Publication: Melem Hydrate-Derived g-C3N4 Micro-Rods Coordinated with Cu2+: Why is Cu a superior cocatalyst compared to Ni and co?
Date
2024
Authors
Pandi K.
Kangeyan K.P.
Lakhera S.K.
Kiong T.S.
Bernaurdshaw N.
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier Ltd
Abstract
Graphitic carbon nitride (g-C?N?) holds significant promise for hydrogen production due to its visible-light activity, stability, and cost-effectiveness. However, it faces challenges related to high charge recombination and trapping, which ultimately hinders its photocatalytic efficiency. In this study, we address these limitations by first modifying g-C?N? nanosheets into rods through the formation of melem hydrate using an ultrasonication method. Subsequently, the melem hydrate is transformed into g-C?N? micro-rods (CNR). These CNR micro-rods are further coordinated with transition metals (Ni2?, Co2?, and Cu2?) via a hydrothermal process. Among these samples, the Cu-coordinated micro-rods exhibit the highest photocatalytic hydrogen production rate, achieving 4 mmol/g/h. This performance surpasses previously reported novel metal-coated g-C?N? materials. Notably, when compared to Ni and Co, the Cu-coordinated g-C?N? produces 2.8- and 3.6-times higher hydrogen, respectively. The enhanced performance is attributed to faster interfacial charge transfer kinetics between g-C?N? micro-rods and Cu, as evidenced by the highest kNT value of 0.81 ns?1 and kET value of 0.16 ns?1, measured using time-resolved photoluminescence spectroscopy. ? 2024 Elsevier Ltd
Description
Keywords
Carbon nitride , Charge transfer , Hydrates , Hydration , Hydrogen production , Nickel , Photoluminescence spectroscopy , Co catalysts , G-C3N4 , Graphitic carbon nitrides , H 2 production , High charges , Melem hydrate , Metal nitrate hydroxide , Microrods , Performance , Visible-light activity , Cost effectiveness