E, Puschenreiter M, Wenzel W, et al. A novel flow-injection method for simultaneous measurement of platinum (Pt), palladium (Pd) and rhodium (Rh) in aqueous soil extracts of contaminated soil by ICP-OES [J]. J Anal Atom Spectrom, 2013, 28(3): 354-363.
[13] Scaccia S, Goszczynska B. Sequential determination of platinum, ruthenium, and molybdenum in carbon-supported Pt, PtRu, and PtMo catalysts by atomic absorption spectrometry[J]. Talanta, 2004, 63(3): 791-796.
[14] Revanasiddappa H D, Kumar T N K. A highly sensitive spectrophotometric determination of platinum(Iv) using leuco xylene cyanol FF [J]. Anal Bioanal Chem, 2003, 375(2): 319-323.
[15] Muzikar M, Fontàs C, Hidalgo M, et al. A preconcentration system using polyamine metalfix-chelamine resin for the on-line determination of palladium(Ii) and platinum(Iv) by inductively coupled plasma optical emission spectrometry [J]. Talanta, 2006, 70(5): 1 081-1 086.
[16] Castillo M L A, de Torres A G, Alonso E V, et al. Multi-element determination of Pt, Pd and Ir traces in environmental samples by ICP-MS after pre-concentration[J]. Talanta, 2012, 99: 853-858.
[17] Ye J J, Liu S X, Tian M M, et al. Preparation and characterization of magnetic nanoparticles for the on-line determination of gold, palladium, and platinum in mine samples based on flow injection micro-column preconcentration coupled with graphite furnace atomic absorption spectrometry[J]. Talanta, 2014,118:231-237.
[18] Balcerzak M. Sample digestion methods for the determination of traces of precious metals by spectrometric techniques [J]. Anal Sci, 2002, 18(7): 737-750.
[19] Balcerzak M, Swiecicka E, Balukiewicz E. Determination of platinum and ruthenium in Pt and Pt-Ru catalysts with carbon support by direct and derivative spectrophotometry [J]. Talanta, 1999, 48(1): 39-47.
[20] Balcerzak M, Kaczmarczyk M. Rapid derivative spectrophotometric method for the determination of platinum in Pt-Ru/C catalyst using iodide media [J]. Anal Sci, 2001, 17(11): 1 321-1 324.
[21] Locatelli C. Voltammetric analysis of trace levels of platinum group metals-principles and applications [J]. Electroanalysis, 2007, 19(21): 2 167-2 175.
[22] Locatelli C. Voltammetric Peak area as instrumental datum. a possibility to improve the determination at ultratrace level concentration of platinum group metals (PGMs) and lead. application to particulate matter [J]. Electroanalysis, 2007, 19(4): 445-452.
[23] Giussani B, Roncoroni S, Nemenyi A, et al. A method for the voltammetric determination of platinum at trace levels [J]. Anal Chem, 2014, 86(13): 6 654-6 659.
[24] Lim B, Jiang M J, Camargo P H C, et al. Pd-Pt bimetallic nanodendrites with high activity for oxygen reduction [J]. Science, 2009, 324(5932): 1 302-1 305.
[25] Zhao Y Y, Zhou Y K, Xiong B, et al. Facile single-step preparation of Pt/N-graphene catalysts with improved methanol electrooxidation activity [J]. J Solid State Electrochem, 2013,17(4): 1 089-1 098.
[26] Huang H J, Yang S B, Vajtai R, et al. Pt-decorated 3D architectures built from graphene and graphitic carbon nitride nanosheets as efficient methanol oxidation catalysts [J]. Adv Mater, 2014, 26(30): 5 160-5 165.
