Next frontier in photocatalytic hydrogen production through CdS heterojunctions
Aminul Islam, Abdul Malek, Md. Tarekul Islam, Farzana Yeasmin Nipa, Md. Obayed Raihan, Hasan Mahmud, Md. Elias Uddin, Mohd Lokman Ibrahim, G. Abdulkareem-Alsultan, Achintya Mondal, Md. Munjur Hasan, Md. Shad Salman, Khadiza Tul Kubra, Md. Nazmul Hasan, Md. Chanmiya Sheikh, Tetsuya Uchida, Adiba Islam Rasee, Ariyan Islam Rehan, Mrs Eti Awual, Mohammed Sohrab Hossain, R.M. Waliullah, Md. Rabiul Awual
Abstract
Photocatalytic hydrogen (H₂) generation via solar-powered water splitting represents a sustainable solution to the global energy crisis. Cadmium sulfide (CdS) has emerged as a promising semiconductor photocatalyst due to its tunable bandgap, high physicochemical stability, cost-effectiveness, and widespread availability. This review systematically examines recent advancements in CdS-based heterojunctions, categorized into CdS-metal (Schottky), CdS-semiconductor (p-n, Z-scheme, S-scheme), and CdS-carbon heterojunctions. Various strategies employed to enhance photocatalytic efficiency and stability are discussed, including band structure engineering, surface modification, and the incorporation of crosslinked architectures. A critical evaluation of the underlying photocatalytic mechanisms highlights recent efforts to improve charge separation and photostability under operational conditions. This review highlights the challenges and opportunities in advancing CdS-based photocatalysts and provides a direction for future research. The insights presented aim to accelerate the development of efficient and durable CdS-based photocatalysts for sustainable H₂ production.