Controllable Synthesis of ZnO Nanorod-nanosheets Hierarchical Nanostructure on a Stainless Steel Mesh Via A Facile Hydrothermal Growth

Abstract

Abstract. ZnO nanorods-nanosheets (NR-NS) hierarchical nanostructure consisted of long nanorod and thin nanosheet branches have been built on a stainless steel mesh via a two-step hydrothermal growth process. The related structures and morphologies of the as-prepared products were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The XRD results confirmed that the obtained samples were wurtzite hexagonal structured ZnO. The FE-SEM observations showed that the smooth surfaces of nanorods were covered by nanosheets, resulting in the enhancement of internal surface area. It was found that trisodium citrate played a crucial role in the formation of ZnO NR-NS hierarchical nanostructures, and accordingly, the rational growth mechanism was suggested.

High‐Efficiency Dye‐Sensitized Solar Cells Based on a ZnO Nanorod/ Nanosheet Hierarchical Structure

“…Currently, reports in applying the two‐step hydrothermal synthesis method to prepare hierarchically structured films of ZnO NRs/NSs, as well as the application of such films to the DSSCs, are relatively rare. The second step of the hydrothermal synthesis method in existing reports all used aqueous Zn(NO 3 ) 2 ⋅6 H 2 O‐C 6 H 2 N 4 ‐C 6 H 5 Na 3 ⋅2 H 2 O, and only a few ZnO NSs with small dimensions were acquired . Here, the hierarchically structured films of ZnO NRs/NSs are prepared using the two‐step hydrothermal synthesis process, and the second hydrothermal synthesis step is to immerse the ZnO NRs into an aqueous solution of Zn(NO 3 ) 2 ⋅6 H 2 O‐CO(NH 2 ) 2 .…”

“…Currently,r eports in applying the two-steph ydrothermal synthesism ethod to prepare hierarchically structured films of ZnO NRs/NSs,a sw ell as the application of such films to the DSSCs,a re relatively rare.T he second step of the hydrothermal synthesis methodinexisting reports all used aqueous Zn(NO 3 ) 2 ·6 H 2 O-C 6 H 2 N 4 -C 6 H 5 Na 3 ·2 H 2 O, and only af ew ZnO NSs with small dimensionsw ere acquired. [23][24][25] Here, the hierarchically structured films of ZnO NRs/NSs are prepared using the two-step hydrothermal synthesis process, and the second hydrothermal synthesis step is to immerse the ZnO NRsi nto an aqueous solutiono fZ n(NO 3 ) 2 ·6 H 2 O-CO(NH 2 ) 2 .T he ZnO NSs obtainedi nt he secondh ydrothermal step had asingle crystalline structure.T he ZnO NSs consist of ZnO NPs with aparticle size of around 20 nm, and micropores with an aperture of 10 nm are found between particles.T he results show the obtained hierarchically structured films of ZnO NRs/NSs had al arge specific surface area and few grain boundaries,a nd the PCE of the DSSCs reached 4.59 %. To the best of the authors knowledge,t his is the first reporto ft his kind of hierarchically structured films made of ultralong ZnO NRs and poroussingle-crystalline ZnO NSs.…”