用於pH通用析氫反應的二維多孔磷化鉬氮化物異質結納米片
作者:
小柯機器人發布時間:2020/12/19 16:03:10
黑龍江大學付宏剛團隊研製了用於pH通用析氫反應的二維多孔磷化鉬氮化物異質結納米片。 相關研究成果於2020年12月17日發表在《德國應用化學》。
鉬基催化劑的形貌和異質結工程是高效析氫反應的研究熱點,但如何同時實現這兩個目標仍然是一個挑戰。
該文中,研究人員展示了一種基於從聚乙二醇(PEG)介導組裝路線裂解2D[PMo12O40]3-三聚氰胺(PMo12-MA)納米片前驅體的基礎上合成二維(2D)多孔MoP/Mo2N異質結納米片的新策略。所製備的異質結構納米片厚度約為20nm,且具有豐富的孔隙(<5nm)。
這些結構特徵為提高HER活性提供了一些有利條件,包括理論計算所證實的異質結周圍良好的水分解動力學、二維納米片的大型可接近表面以及通過孔增強的質量傳輸能力。因此,2D多孔MoP/Mo2N異質結納米片表現出優異的HER活性,在鹼性、中性和酸性電解質中的過電位分別為89、91和89mV,電流密度分別達到10mA cm-2。特別是在中性介質中電流密度>55mA cm-2,在鹼性介質中電流密度>190mA cm-2時,其HER性能優於商用Pt/C。
該工作為二維多孔異質結構催化劑的製備提供了希望。
附:英文原文
Title: Two Dimensional Porous Molybdenum Phosphide/Nitride Heterojunction Nanosheets for pH‐Universal Hydrogen Evolution Reaction
Author: Honggang Fu, Ying Gu, Aiping Wu, Yanqing Jiao, Huiru Zheng, Xueqi Wang, Ying Xie, Lei Wang, Chungui Tian
Issue&Volume: 17 December 2020
Abstract: The morphology and heterojunction engineering of Mo‐based catalysts are intensively pursued for effective hydrogen evolution reaction (HER), but it remains a challenge to achieve the two targets simultaneously. Herein, we show a new strategy toward the synthesis of two‐dimensional (2D) porous MoP/Mo2N heterojunction nanosheets based on the pyrolysis of 2D [PMo12O40]3‐ ‐melamine (PMo12‐MA) nanosheet precursor from a polyethylene glycol (PEG)‐mediated assembly route. The heterostructure nanosheets is about 20 nm thick and has plentiful pores (< 5 nm). These structure features offer several advantages to promote the HER activity, including the favourable water dissociation kinetics around heterojunction as confirmed by theoretical calculations, large accessible surface of 2D nanosheets and enhanced mass‐transport ability by pores. Consequently, the 2D porous MoP/Mo2N heterojunction nanosheets exhibits excellent HER activity with low overpotentials of 89, 91 and 89 mV to achieve a current density of 10 mA cm‐2 in alkaline, neutral and acidic electrolytes, respectively. In particular, its HER performance is superior to the commercial Pt/C at a current density > 55 mA cm‐2 in neutral medium and >190 mA cm‐2 in alkaline medium. This work is promising for construction of 2D porous heterostructured catalysts.
DOI: 10.1002/anie.202016102
Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202016102