The development of high-activity catalysts with good selectivity for the direct synthesis of H2O2 from H2 and O2 remains challenging. TiO2–C used as a support material is able to facilitate strong metal–support interactions. We designed catalysts for the direct synthesis of hydrogen peroxide that utilized the synergistic effects of hybrid TiO2–C supports and ordered alloyed PdNi nanoparticles in a neutral reaction solution. Through thermal hydrogen treatment, the ordered structure of the alloyed PdNi nanocatalysts was transformed. 1H NMR was used to measure the amount of water formed as an estimate of selectivity. High-resolution transmission electron microscopy and X-ray photoelectron spectroscopy studies showed an excellent dispersion of the bimetallic PdNi nanocatalyst on the hybrid support. X-ray absorption spectroscopy gave clear evidence of metal–support interactions with electron transfer from the ordered alloyed PdNi nanocatalysts to the defect TiO2–C support, resulting in a noteworthy performance with high H2O2 productivity and selectivity under ambient conditions. This work provides a route to an economically viable alternative to existing Pd-based heterogeneous catalysts for the direct synthesis of hydrogen peroxide.

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New concepts combining thermodynamic and kinetic parameters for designing catalysts with high selectivity.

Although the printing offset technique offered the best printout quality among other printing techniques, however, there is a drawback of the offset technique which needs great skill to handle the process, i.e the presence of trace water molecules on the image area of the plate. The water’s existence in the image area leads to the poor covering of ink which makes the blurry printout than it must be. Therefore, we used various concentrations of propylene glycol such as 0%, 0.05%, and 0.1% as wetting agents to prevent the trace water sticks to the image area of the plate. We used the HVS paper 80 g/m2 as printing material and the machine of Oliver Sakurai 472 ED to study the role of propylene glycol. Propylene glycol has been considered based on stronger interaction with water molecules than the interaction of the image area - propylene glycol. By investigating the visual quality, density, and dot gain of the printout, we concluded that the wetting agent content of PG 0.05% (v/v) increased the visual brightness, and density of the printout, compared to the water only as the wetting solution.

Hydrogen peroxide is an important material for bleaching agent in paper production related to the low price and environmentally friendly chemical. The current production of H2O2 is well-known as indirect synthesis, which uses danger anthraquinone. The synthesis was improved by using the direct reaction of H2 and O2 on Pd or PdAu alloy's catalyst surface and has been known as direct synthesis. The current catalyst used is Pd-Au, but it has limited availability in nature. Therefore we need the alternative of Pd-Au. We investigated Ni alloyed with Pd for the new H2O2 direct synthesis catalyst using a density functional theory approach. We selected the O adsorption to screen the catalysts and compared the species adsorption trend on the surfaces of PdNi and the proven catalysts such as Pd, PdAu, and PdHg. Since the trend of O adsorption on the PdAu and PdNi is similar, it can be concluded that the catalytic selectivity of PdNi equal with PdAu. Further, the stability of PdNi alloy was explored by calculating the binding and compared it with Pd, which leads to the conclusion that PdNi can be a good catalyst for H2O2 synthesis.