Oleylaminemediated synthesis of pd nanoparticles for. The size of pd nps can be tuned in a range of 1060 nm simply by adjusting the concentration of pd precursor. Formic acid oxidation at pth2o interface from periodic. Formic acid fac can be synthesized through methyl formate hydrolysis, oxidation of hydrocarbons or hydrolysis of formamide. Direct formic acid fuel cells dfafcs are considered as promising power sources for portable applications with the merits of high opencircuit voltage, small fuel crossover, and low toxicity. Herein, we electrodeposited palladium membranes with periodically ordered mesoporosity obtained by asymmetrically replicating the bicontinuous cubic phase structure of a lyotropic liquid. Without the preadsorbed formate, formic acid is only able to adsorb with its carboxyl o linking to pt, which is however difficult to decompose further.
The oxidation of formic acid is of permanent interest as a model reaction for the mechanistic understanding of the electrooxidation of small. Extraordinary electrocatalytic performance for formic acid. To meet the requirements of potential applications, it is of great importance to explore new catalysts for formic acid oxidation that have both ultrahigh mass activity and co resistance. Pd and pdm m fe or co nanostructured electrocatalysts were synthesized by the impregnation method and supported on carbon black vulcan xc72r for the formic acid oxidation reaction, faor, in acid.
However, co poisoning and particle agglomeration can reduce the catalytic activity. Metal alloys and binary metal catalysts co oxidation. Formic acid fa is an important material in the chemical industry. Pdf electrochemical instability of pt nanoparticles. The catalytic activity and stability of the asobtained pd nps toward formic acid oxidation.
Without using surfactants or polymers, ptcu alloy was firstly prepared through simply coreduction of pt and cu ions using ethylene glycol and sodium citrate as the reducing and stabilizing reagents. The results are compared to those at a polycrystalline platinum electrode surface. For this purpose, different levels of pd nanoparticle loading 0. Electrocatalytic activities towards the electrochemical. The formic acid oxidation reaction has been studied in concentrated perchloric acid solutions up to 9. Highly efficient catalysts are needed for formic acid oxidation.
Cuesta and others published formic acid oxidation on metal electrodes find, read and cite all the research you need on researchgate. Formic acid oxidation on platinum is a structuresensitive reaction that takes place via a mechanism with two paths. Ceria nanocrystals supporting pd for formic acid electrocatalytic. The role of formic acidformate equilibria in the oxidation of formic. Conversion of cellulose into formic acid by ironiii. Pdf formic acid oxidation on metal electrodes researchgate. Developing superior electrocatalysts for formic acid oxidation fao is the most crucial step in commercializing direct formic acid fuel cells. Pdbi alloy nanoparticleenhanced catalytic activity toward. Hence, dfafcs can offer both a high power and an easy fuel handling at ambient conditions 2, 3, 4. The oxidation of formic acid was examined by cyclic voltammetry and chronoamperometry in order to determine the rate of catalytic activity reaction turnover as. The formic acid oxidation reaction faor is a model electrocatalytic reaction involving multiple protoncoupled electron transfer steps. Vanadiumvcatalyzed oxidation with o2 in acidic aqueous media now is the most common method to realize. The activity enhancement is explained by a reduced co poisoning of the surface pt sites.
As a consequence, the current is not entering plateau as on the ptc catalysts. Pdcuau nas exhibit superior mass and specific activities to commercial pd black and pdcuau nas in alkaline solution. Formic acid was first isolated from certain ants and was named after the latin formica, meaning ant. Article formic acid oxidation on pd thin film coated au nanocrystals yongan tang 1,y and shouzhong zou 2,y 1 dod technologies inc. The oxidation of formic acid on different pdcoated au nanocrystals started at around.
