In situ sulfuration synthesis of heterostructure MoS₂–Mo₂C@C for boosting the photocatalytic H₂ production activity of TiO₂

Abstract

Hexagonal molybdenum carbide (Mo2C) with a similar structure to Pt as a cocatalyst has been extensively researched in the field of photocatalytic hydrogen evolution. However, owing to its limited hydrogen-evolution...

Crystalline Intramolecular Ternary Carbon Nitride Homojunction for Photocatalytic Hydrogen Evolution

“…With the rapid development of photocatalysts in recent years, photocatalysis for hydrogen evolution has become a promising strategy to solve environmental problems and energy consumption. − As a metal-free photocatalyst material rich in C and N elements, graphitic carbon nitride (g-C 3 N 4 ) has caused widespread concern owing to its excellent physical and chemical stability, moderate band structure, adjustable electronic structure, easy accessibility, and nontoxicity. − However, the pristine block C 3 N 4 is severely limited in its application in photocatalytic water splitting because of its defects, including low mobility of photoelectron–hole pairs and fast recombination rate. , Therefore, various strategies have been proposed, such as surface engineering, , construction of heterojunctions, − improving the crystalline degree, , as well as increasing the surface area . Among them, enhancing the crystallization degree of the pristine C 3 N 4 is an effective method to increase the photocatalytic efficiency because the highly crystallized C 3 N 4 can advance the separation and migration of charge carriers because of the removal of a large number of hydrogen bonds and amino groups from the pristine C 3 N 4 . − In particular, heptazine carbon nitride (HCN) with heptazine molecules as structural units was obtained using the molten salt method.…”

Improved H-adsorption ability of Cu in CuNi alloy nanodots toward the efficient photocatalytic H2-evolution activity of TiO2

“…11C, the CuNi-rGO/TiO 2 photocatalyst attains the smallest arc radius, further suggesting the outstanding transfer efficiency of photoinduced carriers in the CuNi-rGO/TiO 2 sample. 51–53 Therefore, it is rational to conclude that the introduction of Ni in Cu to form CuNi alloy nanodots can distinctly improve the H-adsorption ability of Cu and promote the photocatalytic H 2 -evolution activity of CuNi-rGO/TiO 2 . More importantly, typical semiconductor materials (such as anatase TiO 2 and CdS) are also modified by CuNi-rGO using a photodeposition method similar to CuNi-rGO/TiO 2 , and the photocatalytic H 2 -evolution activities of CuNi-rGO/anatase TiO 2 and CuNi-rGO/CdS photocatalysts are notably higher than that of pure anatase TiO 2 and CdS, respectively (Fig.…”

Optimizing Oxygen and Intermediate HOO* Adsorption of Cu–Pd Alloy Cocatalyst for Boosting Photocatalytic H2O2 Production of BiVO4

“…Obviously, the Cu/BiVO 4 photocatalyst displays the highest photocurrent density compared with other samples, further exhibiting the excellent transfer efficiency of Cu/BiVO 4 , which also suggests that low Schottky barrier height between BiVO 4 and Cu accelerates the interfacial transfer of photogenerated carriers. [21,63,64] However, during illumination, the photogenerated electrons of BiVO 4 are difficult to transfer to Pd, so the photocurrent density of Pd/BiVO 4 is small and not stable. When the second metal Cu is introduced to form Cu-Pd alloy, the photocurrent of the Cu-Pd/BiVO 4 (5:1) sample is significantly improved.…”