ABSTRACT
The novel Z-scheme heterojunction photocatalyst W18O49/CeO2 was prepared by hydrothermal synthesis. The photocatalytic properties of W18O49/CeO2 were evaluated by photocatalytic hydrogen evolution under visible light. The result shows that the 15 wt% W18O49/CeO2 composite has the best hydrogen production efficiency of about 0.2061 mmol g-1h-1, which was 1.93 times higher than that the obtained pure CeO2. The characterization results demonstrated that the existence of Z-scheme heterojunction structure at the contact interface of W18O49 and CeO2 was the origin of the enhanced photocatalytic performance for hydrogen evolution, which could greatly increase the accumulation of photo-generated electrons and the separation efficiency of charge carrier. In accordance with density functional theory (DFT) calculation, we further confirmed the formation of Z-scheme heterojunction structures. This work is anticipated to expand the ideas for modifying CeO2 semiconductor materials to improve the rate of photocatalytic hydrogen production.
ABSTRACT
OBJECTIVE: To explore the effect of silencing lumican on the invasion and migration of liver cancer cells. METHODS: Lumican was silenced by shRNA in liver cancer cells (HepG2 and MHCC97H). The mRNA levels of lumican were detected by qRT-PCR. Cell invasion was measured by Transwell. Cell migration was tested via wound healing. The protein levels of lumican,MMP-9,VEGF,ERK1,JNK,p-ERK1 and p-JNK were measured by Western blot. RESULTS: Liver cancer cells (HepG2 and MHCC97H) had higher levels of mRNA and protein of lumican compared with normal hepatocyte L02 (P<0.01). shRNA lowered the levels of mRNA and protein of lumican (P<0.01),and weakened the invasion and migration of cancer cells (P<0.01). The expressions of MMP-9 and VEGF decreased with the shRNA silence (P<0.01). shRNA also reduced the protein level of p-ERK1 and p-JNK (P<0.01). CONCLUSION: Silencing lumican by shRNA attenuates the invasion and migration of liver cancer cells via inhibiting the activation of ERK1/JNK pathway.
