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The purpose of this study is to improve the surface electrical conductivity and corrosion resistance of AISI430 stainless steel (430 SS) as bipolar plates for direct formic acid fuel cell (DFAFC).

The niobium diffusion layers have been successfully synthesized on 430 SS substrate by the plasma surface diffusion alloying technique under different diffusion alloying time.

The surface morphology of Nb-modified 430 SS prepared under the diffusion alloying time of 2 h is more homogeneous, relatively sleek and compact without surface micropore and other common surface blemishes. The potentiostatic and potentiodynamic polarization measurements manifest that Nb-modified 430 SS prepared under the diffusion alloying time of 2 h enormously ameliorate the corrosion resistance of bare 430 SS compared with other Nb-modified 430 SS samples and its corrosion current density is maintained at −1.4 µA cm⁻² in simulated anodic environment of DFAFC (0.05 M H₂SO₄ + 2 ppm HF + 10 M formic acid at 50 °C).

The effect of diffusion alloying time on the corrosion resistance and surface conductivity of Nb-modified 430 SS has been carefully studied. The Nb-modified 430 SS samples prepared at the diffusion alloying time of 2 h have the best surface electrical conductivity and corrosion resistance in the simulated anodic environment of DFAFC.

Fuel cells technologies are the most promising green energy technologies for diverse applications. One of the fastest growing areas is the portable electronic applications where the power range is the order of 1–100 W. For most of the portable electronic devices, rechargeable battery is the major energy source. Due to limitations like limited capacity, requirement of external power for recharge have led many researchers to look for alternative power sources to power portable electronic devices. The high energy density of fuel cells makes them very attractive alternative to batteries for portable power applications. There are a variety of fuel cell technologies being considered to replace batteries in portable electronic equipment. Direct Liquid Fuel Cells (DLFCs) have attracted much attention due to their potential applications as a power source for portable electronic devices. The advantages of DLFCs over hydrogen fed PEM fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. Unlike batteries, fuel cells need not be recharged, merely refueled. This paper provides an overview on challenges of DLFCs (Direct Liquid Fuel Cells), like fuel crossover, cost, durability, water management, weight and size along with approaches being investigated to solve these challenges. Portable Fuel Cell Commercialization Targets for future and producers of portable fuel cells across the globe are also discussed in this paper.

The purpose of this paper is to evaluate the protection against corrosion of carbon steel SAE 1020 promoted by a niobium- and titanium-based coating produced from a resin obtained by the Pechini method.

A resin was prepared with ammonium niobium oxalate as niobium precursor and K₂TiF₆ as titanium precursor. Carbon Steel SAE 1020 plates were dip coated in the resin and calcinated for 1 h at 600 ºC. Scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction were used to characterize the coating morphologically and structurally. Open circuit potential, electrochemical impedance spectroscopy, anodic potentiodynamic polarization and scanning vibrating electrode technique were used to evaluate the corrosion protection of the coating.

The electrochemical analyses evidence slight protection against corrosion of the coating by itself; however, the needle-like crystal structure obtained may potentially provide a good anchorage site, suggesting the coating could be used as a pretreatment that may present similar application to phosphating processes, generating lower environmental impacts.

Due to increasingly restrictive environmental laws, new environmentally friendlier surface treatments must be researched. This paper approaches this matter using a combination of niobium- and titanium-based coating, produced by a cleaner process, the Pechini method.