Open AccessAgglomeration of Pt nanoparticles on the g-C3N4 surface dominated by oriented attachment mechanism and way of inhibition
Author(s) -
Fengpo Yan,
Hao Zhang,
Yu Zhang,
Fugui Yang
Publication year - 2021
Publication title -
materials research express
Language(s) - English
Resource type - Journals
ISSN - 2053-1591
DOI - 10.1088/2053-1591/abfde6
Subject(s) - ostwald ripening , nanoparticle , materials science , coalescence (physics) , economies of agglomeration , photocatalysis , platinum , brownian motion , chemical engineering , nanotechnology , chemical physics , crystallography , catalysis , chemistry , organic chemistry , physics , quantum mechanics , engineering , astrobiology
0.3 mol% platinum loaded g-C 3 N 4 sample was prepared by photoreduction method to study the long-term stability of photocatalysts. For the first time, we have discovered the oriented attachment (OA) mechanism growth of Pt nanoparticles on g-C 3 N 4 solid surface, which is completely different from Ostwald ripening (OR) or particle migration and coalescence (PMC) that previously reported. The Pt nanoparticles perform Brownian motion on the surface of g-C 3 N 4 support under the collision of liquid molecules, then two or more nanoparticles attach together via the crystallographic orientation to construct larger ones. Al 2 O 3 film prepared by atomic layer depositon was introduced to inhibit the Brownian motion of Pt nanoparticles. It is found that as the increase of the Al 2 O 3 growth cycles, the photocatalytic hydrogen production of Pt/g-C 3 N 4 coated by Al 2 O 3 increase from 1.14 mmolg −1 h −1 to 2.08 mmolg −1 h −1 and then decrease to 1.4 mmolg −1 h −1 , and the apparent quantum efficiency (QE) also increase from 1.2% to 2.1% and then decrease to 1.4%. Meanwhile, the long-term stability of photocatalyst always increases. This work has revealed new pathway of photocatalytic nanoparticle growth on solid surface and proposed the method to prevent it.