
In this study, titanium dioxide was loaded with chromium together with either platinum or rhodium in attempt to improve its photocatalytic activity for water splitting. Titanium dioxide was synthesized via a sol-gel method and the metals were loaded by incipient wetness impregnation technique. The amount of chromium added was varied between 0 to 1 % (w/w), while the amount of the second metals (either Pt or Rh) added was fixed at 1 % (w/w). The catalysts were characterized by UV-visible diffuse reflectance spectroscopy, X-ray diffraction (XRD), nitrogen physisorption, transmission electron microscopy (TEM), and photoluminescence. Addition of chromium up to 0.05 % (w/w) enhanced the photocatalytic activity because chromium prevented recombination of photogenerated electrons and holes in titanium dioxide. However, when the amount of chromium added exceeded 0.05% (w/w), the photocatalytic activity decreased owing to overtrapping of charge carriers by chromium. Photoluminescence measurement also suggested that titanium dioxide loaded with 0.05 % (w/w) Cr, of which photoluminescence signal was the lowest, had the slowest recombination of charge carriers. Addition of chromium together with platinum or rhodium further increased the photocatalytic activity for water splitting. The catalysts that possessed the highest activity were titanium dioxide that was loaded with 0.01 % (w/w) Cr and 1 % (w/w) Pt or Rh. The optimal loading of the metals could be explained by the similar reason above. Furthermore, a synergy between chromium and the other metal was observed. The amount of hydrogen gas produced from photocatalytic water splitting over titanium dioxide loaded with chromium together with either platinum or rhodium was greater than the sum of the amount of hydrogen gas produced from the reaction over either metal alone.
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 0 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Average | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |
