Efficient Hydrogen Generation From Hydrolysis of Sodium Borohydride in Seawater Catalyzed by Polyoxometalate Supported on Activated Carbon

Abstract

Phosphotungstic acid (HPW) as a polyoxometalate was selected as the active component of the catalyst. The activated carbon supported different percentage of HPW catalysts were prepared by impregnation and were characterized by X-ray diffraction (XRD), nitrogen adsorption, Fourier transform infrared (FTIR), and scanning electron microscope (SEM). The results showed that the HPW retained the original Keggin structure after being supported on activated carbon, the specific surface of the HPW/C was much bigger than that of pure HPW. The catalytic performance of HPW/C in the hydrogen generation reaction by hydrolysis of sodium borohydride in seawater and in deionized water were studied. 2.5 wt.% HPW/C showed the fastest hydrolysis reaction rate and the biggest volume of hydrogen generated. As for hydrolysis of sodium borohydride, catalytic effect of HPW/C was better in seawater than in distilled water. HPW dispersed on activated carbon is a real promising catalytic system for the development of hydrogen generation by hydrolysis of NaBH 4 in seawater.

Bifunctional Noble-Metal-Free Catalyst for the Selective Aerobic Oxidation-Knoevenagel One-Pot Reaction: Encapsulation of Polyoxometalates into an Alkylamine-Modified MIL-101 Framework

“…To overcome this issue, immobilization of POMs into/onto porous solids is an effective strategy . During the last decades, various porous materials have been tested as support for the anchoring of POMs such as silica, ion-exchange resins, zeolites, activated carbon, and metal–organic frameworks (MOFs). − MOFs are interesting materials because of their unique characteristics including large surface area, long-range ordered porous structure, tunable pore size, and designable functionalities . The MIL-101, a chromium based MOF, has been documented as an outstanding platform to host POMs because of its high stability .…”

Performance Evaluation of KBH4 as Energy Carrier for Shipping Applications

“…The latter can either be stored in a separate tank or directly produced on board of the ship from the waters surrounding the vessel through reverse osmosis. While the use of such a reverse osmosis system has also been considered in a recently published feasibility study regarding the use of NaBH 4 as H 2 storage material for inland shipping applications [39], such costly water purification might not be necessary and, depending on the water quality, seawater could be directly used in the hydrolysis reaction as exemplarily demonstrated by Xi et al [40] in the case of NaBH 4 .…”