No abstract

No abstract

No abstract

In this work, a CoPi-decorated type II heterojunction composed of one-dimensional (1D) ZnO nanorod arrays (NRAs) coated with two-dimensional (2D) carbon nitride (g-C3N4) was successfully prepared and used as photoanode. CoPi has been speculated to be a mixture of amorphous compound and two cobalt-based compounds: Co3(PO3)6·14H2O and Co(H2PO2)2·6H2O. The advanced bi-functional CoPi acts like a shelter, effectively inhibiting the photocorrosion of CNNS/ZnO NRAs and providing a faster hole transfer channel. Synergistic effects at the interface of the heterojunction efficiently improve the separation of charge carriers from photoexcited g-C3N4 nanosheets to the ZnO nanorods. Photocurrent density is also greatly enhanced by loading CoPi on CNNS/ZnO NRAs heterojunction. The maximum photocurrent density (2.45 mA cm-2 at 1.23 V vs. RHE) generated from CoPi(10)-CNNS(600)/ZnO nanorods is about 10.2 times greater than that of pristine ZnO nanorods (0.24 mA cm-2 at 1.23 V vs. RHE) and 2.5 times higher than that of CNNS(800)/ZnO (0.95 mA cm-2 at 1.23 V vs. RHE). The further increase of photoelectrocatalytic performance may be attributed to CoPi relieving the charge accumulation at the semiconductor/electrolyte, which decreases the electron-hole recombination rate.

No abstract

No abstract

Recently, a series of novel thermoelectric (TE) materials have been rapidly screened out through high-throughput calculation; meanwhile, although this method improves the screening speed, it also reduces the accuracy of estimation. Therefore, further accurate analysis of the newly reported materials' electrical and thermal transport properties should be conducted to understand their microscopic transport mechanism. In this work, we investigate the TE transport properties of monolayer Hf 2 Cl 4 in which it has been figured out that there exists a high electronic fitness function (EFF) value for TE applications based on the first-principles approach by using density functional theory and the semiclassical Boltzmann transport equation. The TE parameters of monolayer Hf 2 Cl 4 , including thermal conductivity, Seebeck coefficient, electrical conductivity, and so on, are calculated to evaluate its figure of merit ZT at temperatures of 300, 500, and 700 K. It is found that these TE parameters are highly anisotropic between x-and y-directions, which is the critical factor for its excellent TE performance. The optimal figure of merit of 3.2 is achieved along the x-direction for hole doping at 700 K. Our study reveals that monolayer Hf 2 Cl 4 could be a suitable candidate for TE materials, and high-throughput calculation screening is effective for enhancing TE performance.

No abstract