▎ 摘　　要

In this study, a new core-shell heterostructure of multiwalled carbon nanotube@reduced graphene oxide nanoribbon (MWCNT@rGONR) was prepared by modified microwave-assisted synthesis step and a chemical reduction. The core-shell heterostructure of MWCNT@rGONR was used as the catalytic film of the counter electrode (CE) of a dye-sensitized solar cell (DSSC). The chemical state and the degree of defects on the surface of MWCNT@rGONR were investigated by X-ray photoelectron spectroscopy (XPS) and Raman spectra, respectively. Transmission electron microscopy (TEM) image of the film of MWCNT@rGONR shows graphene sheet, covering on a MWCNT, indicating a core of the carbon nanotube and its shell of graphene. Photocurrent density voltage characteristics of the DSSCs, using commercial graphene nanopowder (GNP), MWCNT, and MWCNT@rGONR as the CE materials were obtained at 100 mW cm(-2). Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to study the electrocatalytic abilities of the films of GNP, MWCNT, and MWCNT@rGONR. Owing to the excellent electrocatalytic ability of the MWCNT@rGONR for the reduction of triiodide ions (I-3(-)), a solar-to-electricity conversion efficiency (eta) of 6.9196 was achieved for its DSSC, using our synthesized YD2-o-C8 porphyrin dye, while efficiencies of 4.48% and 5.93% were obtained for the DSSCs with the bare GNP and pristine MWCNT, respectively. The performance of the cell with the MWCNT@rGONR is comparable to that of the cell with a sputtered Pt (s-Pt) on its CE (7.26%).