Ammonia (NH₃) pollution poses a serious environmental threat. Ionic liquids (ILs) are regarded as potential solvents to treat NH₃-containing gases because of their unique properties, including tunable structures and high affinity for NH₃ molecules. In order to achieve an efficient and reversible absorption of NH₃, a series of protic ionic liquids (PILs) with multiple active sites were designed by introducing acidic protons, as well as the Li⁺ ion into ILs, resulting in PILs with two acidic protons on cations ([2-Mim][NTf₂] and [Im][NTf₂]), as well as dual functionalised PILs with a Lewis acidic Li⁺-based anion and acidic protons on cations, namely, [2-Mim][Li(NTf₂)₂] and [Eim][Li(NTf₂)₂]. The NH₃ absorption capacity of [Im][NTf₂] was found to be 3.46 mol NH₃/mol IL, which is the highest among the NH₃ absorption capacities of all known nonmetallic ILs, and is ascribed to the hydrogen bonding interactions between the NH₃ and PIL molecules. Furthermore, [2-Mim][Li(NTf₂)₂] exhibited the highest NH₃ absorption capacity, with a value of 7.01 mol NH₃/mol IL, which is about 30 times higher than that of conventional ILs. The superior NH₃ absorption performance of the dual functionalised PILs is attributed to the combination of hydrogen bonding interactions between the protons and the NH₃ molecules, and the formation of coordination complexes between the Li⁺-based anion and the NH₃ molecules. Moreover, the ILs studied here exhibited excellent recyclability, indicating a great potential for their use in applications involving efficient and reversible NH₃ absorption from NH₃-containing industrial gases.

氨（NH ₃）污染构成严重的环境威胁。离子液体（ILs）由于其独特的特性（包括可调结构和对NH ₃分子的高亲和力）而被视为处理含NH ₃气体的潜在溶剂。为了实现NH ₃的有效和可逆吸收，通过将酸性质子以及Li ⁺离子引入IL，设计了具有多个活性位的一系列质子离子液体（PIL），生成了带有两个酸性质子的PIL。阳离子（[2-Mim] [NTf ₂ ]和[Im] [NTf ₂ ]）以及具有路易斯酸性Li ^+的双官能化PIL的阳离子和酸性质子，即[2-Mim] [Li（NTf ₂）₂ ]和[Eim] [Li（NTf ₂）₂ ]。发现[Im] [NTf ₂ ]的NH ₃吸收容量为3.46 mol NH ₃ / mol IL，在所有已知的非金属离子液体的NH ₃吸收容量中是最高的，并且归因于它们之间的氢键相互作用NH ₃和PIL分子。此外，[2-Mim] [Li（NTf ₂）₂ ]表现出最高的NH ₃吸收容量，值为7.01 mol NH _3。/ mol IL，大约是传统IL的30倍。双官能化PIL的优异的NH ₃吸收性能归因于质子与NH ₃分子之间的氢键相互作用，以及基于Li ⁺的阴离子与NH ₃分子之间形成配位络合物。另外，在此研究的离子液体表现出优异的再利用性，这表明它们在涉及高效和可逆NH应用中使用的潜力很大₃选自NH吸收₃含工业气体。