Photocatalytic Generation of Hydrogen from a Non-carbon Source, Ammonia in Aqueous Solutions

Laura Clarizia; Abdulaziz M. Alanazi; Changseok Han

Abstract

This review investigates hydrogen production via photocatalysis using ammonia, a carbon-free source potentially present in wastewater. Photocatalysis offers low energy requirements and high conversion efficiency compared to electrocatalysis, thermocatalysis, and plasma catalysis. However, challenges such as complex material synthesis, low stability, spectral inefficiency, high costs, and integration barriers hinder industrial scalability. The review addresses thermodynamic requirements, reaction mechanisms, and the role of pH in optimizing photocatalysis. By leveraging ammonia’s potential and advancing photocatalyst development, this study provides a framework for scalable, sustainable hydrogen production and simultaneous ammonia decomposition, paving the way for innovative energy solutions and wastewater management.

Funding source: CH acknowledged the support by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. RS2025-00461931), Grant PID2023-152563OB-I00 funded by MCIN/ AEI /10.13039/501100011033 and FEDER, UE, and the research support provided through a Fulbright Visiting Scholar Award from the KoreanAmerican Educational Commission, funded by the U.S. and Korean Governments. LC acknowledged the support by the financial support by the project MUR-PRIN 2022 PNRR P2022AK3CA, “Sustainable rEmedial Approach FoR pOlluted mariNe sedimenTs” (SEAFRONT), funded by the European Union — Next Generation EU (NGEU). This work was funded by the Sustainable Energy Technologies Center at King Saud University, Riyadh, Saudi Arabia.

Keywords: Hydrogen Production ; Photocatalysis

Related subjects: Production & Supply Chain

Countries: Italy ; Korea, Republic of ; Saudi Arabia