強電解質載電子和質子載體的非耦合氧化還原催化制氫

強電解質載電子和質子載體的非耦合氧化還原催化制氫

作者：

小柯機器人

發布時間：2020/12/19 16:08:19

南方科技大學盧周廣團隊開發了一種強電解質載電子和質子載體的非耦合氧化還原催化制氫方法。 相關研究成果於2020年12月17日發表在《美國化學會志》。

電解水裂解法是一種有效的制氫方法。傳統的水電解槽同時在相鄰的電極室中產生氫氣和氧氣，這會降低純度、能源效率和系統的耐久性。

在不同的氧化還原電化學基礎上，研究人員開發了一種在鹼性溶液中使電極的析氫反應（HER）和析氧反應（OER）從電極分離到兩個空間分離催化劑床反應器的系統。通過一對閉合的電化學-化學循環，系統分別在Pt/Ni（OH）2和NiFe（OH）2催化劑上對7,8-二羥基-2-吩嗪磺酸（DHPS）和鐵氰化物介導的HER和OER進行反應。

在電流密度高達100mA/cm2的情況下，已實現近單位法拉第效率和持續產氫。從計算和實驗兩方面詳細考察了DHPS作為強電解質載電子和質子載體的優良的反應動力學，特別是其反應機理。

研究人員預計該文中演示的系統將提供一個有趣的替代傳統水電解制氫的策略。

附：英文原文

Title: Decoupled Redox Catalytic Hydrogen Production with a Robust Electrolyte-Borne Electron and Proton Carrier

Author: Feifei Zhang, Hang Zhang, Manohar Salla, Ning Qin, Mengqi Gao, Ya Ji, Shiqiang Huang, Sisi Wu, Ruifeng Zhang, Zhouguang Lu, Qing Wang

Issue&Volume: December 17, 2020

Abstract: Electrolytic water splitting is an effective approach for H2 mass production. A conventional water electrolyzer concurrently generates H2 and O2 in neighboring electrode compartments separated by a membrane, which brings about compromised purity, energy efficiency, and system durability. On the basis of distinct redox electrochemistry, here, we report a system that enables the decoupling of both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) from the electrodes to two spatially separated catalyst bed reactors in alkaline solutions. Through a pair of close-loop electrochemical–chemical cycles, the system operates upon 7,8-dihydroxy-2-phenazinesulfonic acid (DHPS) and ferricyanide-mediated HER and OER, respectively, on Pt/Ni(OH)2 and NiFe(OH)2 catalysts. Near unity faradaic efficiency and sustained production of hydrogen has been demonstrated at a current density up to 100 mA/cm2. The superior reaction kinetics, particularly the HER reaction mechanism of DHPS as a robust electrolyte-borne electron and proton carriers, were scrutinized both computationally and experimentally. We anticipate the system demonstrated here would provide an intriguing alternative to the conventional water electrolytic hydrogen production.

DOI: 10.1021/jacs.0c09510

Source: https://pubs.acs.org/doi/10.1021/jacs.0c09510