Study on the synthesis process of BDC materials based on different metal centers and their ammonia adsorption performance

With the implementation of China’s ‘dual – carbon’ strategy, hydrogen energy has emerged as the key to the development of new energy, given its green and low – carbon nature as well as abundant sources. High – efficiency ammonia storage technology plays a crucial role in the hydrogen energy industry. Due to their large specific surface area, designability, and diversity, metal – organic frameworks (MOFs) hold great potential for the adsorption and storage of ammonia (NH₃). In this study, Al3 +, Fe3 +, Co2 +, and Ni2 + metal ions, along with the organic carboxylic acid ligand terephthalic acid (H₂BDC), were used to synthesize flexible metal – organic framework materials MIL − 53 (Al3 +, Fe3 +) and transition – metal framework materials M – BDC (M = Co2 +, Ni2 +) through the solvothermal method. Their structural properties and NH₃ adsorption characteristics were systematically analyzed. Discovery Al-BDC exhibited the highest NH₃ adsorption capacity of 80.36 mg·g− 1, followed by Fe-BDC (57.17 mg·g− 1), Co-BDC (38.01 mg·g− 1), and Ni-BDC (19.89 mg·g− 1), demonstrating that metal center Lewis acidity and pore structure significantly influence adsorption performance. This research provides a theoretical basis for the development of solid ammonia storage technology with high safety and large storage capacity and is expected to promote the industrial application of flexible MOFs materials in the field of solid ammonia storage.