| 摘要: | 利用可再生能源電解水產氫是一種理想且環保的氫能獲取途徑。目前主要有三種低溫電解水產氫技術：鹼性電解水（Alkaline Water Electrolyzer, AWE）可使用非貴金屬觸媒，但反應效率較低、能耗較高；質子交換膜電解水（Proton Exchange Membrane Water Electrolyzer, PEMWE）反應快速、能耗低，但需使用昂貴的貴金屬觸媒；而陰離子交換膜電解水（Anion Exchange Membrane Water Electrolyzer, AEMWE）技術則被視為一種新興的有前景方向，它兼具AWE和PEMWE的優點，可在獲得高電流密度和低能耗的同時，使用廉價且儲量豐富的非貴金屬觸媒，有望大幅降低產氫成本，因此備受關注。
本文主要研究用於AEMWE所需的陽極觸媒，文獻報導過渡金屬鐵和鎳是具有良好催化性能的元素，為了增加催化活性或是穩定性，我們在製備過程中添加了鈷或錳，以水熱法在基板上製成FeNiCo或FeNiMn觸媒。經過參數的調控，成功製備出高效能的析氧反應電催化材料，並將其組裝成膜電極，進行性能測試。首先採用水熱合成法，成功製備出非貴金屬自支撐陽極觸媒電極。將所製備的FeNiCo/Ni mesh電化學測試，該觸媒僅需298 mV的過電位，反應出其一定的催化能力。隨後將此應用於AEMWE整體裝置的組裝。在200 mA/cm2的電流密度下，所需的電解電壓僅為1.69 V。經過200小時的長期測試，當工作電壓為2 V時，電流密度僅增加13 mA/cm2，展現了穩定性。後續也進行以鎳網基板作為陰極，搭配自製水熱合成的FeNiCo/Ni mesh陽極，組裝全非貴金屬的AEMWE。在工作電壓為2 V的條件下，該電流密度可達507 mA/cm2，顯示具備在電解水產氫領域中一定的應用潛力。
;Utilizing renewable energy for water electrolysis to produce hydrogen is an ideal and environmentally friendly approach to obtain hydrogen energy. Currently, there are three main low-temperature water electrolysis technologies for hydrogen production: alkaline water electrolysis(AWE) can use non-precious metal catalysts, but has relatively low reaction efficiency and high energy consumption; proton exchange membrane water electrolysis(PEMWE) has fast reaction and low energy consumption, but requires expensive precious metal catalysts; while anion exchange membrane water electrolysis(AEMWE) is considered an emerging and promising direction, combining the advantages of AWE and PEMWE. It can achieve high current density and low energy consumption while using inexpensive and abundant non-precious metal catalysts, potentially significantly reducing the cost of hydrogen production, and thus receiving increasing attention.
This work mainly investigates the anode catalysts required for AEMWE. Previous literature reports that transition metals iron and nickel possess good catalytic performance, and to enhance the catalytic activity or stability, we added cobalt or manganese elements during the preparation process, and used a hydrothermal method to synthesize FeNiCo or FeNiMn catalysts on substrates. Through such tuning, highly efficient oxygen evolution reaction(OER) electrocatalytic materials were successfully prepared and assembled into membrane electrodes for performance testing of AEMWE.
First, a non-precious metal self-supported anode catalyst was successfully prepared using the hydrothermal synthesis method. When the prepared FeNiCo/Ni mesh anode catalyst was placed in 1 M KOH for OER electrochemical testing, it only required an overpotential of 298 mV, reflecting its certain OER catalytic ability. Subsequently, it was applied to the assembly of the overall AEMWE device. With the FeNiCo/Ni mesh as the anode and commercial Pt/CP as the cathode, at a current density of 200 mA/cm2, the required electrolysis voltage was only 1.69 V, and after 200 hours of long-term stability testing, when the operating voltage was 2 V, the current density only increased by 13 mA/cm2, demonstrating its stability. Additionally, an all-non-precious metal AEMWE was assembled using a nickel substrate as the cathode and the self-prepared hydrothermally synthesized FeNiCo/Ni mesh as the anode. Under an operating voltage of 2 V, the current density could reach 507 mA/cm2, showing potential for application in the field of water electrolysis for hydrogen production. |
