Paper-based Two-dimensional Tungsten Trioxide Nanosheets

In recent years, flexible perovskite solar cells have attracted much attention, and the flexible substrates used have a great impact on the performance of devices. At present, the commonly used flexible substrates of polyethylene terephthalate (PET) and metal foil can not meet the demand. It is urgent to find a cheap and abundant new flexible substitutes.

Tungsten trioxide is an n-type semiconductor material with a bandgap of 2.6 eV and an orthogonal octahedron structure. It is widely used in optoelectronic devices, electrochromic and photoelectrochemical immunoassay sensors.

Some scholars are researching a paper-based two-dimensional tungsten trioxide nanosheet. In the process, surfactants or templates are not needed. The purpose of preparing two-dimensional tungsten trioxide nanosheets is simple, fast, low-cost and environmentally friendly. The research process includes:

A.Functionalized paper base: Cellulose paper is selected as the base, the size of which is cut to 4.0 cm and the width of which is 1.0 cm. Silver paste is printed on the surface of cellulose paper to make it conductive and smooth.

B.Deposition of nano-tungsten trioxide seed layer: a certain thickness of nano-tungsten trioxide seed layer was deposited on the surface of paper substrate obtained in step a by pulsed laser deposition.

C.Prepare tungsten trioxide precursor solution: weigh a certain amount of sodium tungstate and dissolve it in ultra-pure water. After magnetic stirring for 5 minutes, add a certain volume of hydrochloric acid, then weigh a certain amount of ammonium oxalate into the solution, and magnetic stirring for 30 minutes.

D.growing a two-dimensional tungsten trioxide nanosheet: transferring the uniformly stirred precursor solution in step C to a stainless steel reactor lining the polytetrafluoroethylene, and the paper substrate processed in step b is electrically conductive downward. The form is placed in the inner liner, the reaction kettle is closed and sealed, and placed in a preheated oven for reaction. After the reaction is completed, the reaction vessel is taken out and naturally cooled to room temperature to obtain a paper-based two-dimensional tungsten trioxide nanosheet material.

In this study, paper-based two-dimensional tungsten trioxide nanosheets were prepared for the first time on the basis of paper, which is rich in raw materials, cheap and easy to obtain, flexible and foldable. This method is simple to operate, low cost, no dispersant or surfactant is used in the process, and no pollution to the environment. The prepared paper-based two-dimensional tungsten trioxide material can be used as the electronic transport layer of flexible perovskite solar cells and has broad application prospects in flexible photoelectric immunosensors.

• < Prev
• Next >