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A mesoporous Fe-Ni catalyst was prepared by microwave combustion method by using glycine as a fuel to help the combustion occur in the microwave. The bimetallic catalyst synthesized was intend to accelerate the production of hydrogen via decomposition of formic acid. The hydrogen produced supposedly can substitute the energy source used now especially from fossil fuels to contribute to the reduction of greenhouse effect. The catalyst sample was characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and N 2 adsorption-desorption isotherm (BET). From the BET isotherms, a type IV isotherm was observed, indicate the presence of mesoporous solid. XRD diffractograms of Fe-Ni have welldefined diffraction patterns with strong and sharp diffraction peaks, indicating that they are crystalline. The SEM images show the presence of voids and pores in the sample and spongy structure which also consisted of very fine crystalline. The selectivity for H 2 formation using the prepared bimetallic catalyst was achieved ranging of 94 to 99% for 120 minutes at optimum conversion of formic acid and merely at room temperature.

The reduction behavior of nickel oxide (NiO) and zirconia (Zr) doped NiO (Zr/NiO) was investigated using temperature programmed reduction (TPR) using carbon monoxide (CO) as a reductant and then characterized using X-ray diffraction (XRD), nitrogen absorption isotherm using BET technique and FESEM-EDX. The reduction characteristics of NiO to Ni were examined up to temperature 700 °C and continued with isothermal reduction by 40 vol. % CO in nitrogen. The studies show that the TPR profile of doped NiO slightly shifts to a higher temperature as compared to the undoped NiO which begins at 387 °C and maximum at 461 °C. The interaction between ZrO 2 with Ni leads to this slightly increase by 21 to 56 °C of the reduction temperature. Analysis using XRD confirmed, the increasing percentage of Zr from 5 to 15% speed up the reducibility of NiO to Ni at temperature 550 °C. At this temperature, undoped NiO and 5% Zr/NiO still show some crystallinity present of NiO, but 15% Zr/NiO shows no NiO in crystalline form. Based on the results of physical properties, the surface area for 5% Zr/NiO and 15% Zr/NiO was slightly increased from 6.6 to 16.7 m 2 /g compared to undoped NiO and for FESEM-EDX, the particles size also increased after doped with Zr on to NiO where 5% Zr/NiO particles were 110 ± 5 nm and 15% Zr/NiO 140 ± 2 nm. This confirmed that the addition of Zr to NiO has a remarkable chemical effect on complete reduction NiO to Ni at low reduction temperature (550 °C). This might be due to the formation of intermetallic between Zr/NiO which have new chemical and physical properties.

The depletion of petroleum sources and global warming issues has increased awareness among scientists to produce alternative energy other than the one that we always depend on, which is petroleum. Hydrogen (H2) energy is one of the alternatives that was promising as an efficient and green fuel. Meanwhile, formic acid has been detected as one of the convenient H2 source/storage material. Here, we introduce two heterogeneous catalysts for H2 generation from formic acid. Fe0.1 Zn0.9 and Fe0.5 Zn0.5 were synthesized by a modified microwave method. In this study, we report the result of a detailed study undertaken to investigate the decomposition of formic acid to H2 and carbon dioxide (CO2) using gas chromatography with thermal conductivity detector (GC-TCD). The catalyst used to decompose the formic acid was characterized by x-ray diffraction (XRD) to determine their physicochemical properties. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) were also used to determine the surface morphology and the structure of the synthesized catalysts. The result suggested that in the dehydrogenation reaction, 90-96% of H2 was selectively produced from the formic acid with the presence of FeZn catalyst. For Fe0.1Zn0.9 catalyst, FESEM micrograph shows the particle was well dispersed, existing both away from and close proximity to 50-70 nm in size. Both heterogeneous catalysts are able to produce H2 from formic acid at room temperatures (30°C) with no additives added and with high selectivity.