From charge transfer to sustainability: A multifaceted DFT approach to ionic liquid design

IF 5.9 3区材料科学 Q2 CHEMISTRY, PHYSICAL

FlatChem Pub Date : 2025-06-11 DOI:10.1016/j.flatc.2025.100899

Danish Ali , Muhammad Arif Ali , Afifa Yousuf , Hong-Liang Xu

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引用次数: 0

Abstract

This study employs density functional theory (DFT) at the M06-2×/6–31 + g(d,p) level to investigate the structural, electronic, and thermodynamic properties of ammonium ([AM]⁺), phosphonium ([PH]⁺), and sulfonium ([SU]⁺) ionic liquids (ILs) paired with halide ([Br]⁻, [Cl]⁻, [F]⁻) and sulfonate ([CF₃SO₃]⁻, [CH₃SO₃]⁻) anions. Frontier molecular orbital (FMO) analysis reveals [PH]⁺[Br]⁻ as the most reactive IL pair with the smallest energy gap (5.57 eV), while [SU]⁺[CF₃SO₃]⁻ exhibits the highest stability (8.58 eV). Potential energy surface (PES) scans demonstrate substantial rotational energy barriers, confirming strong cation-anion interactions. Natural bond orbital (NBO) analysis shows [PH]⁺[Br]⁻ has the highest binding energy (−530.55 kcal/mol), supported by energy decomposition analysis (EDA) indicating dominant orbital stabilization. Net population analysis (NPA) reveals significant charge transfer, with [PH]⁺[Br]⁻ displaying optimal electrostatic complementarity. Thermodynamic calculations confirm the spontaneous formation of all IL pairs. Independent gradient model based on Hirshfeld (IGMH) and quantum theory of atoms in molecules (AIM) analyses validate non-covalent interactions and thermal stability. The [PH]⁺[Br]⁻ pair exhibits exceptional orbital stabilization (E⁽²⁾ = 10.73 kcal/mol) and low rotational barriers, making it a promising candidate for catalytic applications. This comprehensive computational study provides fundamental insights into IL design, highlighting the interplay between electronic structure, charge distribution, and intermolecular interactions. The results establish a framework for developing stable, reactive ILs for green chemistry and energy applications, with [PH]⁺[Br]⁻ emerging as a particularly efficient system.

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从电荷转移到可持续性：离子液体设计的多方面DFT方法

本研究采用m06 - 2x / 6-31 + g（d,p）水平的密度泛函理论（DFT）来研究铵离子液体（[AM]+）、磷离子液体（[PH]+）和磺离子液体（[SU]+）与卤化物离子（[Br]−、[Cl]−、[F]−）和磺酸盐离子（[CF₃SO₃]−、[CH₃SO₃]−）的结构、电子和热力学性质。前沿分子轨道（FMO）分析表明，[PH]+[Br]−反应性最强，能隙最小（5.57 eV），而[SU]+[CF₃SO₃]−稳定性最高（8.58 eV）。势能表面（PES）扫描显示了大量的旋转能垒，证实了强的阳离子-阴离子相互作用。自然键轨道（NBO）分析表明，[PH]+[Br]−具有最高的结合能（- 530.55 kcal/mol），能量分解分析（EDA）支持这一结论。净居群分析（NPA）显示了显著的电荷转移，[PH]+[Br]−表现出最佳的静电互补性。热力学计算证实了所有IL对的自发形成。基于Hirshfeld （IGMH）和分子中原子量子理论（AIM）的独立梯度模型分析验证了非共价相互作用和热稳定性。[PH]+[Br]−对具有优异的轨道稳定性（E(2) = 10.73 kcal/mol）和较低的旋转势垒，是催化应用的理想选择。这项全面的计算研究为IL设计提供了基本的见解，突出了电子结构，电荷分布和分子间相互作用之间的相互作用。研究结果为开发用于绿色化学和能源应用的稳定、反应性il建立了框架，其中[PH]+[Br]−成为一种特别高效的体系。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

FlatChem Multiple-

CiteScore

8.40

自引率

6.50%

发文量

104

审稿时长

26 days

期刊介绍： FlatChem - Chemistry of Flat Materials, a new voice in the community, publishes original and significant, cutting-edge research related to the chemistry of graphene and related 2D & layered materials. The overall aim of the journal is to combine the chemistry and applications of these materials, where the submission of communications, full papers, and concepts should contain chemistry in a materials context, which can be both experimental and/or theoretical. In addition to original research articles, FlatChem also offers reviews, minireviews, highlights and perspectives on the future of this research area with the scientific leaders in fields related to Flat Materials. Topics of interest include, but are not limited to, the following: -Design, synthesis, applications and investigation of graphene, graphene related materials and other 2D & layered materials (for example Silicene, Germanene, Phosphorene, MXenes, Boron nitride, Transition metal dichalcogenides) -Characterization of these materials using all forms of spectroscopy and microscopy techniques -Chemical modification or functionalization and dispersion of these materials, as well as interactions with other materials -Exploring the surface chemistry of these materials for applications in: Sensors or detectors in electrochemical/Lab on a Chip devices, Composite materials, Membranes, Environment technology, Catalysis for energy storage and conversion (for example fuel cells, supercapacitors, batteries, hydrogen storage), Biomedical technology (drug delivery, biosensing, bioimaging)