Thermodynamics, kinetics and reaction mechanism of hydrogen production from a novel Al alloy/NaCl/g-C3N4 composite by low temperature hydrolysis

Real-time hydrogen production at low temperature can effectively solve the problem of hydrogen storage and transportation in cold area and plateau region. In this study, a novel Al alloy/NaCl/g-C3N4 composite with enhanced low temperature reactivity for hydrogen production has been synthesized by mechanical ball milling method. The feasibility of Al-water reaction at the temperature of 253.15-373.15 K was firstly proved by thermodynamic calculation. The hydrogen generation performance was studied in tap water at 298.15 K and 23 wt% NaCl aqueous solution at low temperature of 253.15-273.15 K. The results indicated that the addition of g-C3N4 can effectively promoted the hydrolysis of activated Al composites. Hydrogen yield of Al alloy/NaCl/g-C3N4 composite with 1 g of g-C3N4 addition reached 1006 mL.gAl(-1) and the induction time of reaction was 90 s at 253.15 K, while that of Al alloy was only 230 mL.gAl(-1) and 1120s respectively. It was supposed that the addition of g-C3N4 effectively reduced the size of NaCl particles and promoted their uniform distribution in Al matrix and more cracks were generated. The kinetics and reaction mechanism using Al alloy/NaCl/g-C3N4 composite were discussed. This study provides a new idea for the synthesis of Al composites with high reactivity at low temperature. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The study focused on enhancing hydrogen production reactivity at low temperature by synthesizing a novel Al alloy/NaCl/g-C3N4 composite, which showed improved performance at 253.15 K. The addition of g-C3N4 effectively promoted the hydrolysis of activated Al composites, leading to increased hydrogen yield.