聚銦-銦-酞青懸掛于碳納米上，用于柔性鋅空氣電池

1成果簡介

　　氧還原反應（ORR）是鋅空氣電池等可再生能源技術的基石，但其緩慢的動力學特性及對貴金屬催化劑的依賴仍是關鍵瓶頸。本文，中國科學院福建物質結構研究所韓麗麗 研究員、溫州大學錢金杰 副教授、天津大學劉輝 英才教授等在《ADVANCED MATERALS》期刊發表名為“Covalent Dangling of
Poly-Indium-Phthalocyanine Over Carbon Nanopits as Superior Oxygen Reduction Catalyst for Flexible Zn-Air Battery”的論文，研究報道了一種創新催化劑——通過將聚銦酞菁共價懸掛于碳納米管缺陷區構建的碳納米管（InPPc/v-CNTs）。

　　該結構誘導軸向In-C配位，打破平面In-N4中心的對稱電子分布，強化了電子金屬-載體間相互作用。理論計算表明，這種扭曲的電子環境既增強了O2吸附/解離動力學，又降低了*OH脫附能壘，從而協同提升了ORR動力學。得益于定制電子結構與優化的金屬-載體配置，InPPc/v-CNTs展現出卓越的氧還原反應活性與穩定性：半波電位達0.90V vs RHE，動力學電流密度達42.9mA cm?2（遠超Pt/C基準值10倍以上）。此外，在水系鋅空氣電池中，該材料展現出270 mW cm?2的卓越功率密度，并在5 mA cm?2電流密度下保持高達865小時的放電穩定性。本研究通過將缺陷工程、電子不對稱性與大分子穩定化技術融合為統一框架，突破了傳統催化劑設計局限，為金屬酞菁類氧還原反應催化劑開創了全新范式。

2圖文導讀

圖1.a) Schematic synthesis of InPPc/v-CNTs. b) HRTEM images of CNTs and v-CNTs. c) TEM and d) HRTEM images of InPPc/v-CNTs. e,f) AC-HAADF-STEM images of InPPc/v-CNTs, the isolated In sites are highlighted by yellow circles, and inset in f) is the 3D atom-overlapping Gaussian-function fitting map of the isolated In site marked with a pink circle. g) HAADF image and elemental mappings of InPPc/v-CNTs.

圖2、(a) XRD patterns of InPPc, CNTs, v-CNTs, and InPPc/v-CNTs. (b) Raman spectra of CNTs, v-CNTs, and InPPc/v-CNTs. High-resolution (c) C 1s, (d) N 1s, and (e) In 3d XPS of InPPc, InPPc/CNTs, and InPPc/v-CNTs. (f) XANES, (g) Fourier-transformed EXAFS and (h) WT-EXAFS spectra of InPPc, InPPc/CNTs, InPPc/v-CNTs, and In foil at the In K-edge.

圖3、a) LSVs and b) Tafel plots of InPPC/v-CNTs, InPPc/CNTs, InPPc, v-CNTs, CNTs, and Pt/C at 1600 rpm in O2-saturated 0.1 M KOH electrolyte. c) Comparison of E1/2 and Tafel slopes between InPPc/v-CNTs and recently reported ORR catalysts. d) LSV polarization curves at different rotation speeds and corresponding K?L plots of InPPc/v-CNTs. e) Comparison of Jk and MA at 0.85 V among InPPC/v-CNTs, InPPc/CNTs, and Pt/C. f) Chronoamperometric curves and LSVs of InPPc/v-CNTs initially and after 5, 10, and 15k ADT CV cycles.

圖4、a) Schematic of the home-made aqueous rechargeable ZAB. b) OCV plots, c) discharge polarization and power density curves, d) specific discharge capacities at 10 mA cm2, and e) galvanostatic discharge curves at various current densities of the aqueous ZABs with InPPc/v-CNTs and Pt/C+RuO2 as cathodes, respectively. f) Application demonstration of charging a smartphone using the aqueous ZAB with the InPPc/v-CNTs cathode. g) Discharge–charge cycling at 5 mA cm?2 of the aqueous ZABs with InPPc/v-CNTs and Pt/C+RuO2 as cathodes, respectively. (h) OCV plots and i) discharge–charge cycling at 5 mA cm?2 of the quasi-solid-state rechargeable ZABs, insets show photographs of the quasi-solid-state ZABs in various states: flat (0°), bent (45°), bent (90°), bent (180°), and returned to flat (0°).

圖5、a) Adsorption configurations of *OOH, *O, and *OH intermediates on the InPPc/v-CNTs catalyst model. b) Projected DOS (PDOS) of the In–N4 center in different models. (c) Structural models with differential charge densities upon adsorption of O2 (yellow and cyan isosurfaces represent the electron accumulation and depletion, respectively). d) O2 adsorption energy and Bader charge analysis for InPPc/v-CNTs, InPPc/CNTs, and InPPc. e) ORR Gibbs free energy diagrams at 1.23 V for InPPc/v-CNTs, InPPc/CNTs, and InPPc. f) ORR Gibbs free energy diagrams at 1.23, 0.76, and 0 V for InPPc/v-CNTs.

3小結

　　綜上所述，我們通過將聚銦酞菁（InPPc）共價錨定于納米坑缺陷工程化碳納米管（v-CNTs）上，實現了氧還原催化領域的突破性進展。通過碳納米坑處的共價鍵合形成的軸向In–C配位，打破了平面In–N4中心的對稱電子分布，同時促進了強健的電子金屬-載體相互作用。密度泛函理論揭示，這種電子不對稱性優化了O2吸附/解離動力學，并降低了*OH中間體脫附的能量障礙，從而協同加速了四電子氧還原反應路徑。該InPPc/v-CNTs催化劑展現卓越性能：半波電位達0.90 V，動力學電流密度達42.9 mA cm?2（遠超基準Pt/C的10倍以上），并在30小時內保持優異穩定性。在液態鋅空氣電池中，該催化劑峰值功率密度達270 mW cm?2，并能穩定放電865小時，性能超越多數酞菁類及非貴金屬氧還原反應催化劑。此外，在準固態鋅空氣電池中，該材料展現出1.5伏的高開路電壓、92.0mW cm?2的峰值功率密度，以及優異的可重復充電性和可折疊性。通過整合缺陷工程、電子不對稱調制與高分子穩定化技術，本研究為鄰苯二甲酰亞胺類分子電催化劑在下一代可持續能源系統中的未來研究方向提供了新思路。

　　文獻
:https://doi.org/10.1002/adma.202522225

來源：材料分析與應用