Preparation method of composite proton exchange membrane

Abstract

The invention discloses a preparation method of a composite proton exchange membrane, comprising the following steps of: sulfonating, preparing a sulfonated polyether ether ketone solution; preparing polyaniline filter liquid, preparing membrane preparing liquid, casting to form a membrane, and the like. The composite membrane is prepared by using SPEEK (sulfonated polyether ether ketone) as a basal body and PANI (Polyaniline) and HPA (Heteropoly acid) as dopants, a material source is wide and does not need to be imported, a preparation process is simple, and used instruments are simple, thereby the cost of the membrane is reduced. A hydrogen bond formed by PANI and SPEEK is used for avoiding the swelling of the SPEEK and reducing methanol penetration, and the proton conductivity of the composite membrane is improved by the HPA. By changing the composition and the ratio between an alkaline polymer and a proton conductor, the novel PEM (proton exchange membrane) reaches optimum balance among high proton conductivity, low methanol penetration and low HPA dropout rate, the proton conductivity reaches 10-2S / cm, the methanol penetration rate of the composite proton exchange membrane is a half lower than that of an Nafion 117 membrane, and the HPA wastage rate does not reach 5 percent.

Description

Technical field: [0001] The invention relates to a preparation method of a proton exchange membrane. Background technique: [0002] Proton exchange membrane (PEM) is one of the core components of proton exchange membrane fuel cell (PEMFC) and direct alcohol fuel cell (including DMFC and DEFC), its role is: (1) Separate the anode and cathode to prevent the direct mixing of fuel and air (oxygen) for chemical reactions; (2) conduct protons, the higher the proton conductivity, the smaller the internal resistance of the membrane, and the higher the efficiency of the fuel cell; (3) The electrical insulator, The electrons are prevented from conducting in the membrane, and the electrons flow from the anode to the cathode through the external line, generating an external current for people to use. Generally, PEM materials for fuel cells must meet the following requirements: (1) low cost; (2) high proton conductivity; (3) good mechanical strength (anti-swelling) and dimensional stabi...

AI Technical Summary

Problems solved by technology

But it still has some disadvantages: (1) It has high requirements on temperature and water content, and its optimum working temperature is 70°C to 90°C. If the temperature exceeds this temperature, its water content will drop sharply, and the proton conductivity will drop rapidly; ( 2) The selectivity to methanol and water is poor, and the alcohol resistance performance is poor. More than 40% of methanol will pass through the membrane during use, which reduces battery performance and fuel utilization, and is not suitable for use as a direct methanol fuel cell ( Directmethanol fuel cell, DMFC) PEM

However, the process is relatively complicated, and the influence of N, N'-carbonyldiimidazole and coupling agent on the membrane performance is not considered.