Direct formic acid fuel cells dfafcs have received great attention since they combine the fast fuel oxidation rate of h2 pemfcs and the ability of dmfcs to directly utilize the liquid fuel. Pt electrocatalysts have been widely studied for electrocatalysis oxidation of small organic molecules including methanol, ethanol, and formic acid. The formic acid oxidation is enhanced at any of the ptsnc surfaces with sn in the surface layer. The binary particles exhibited much less selfpoisoning and a lower activation energy relative to pt nanocubes, consistent with the single crystal study. Kinetic isotope effects in complex reaction networks.
Singleatom rhndoped carbon electrocatalyst for formic. Formic acid, the simplest of the carboxylic acids, used in processing textiles and leather. Density functional theory calculations reveal that the. By electronic structure analyses, we show that a hydrophobic zone formed nearby the preadsorbed fomate on pt. The methods of catalytic oxidation of biomass in aqueous solutions under oxygen o2 using catalysts is promising, since the conditions are mild, the purity of produced fa is high, and the catalysts can be. Tunable periodically ordered mesoporosity in palladium. It is an unstable colorless liquid which can be produced by mixing formic acid with hydrogen peroxide. Electrocatalytic oxidation of formic acid at an ordered. A kinetic study article in journal of electroanalytical chemistry 5545551. A catalytic study of formic acid oxidation on preferentially oriented. Carbon supported pdm m fe, co electrocatalysts for.
Formic acid oxidation occurs at the anode on a catalyst layer. Binary ptpd nanoparticles were synthesized by localized overgrowth of pd on cubic pt seeds for the investigation of electrocatalytic formic acid oxidation. The oleylaminecoated pd nanoparticles are readily cleaned with a 99% acetic acid wash, and the pd particles supported on ketjen carbon are catalytically active for formic acid oxidation in hclo4 solution. Formic acid is a product of the alphaoxidation of fatty. Electrocatalytic activities towards the electrochemical oxidation of. Abstract formic acid oxidation on platinum is a structure. Despite of repeated research extending over more than. Pdf the formic acid oxidation fao reaction is studied on platinum in acid solutions using a specially designed flow cell and different experimental. The electrocatalytic oxidation of formic acid at a ptbi ordered intermetallic electrode surface has been investigated using cyclic voltammetry, rotating disk electrode rde voltammetry and differential electrochemical mass spectrometry dems. Owing to its oxidizing and disinfecting action, it is used in the chemical, medical and food industries. Surfaces free fulltext formic acid oxidation on pd. The order with respect to formic acid is less than one in the absence of perchloric acid whereas in the presence of perchloric.
A study of pt dissolution during formic acid oxidation acs. Formic acid oxidation at palladium nanoparticles supported. Pdf kinetic study of formic acid oxidation on carbon. Adsorption and oxidation of formic acid on smooth platinum. The fuel molecule, formic acid, has a simple structure hcooh and itself is the intermediate of the oxidation of alcohol molecules. Currently, fa can be produced either from fossil fuel or biomass, the latter being much more sustainable than the former. Pdf modeling electrocatalytic oxidation of formic acid.
Electrochemical instability of pt nanoparticles probed by formic acid oxidation. This work addresses the effects of pd nanoparticle loading and dispersion on the mechanisms of formic acid fa electro oxidation. It is made by the action of sulfuric acid upon sodium formate, which is produced from. Formic acid oxidation on pd thin film coated au nanocrystals. Pdf insight of sn influence on formic acid oxidation at. Pdf formic acid oxidation at platinumbismuth catalysts. In this work, we use the first method since not only uses co as a raw material but it is also the most extended technology for formic acid synthesis worldwide hietala et al. The word formic comes from the latin word for ant, formica, referring to its early isolation by the distillation of ant bodies.
