2026-10-13T01:42:20Z https://api.figshare.com/v2/oai

oai:figshare.com:article/34023783 2026-09-29T12:41:48Z category_1 category_4 category_146 category_12 category_873 category_39 category_45 category_69 portal_63 item_type_6 month_year_09_2026

Enhancing the Adsorption Sites of NH₂‑MIL-125 via a Copper Modification Strategy for Improved CO₂ Capture and CO₂/N₂ Separation Weihang Han (20078790) Xiaojing Liu (1282134) Ruoshi Luo (11849225) Lin Hu (562273) Jianjian Wang (288375) Ziyi Wang (1956610) Feng Huo (1435492) Dan Wang (34472) Biophysics Biochemistry Space Science Cell Biology Chemical Sciences not elsewhere classified Ecology Sociology Inorganic Chemistry theoretical calculations reveal specific surface area copper modification strategy 36 mmol g 20 consecutive cycles 01 mmol g precursor significantly compromised copper precursor selection copper precursor plays neighboring amino groups 2 +</ sup synthesized using cucl coo )< sub 3 </ sub 2 </ sub accessible adsorption sites 4 </ sub adsorption sites adsorption capacity promising adsorbent pore environment new material material ’ great significance findings highlight electronic environment decisive role critical role coordination modifies collectively enhance 273 k 1 bar Developing efficient adsorbents for CO₂ capture and CO₂/N₂ separation is of great significance for mitigating greenhouse gas emissions. In this study, NH₂-MIL-125 was modified with Cu²⁺ using different copper precursors, including Cu(NO₃)₂, CuSO₄, Cu(CH₃COO)₂, and CuCl₂, to regulate the adsorption sites and improve the CO₂ affinity of the framework. When synthesized using CuCl₂ as the precursor, CuC-NH₂-MIL-125 exhibited an enhanced CO₂ adsorption capacity of 6.36 mmol g^–1 at 273 K and 1 bar, representing a 58% improvement over pristine NH₂-MIL-125 (4.01 mmol g^–1). The CO₂/N₂ selectivity for this new material is 22.4 at 273 K, and it could also maintain stable adsorption performance over 20 consecutive cycles. In contrast, the use of Cu(NO₃)₂ and CuSO₄ as the precursor significantly compromised the capture capacity of CO₂, indicating that the copper precursor plays a critical role in determining the pore environment and accessible adsorption sites. Further analysis using different contents of CuCl₂ was conducted, and theoretical calculations reveal that the Cu ion is anchored to the −NH₂ groups while preserving the microporous framework and the specific surface area of CuC-NH₂-MIL-125 was further increased. The Cu²⁺ coordination modifies the electronic environment of neighboring amino groups, which collectively enhance the material’s affinity for CO₂. These findings highlight the decisive role of copper precursor selection in governing the CO₂ capture performance of Cu-modified NH₂-MIL-125 and identify CuCl₂ derived CuC-NH₂-MIL-125 as a promising adsorbent for practical CO₂/N₂ separation. 2026-09-29T00:00:00Z Text Journal contribution 10.1021/acs.langmuir.6c03959.s001 https://figshare.com/articles/journal_contribution/Enhancing_the_Adsorption_Sites_of_NH_sub_2_sub_MIL-125_via_a_Copper_Modification_Strategy_for_Improved_CO_sub_2_sub_Capture_and_CO_sub_2_sub_N_sub_2_sub_Separation/34023783 CC BY-NC 4.0