Straightforward Loading of Imidazole Molecules into Metal–Organic Framework for High Proton Conduction

A one-step straightforward strategy has been developed to incorporate free imidazole molecules into a highly stable metal–organic framework (<b>NENU-3</b>, ([Cu₁₂(BTC)₈(H₂O)₁₂]­[HPW₁₂O₄₀])·Guest). The resulting material <b>Im@(NENU-3)</b> exhibits a very high proton conductivity of 1.82 × 10^–2 S cm^–1 at 90% RH and 70 °C, which is significantly higher than 3.16 × 10^–4 S cm^–1 for <b>Im-Cu@(NENU-3a)</b> synthesized through a two-step approach with mainly terminal bound imidazole molecules inside pores. Single crystal structure reveals that imidazole molecules in <b>Im-Cu@(NENU-3a)</b> isolate lattice water molecules and then block proton transport pathway, whereas high concentration of free imidazole molecules within <b>Im@(NENU-3)</b> significantly facilitate successive proton-hopping pathways through formation of hydrogen bonded networks

Additional file 1: Table S1. of CMISG1701: a multicenter prospective randomized phase III clinical trial comparing neoadjuvant chemoradiotherapy to neoadjuvant chemotherapy followed by minimally invasive esophagectomy in patients with locally advanced resectable esophageal squamous cell carcinoma (cT3-4aN0-1M0) (NCT03001596)

Treatment schedule. (DOCX 20 kb