Catalytic oxidation of biomass to formic acid using o2 as. Information obtained from kinetic measurements is the result of a complex combination of different reaction pathways. Full text get a printable copy pdf file of the complete article 863k, or click on a page image below to browse page by page. Performic acid pfa is an organic compound with the formula ch 2 o 3. Insight of sn influence on formic acid oxidation at pt based catalysts. View enhanced pdf access article on wiley online library html view download pdf for offline viewing. One of the paths leads to the formation of co poison intermediate, which. The anodic maximum of formic acid oxidation below 0. Improving the electrochemical oxidation of formic acid by. Cyclic voltammogram of formic acid electrooxidation in 0. Kinetic study of formic acid oxidation on carbonsupported platinum electrocatalyst. Oxidation of lower molecular weight carboxylic acids such as formic, acetic, glyoxalic, and oxalic acids is often the ratecontrolling step during wet oxidation wo of an aqueous waste stream exhibiting very high chemical oxygen demand cod.
A systematic study was conducted on small pd nanocrystals 56 nm to understand the effects of catalyst structure and electrolyte on the oxygen reduction reaction orr and formic acid oxidation fao. Trimetallic synergy in intermetallic ptsnbi nanoplates. A new class of ptsnbi intermetallic nanoplates is synthesized to boost formic acid oxidation, which greatly outperforms binary ptsn and ptbi intermetallic, benefiting from the synergism of chosen three metals. Formic acid oxidation feliu major reference works wiley. In particular, the best catalyst, atomically ordered pt 45 sn 25 bi 30 nanoplates, exhibits an ultrahigh mass activity of 4394 ma mg. The oxidation of formic acid is important as a prototype reaction for the oxidation of small organics and as such has relevance for understanding lowtemperature fuel cells. Kinetics of wet oxidation of formic acid and acetic acid. Both pt catalysts and au electrodes have been used extensively to study hcooh oxidation. Preformed palladium nanoparticles pdnp have been dropcoated onto polyaniline panimodified carbon fibre paper to prepare extended reaction zone anodes for formic acid oxidation that take advantage of the promoting effect of polyaniline.
The role of electrodeposited pd catalyst loading on the. The boron content can be tailored easily by tuning the reaction time, and an optimal boron content is beneficial to promote the formic acid oxidation reaction. The influence of the pani preparation conditions on the activity of the pdnp was investigated. The oxidation rate at each potential was determined as a function of elec trode preparation, ph, and formic acid concentration.
It is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Formic acid oxidation on bi pt111 electrode in perchloric acid media. Pdf insight into the effect of sn on co and formic acid. Formic acid, systematically named methanoic acid, is the simplest carboxylic acid, and has the chemical formula hcooh. The surface active site model for formic acid electrooxidation at. Pdf kinetic study of the formic acid oxidation on steady state.
The excellent electrocatalytic activity of pdpani nanofiber film has been confirmed from the electro oxidation reaction of formic acid in acidic media and alcohols ethanol and methanol in alkaline medium, making it a potential candidate for direct fuel cells dfcs in both acidic and alkaline media. Sizecontrollable synthesis and highperformance formic. The catalyst shows no obvious activity degradation after 1500 cyclic voltammetry cycles under ambient conditions. Pdf kinetics and mechanism of the oxidation of formic. The conversion of abundant renewable cellulose into versatile formic acid fa is a potential process for efficient energy storage and application. The orr activities of pd catalysts strongly depended on their structure and the electrolyte used. Insight into the effect of sn on co and formic acid. Electrooxidation of formic acid, methanol, and ethanol on. As the formic acid solution on the surface of copper film has a certain role in corrosion, using formic acid solution treatment, better surface reduction and rougher surface for cu film were obtained. By electronic structure analyses, we show that a hydrophobic zone formed nearby the preadsorbed fomate on pt 111 is the origin for the promoting role of formate.
Cuesta and others published formic acid oxidation on metal electrodes find, read and cite all the research you. The marked reduction in formic acid production from betamethyl fatty acids in peroxisomedeficient skin fibroblasts suggests that peroxisomes are involved in the generation of c1 units. Surface structure and methanol electrocatalysis ex situ stm images taken during methanol oxidation via uhv transfer. This work reports the synthesis of a novel carbonsupported pddecorated ptcu nanocatalyst for formic acid oxidation. Insight into the effect of sn on co and formic acid oxidation at ptsn catalysts.
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