Resolving two pathways of Al(OH)3 formation in hydrogen production from aluminum water reaction

Nur Fadhilah; Ruri Agung Wahyuono; Mahardika F. Rois; Doty Dewi Risanti

doi:10.1016/j.ijhydene.2025.05.311

Resolving two pathways of Al(OH)₃ formation in hydrogen production from aluminum water reaction

Nur Fadhilah
, Ruri Agung Wahyuono
, Mahardika F. Rois
, Doty Dewi Risanti^*

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

4 Citations (Scopus)

Abstract

Hydrogen production from aluminum-water reactions is often limited by the formation of a passive alumina (Al₂O₃) layer that hinders reactivity. In this study, a new system was developed by incorporating sodium aluminate (NaAlO₂) into a sodium hydroxide (NaOH) solution, with all parameters, room temperature and pH 13, kept constant to isolate the effect of solution composition. A maximum hydrogen yield of 77.4 % was achieved at a NaAlO₂ concentration of 0.5 M. In-situ electrochemical characterization showed that the reaction is governed by charge transfer across three stages: Al₂O₃ hydration, formation of Al(OH)₄⁻ accompanied by hydrogen release, and subsequent conversion to Al(OH)₃. The precipitation of Al(OH)₃ occurs in two phases gibbsite and bayerite through fast and slow reaction pathways, respectively. These pathways governed by solution stability, as a NaOH + NaAlO₂ mixture tends to destabilize Al(OH)₃ precipitation.

Original language	English
Pages (from-to)	112-120
Number of pages	9
Journal	International Journal of Hydrogen Energy
Volume	143
DOIs	https://doi.org/10.1016/j.ijhydene.2025.05.311
Publication status	Published - 1 Jul 2025

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

SDG 7 Affordable and Clean Energy

Keywords

Al(OH)
Aluminum
Electrochemical
Hydrogen
Water

Access to Document

10.1016/j.ijhydene.2025.05.311

Cite this

@article{4c45d6c6d28b4c2a899b9ac445737b12,

title = "Resolving two pathways of Al(OH)3 formation in hydrogen production from aluminum water reaction",

abstract = "Hydrogen production from aluminum-water reactions is often limited by the formation of a passive alumina (Al2O3) layer that hinders reactivity. In this study, a new system was developed by incorporating sodium aluminate (NaAlO2) into a sodium hydroxide (NaOH) solution, with all parameters, room temperature and pH 13, kept constant to isolate the effect of solution composition. A maximum hydrogen yield of 77.4 \% was achieved at a NaAlO2 concentration of 0.5 M. In-situ electrochemical characterization showed that the reaction is governed by charge transfer across three stages: Al2O3 hydration, formation of Al(OH)4− accompanied by hydrogen release, and subsequent conversion to Al(OH)3. The precipitation of Al(OH)3 occurs in two phases gibbsite and bayerite through fast and slow reaction pathways, respectively. These pathways governed by solution stability, as a NaOH + NaAlO2 mixture tends to destabilize Al(OH)3 precipitation.",

keywords = "Al(OH), Aluminum, Electrochemical, Hydrogen, Water",

author = "Nur Fadhilah and Wahyuono, \{Ruri Agung\} and Rois, \{Mahardika F.\} and Risanti, \{Doty Dewi\}",

note = "Publisher Copyright: {\textcopyright} 2025 Hydrogen Energy Publications LLC",

year = "2025",

month = jul,

day = "1",

doi = "10.1016/j.ijhydene.2025.05.311",

language = "English",

volume = "143",

pages = "112--120",

journal = "International Journal of Hydrogen Energy",

issn = "0360-3199",

publisher = "Elsevier Ltd.",

}

TY - JOUR

T1 - Resolving two pathways of Al(OH)3 formation in hydrogen production from aluminum water reaction

AU - Fadhilah, Nur

AU - Wahyuono, Ruri Agung

AU - Rois, Mahardika F.

AU - Risanti, Doty Dewi

PY - 2025/7/1

Y1 - 2025/7/1

N2 - Hydrogen production from aluminum-water reactions is often limited by the formation of a passive alumina (Al2O3) layer that hinders reactivity. In this study, a new system was developed by incorporating sodium aluminate (NaAlO2) into a sodium hydroxide (NaOH) solution, with all parameters, room temperature and pH 13, kept constant to isolate the effect of solution composition. A maximum hydrogen yield of 77.4 % was achieved at a NaAlO2 concentration of 0.5 M. In-situ electrochemical characterization showed that the reaction is governed by charge transfer across three stages: Al2O3 hydration, formation of Al(OH)4− accompanied by hydrogen release, and subsequent conversion to Al(OH)3. The precipitation of Al(OH)3 occurs in two phases gibbsite and bayerite through fast and slow reaction pathways, respectively. These pathways governed by solution stability, as a NaOH + NaAlO2 mixture tends to destabilize Al(OH)3 precipitation.

AB - Hydrogen production from aluminum-water reactions is often limited by the formation of a passive alumina (Al2O3) layer that hinders reactivity. In this study, a new system was developed by incorporating sodium aluminate (NaAlO2) into a sodium hydroxide (NaOH) solution, with all parameters, room temperature and pH 13, kept constant to isolate the effect of solution composition. A maximum hydrogen yield of 77.4 % was achieved at a NaAlO2 concentration of 0.5 M. In-situ electrochemical characterization showed that the reaction is governed by charge transfer across three stages: Al2O3 hydration, formation of Al(OH)4− accompanied by hydrogen release, and subsequent conversion to Al(OH)3. The precipitation of Al(OH)3 occurs in two phases gibbsite and bayerite through fast and slow reaction pathways, respectively. These pathways governed by solution stability, as a NaOH + NaAlO2 mixture tends to destabilize Al(OH)3 precipitation.

KW - Al(OH)

KW - Aluminum

KW - Electrochemical

KW - Hydrogen

KW - Water

UR - https://www.scopus.com/pages/publications/105007152864

U2 - 10.1016/j.ijhydene.2025.05.311

DO - 10.1016/j.ijhydene.2025.05.311

M3 - Article

AN - SCOPUS:105007152864

SN - 0360-3199

VL - 143

SP - 112

EP - 120

JO - International Journal of Hydrogen Energy

JF - International Journal of Hydrogen Energy

ER -