Conjugated Cationic Pp-x Formed on g-C₃N₄ for Photocatalyzed Water Splitting

Abstract

Polycationic Pp-x@g-C3N4 composite was synthesized through an in situ polymerization process of N-alkylpyridinium acetylenic alcohol bromide (p-x) above the surface of g-C3N4. The structure of p-0 and the Pp-x@g-C3N4 properties were checked by modern technologies. Photocatalytic tests of Pp-x@g-C3N4 in water splitting unveiled much better Pp-x@g-C3N4 hydrogen evolution activities by comparison with both g-C3N4 and Pp-0. The hydrogen production by Pp-0@g-C3N4 was 1654.5 μmol h–1 g–1, which is ∼26- and 22-fold greater in relation to what g-C3N4 and Pp-0 produced (62.7 and 75.0 μmol h–1 g–1, respectively), suggesting strong bilateral and synergistic interactions of g-C3N4 with Pp-0. Although the lengthening methylene chain in the polymers weakened the hydrogen generation ability of Pp-x@g-C3N4, the conjugated double bonds, solubilization, and dispersion of Pp-x polycationic surfactants made Pp-x@g-C3N4 superior to g-C3N4 in water splitting. Due to the readily available raw materials, a simple way of preparation (starting chemicals to p-0 to Pp-0@g-C3N4), high photocatalysis efficiency, light irritation stability, recyclable ability, and low toxicity, Pp-0@g-C3N4 is a good candidate for water splitting.

2D CeO2 and a Partially Phosphated 2D Ni-Based Metal–Organic Framework Formed an S-Scheme Heterojunction for Efficient Photocatalytic Hydrogen Evolution

“…Among the many approaches to the production of hydrogen, photocatalytic splitting of water is generally accepted as one of the most potential means. 7,8 Over the past couple of decades, a lot of materials have been exploited in photocatalytic water splitting to produce hydrogen, such as CdS, 9,10 g-C 3 N 4 , 11,12 ZnCdS, 13,14 etc. Nonetheless, these common catalysts still have some shortcomings such as the serious recombination and slow migration rate of carriers.…”

“…It is urgent to develop a clean and efficient means of hydrogen production. Among the many approaches to the production of hydrogen, photocatalytic splitting of water is generally accepted as one of the most potential means. , …”

Highly Conjugated Graphitic Carbon Nitride Nanofoam for Photocatalytic Hydrogen Evolution

“…As shown in Figure S14 and Table S4, the lifetime of the nanofoam (1.53 ns) is shorter than that of the bulk (2.24 ns) and nanosheet (1.64 ns). The shortest lifetime and weakest PL intensity of the g-CN nanofoam suggest the fastest charge separation in this sample. , We also made the three samples into photoanodes to measure their photocurrent density, which reflects the efficiency of charge separation. As shown in Figure d, the nanofoam delivers the highest photocurrent density (0.19 μA cm –2 ), significantly superior to that of the bulk (0.08 μA cm –2 ) and nanosheet (0.12 μA cm –2 ).…”

Photocatalytic Water‐Splitting by Organic Conjugated Polymers: Opportunities and Challenges

“…The results revealed that the lengthening of the methylene chain in the polymer decreased the hydrogen generation ability of Pp-x@ g-C 3 N 4 . [201] BiVO 4 is considered a promising candidate for the O 2 evolution as an OER photocatalyst but it is inefficient for overall water splitting because its conduction band is lower than the reduction potential of H 2 O. Even its OER activity also faces demerits of slow charge separation, finite visible light absorption, and insufficient charge-induced reaction efficiency.…”