Average Hydrogen Generation Research Articles

Efficient photocatalytic hydrogen production of Ni-Co layered double hydroxides (Ni-Co LDHs) anchored with reduced graphene oxide (rGO) hybrid composite

Using a suitable co-catalyst to boost photocatalytic H2 evolution from water splitting is crucial. Herein, we designed pristine NiCo-LDH and reduced graphene-oxide supported nickel-cobalt layered double hydroxide nanosheets (NiCo-LDH/rGO) as photocatalyst for the first time to evaluate the hydrogen production performance. Adding graphene has the potential to significantly increase electrical conductivity, and the supported NiCo-LDH has the potential to significantly reduce the likelihood of graphene self-aggregation. The effectiveness of its photocatalytic hydrogen generation was analyzed using a set of characterizations. The H2 evolution rates for pure rGO were 345.2 μmolh−1g−1, whereas those for Ni-Co LDH/rGO were 578.2 μmolh−1g−1. Average hydrogen generation per hour for the Ni-Co LDH/rGO composite material was 2032.1 μmolh−1g−1, which was 5.8 and 3.5 times that of rGO and Ni-Co LDH/rGO, respectively, NiCo-LDH@rGO's synergistic impact on the NiCo-LDH boosts the H2 generation pathway by increasing the catalyst's stability as well as performance by exposing active sites and speeding up electron transport. The produced nanocomposite shows excellent spatial charge separation and quicker electron transport across the conductive network of rGO, as shown by the photocurrent response test and photoluminescence (PL) spectra. The results of this study provide a fresh perspective on the practical use and synthesis of the inexpensive and effective NiCo-LDH/rGO, demonstrating the standard deviation of logical planning and preparation of high-performance photocatalysts.

Accurately measuring the hydrogen generation rate for hydrolysis of sodium borohydride on multiwalled carbon nanotubes/Co–B catalysts

Multiwalled carbon nanotubes supported cobalt–boron catalysts (Co–B/MWCNT) were developed via the chemical reduction of aqueous sodium borohydride with cobalt chloride for catalytic hydrolysis of alkaline NaBH 4 solution. The hydrogen generation (HG) rates were measured on an improved high-accuracy, low-cost and automatic HG rate measurement system based on the use of an electronic balance with high accuracy. The HG of Co–B/MWCNT catalyst was investigated as a function of heat treatment, solution temperature, Co–B loading and supporting materials. The catalyst was mesoporous structured and showed lower activation energy of 40.40 kJ mol −1 for the hydrolysis of NaBH 4. The Co–B/MWCNT catalyst was not only highly active to achieve the average HG rate of 5.1 l min −1 g −1 compared to 3.1 l min −1 g −1 on Co–B/C catalyst under the same conditions but also reasonably stable for the continuous hydrolysis of NaBH 4 solution.

Carbon-supported platinum catalysts for on-site hydrogen generation from NaBH 4 solution

A flexible hydrogen generation (HG) method based on catalytic hydrolysis of NaBH 4 solution is developed. Carbon-supported platinum (Pt/C) samples served as the catalysts, and the catalytic strategies for hydrolysis of NaBH 4 solution are analyzed via the studies on apparent morphology, catalytic activity, BET surface, and sustaining H 2 supply test. Pt/C catalysts are proved to be excellent accelerators, and Pt-loading plays an important role in the hydrogen generation reactions. For a reactor loaded with 100 mg 13.1% Pt/C catalyst, when 10% NaBH 4–5% NaOH solution is pumped into the reactor with a speed of 10 ml/min, it can achieve a maximum HG rate of 29.6 (l/min/g catalyst), and give sustaining H 2 supply for a proton exchange membrane fuel cell (PEMFC) with an average HG rate of 23.0 (l/min/g catalyst).