Bio-Based Graphene Sheet/Copolymer Composite as Supporting Material for Nanocatalysts towards Electrochemical Studies and Direct Alkaline Alcohol Fuel Cells

In this work, graphene carbon sheets (BGS) were prepared from writing paper and lemon peel, and its polymer composite has a higher surface area compared with the existing Vulcan carbon. Further, the use of lead as a promoter for the oxidation of alcohol and CO on platinum-supported poly(amine-terminated cyclophosphazene-co-cyclophosphazene)-biobased graphene sheet (Poly(AFCP-co-CP)-BGS) composite was demonstrated. The size, phase morphology, and distribution of metal nanoparticles on Poly(AFCP-co-CP)-BGS composite as well as the formation of composite based catalysts were confirmed from TEM, XRD, and FTIR studies. The catalytic activity and stability of the prepared catalysts were tested and compared to methanol, ethylene glycol, glycerol, and CO in 0.5 M KOH solution. The results conclude that the lead-doped Pt/Poly(AFCP-co-CP)-BGS catalyst shows higher oxidation current with respect to onset potential and lower I f / I r ratio for alcohol as well as CO oxidation. In addition, Pt-Pb/Poly(AFCP-co-CP)-BGS catalyst was checked for direct alkaline fuel cells and proved as a potent anode catalyst in alkaline medium for real-time fuel battery applications. In addition, Poly(AFCP-co-CP)-BGS composite also promotes the catalytic reaction compared to Poly(AFCP-co-CP) and BGS supports as noticed from methanol oxidation in alkaline medium. The surface area of the prepared supporting material is 750.72 m2g-1, which is higher than the activated carbon (250.12m2g-1). So, the prepared Poly(AFCP-co-CP)-BGS composite is a potent support for metal deposition, electrooxidation, and single stack fuel cell constructions.

Pt/Mn3O4 cubes with high anti-poisoning ability for C1 and C2 alcohol fuel oxidation

Pt anchored over Mn3O4 cubes are found to have high anti-CO poisoning ability for C1 and C2 alcohol fuel oxidation in the acid electrolyte resulting from the electronic effect induced...

Nickel Foam Electrode with Low Catalyst Loading and High Performance for Alkaline Direct Alcohol Fuel Cells

Nickel foam has a unique three-dimensional (3-D) network structure that helps to effectively utilize catalysts and is often used as an electrode support material for alkaline direct alcohol fuel cells. In this chapter, first, the effect of nickel foam thickness on cell performance is explored. The results show that the thickness affects both mass transfer and electron conduction, and there is an optimal thickness. The thinner the nickel foam is, the better the conductivity is. However, the corresponding three-dimensional space becomes narrower, which results in a partial agglomeration of the catalyst and the hindrance of mass transfer. The cell performance of 0.6 mm nickel foam electrode is better than that of 0.3 and 1.0 mm. Secondly, to fully exert the catalytic function of the catalyst even at a lower loading, a mixed acid-etched nickel foam electrode with lower Pd loading (0.35 mg cm−2) is prepared then by a spontaneous deposition method. The maximum power density of the single alkaline direct ethanol fuel cell (ADEFC) can reach 30 mW cm−2, which is twice the performance of the hydrochloric acid treated nickel foam electrode. The performance improvement is attributed to the micro-holes produced by mixed acids etching, which enhances the roughness of the skeleton and improves the catalyst electrochemical active surface area.

USE OF ALCOHOL ADDITIVES FOR ECOLOGICAL GASOLINE PRODUCTION

The purpose of this article is to perform research to improve the stability, quality and efficiency of gasoline-alcohol fuel compositions, as well as obtaining high-octane gasolines corresponding to the modern standards with the addition of alcohols and their mixtures to these gasolines. Research methods: The article considers physicochemical methods for studying the stratification of alcohol-gasoline mixtures, determining the water content in them, as well as determining the octane number of alcohol-gasoline compositions. Results: The raw material base and possibilities of bioethanol production in Ukraine as an ecological additive to gasoline and as a way to increase their octane number were studied. Stratification temperatures of alcohol-gasoline mixtures and octane numbers of A-92 gasoline with different alcohol content were determined. Discussion: It is proposed to use higher concentrations of ethanol (bioethanol) in gasoline mixtures more than 40% of alcohol, because it does not require dehydration. It is proposed to use an additional fuel pump, which would work only for mixing the fuel mixture, to prevent stratification of the fuel-ethanol composition during its long-term storage in the car’s tanks.