Synthesis of a Ce-Based MOF-76 with High Yield: A Study of Reaction Parameters Based on a Factorial Design

Abstract

The purpose of this work was to optimize the synthesis yield of {[Ce(BTC)(H 2 O)]•DMF} n , a metal-organic framework (MOF)-76 family member, by solvothermal method. CeCl 3 .7H 2 O and 1,3,5-benzenetricarboxylic acid, 2:1 molar proportion, were added to N,N-dimethylformamide (DMF). Reaction time and temperature were evaluated to optimize the synthesis through a factorial design followed by a statistical analysis of the response variable (reaction yield). Infrared spectroscopy (IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analyses were performed to characterize the obtained white powders. Reaction yield was estimated based on {[Ce(BTC)(H 2 O)]•DMF} n molecular formula, which was confirmed by analytical techniques. The proposed statistic model of the response variable showed good agreement with the experimental values. Temperature parameter was the only significant variable on the reaction yields, being the highest yield (94.4%) obtained at 115 °C for 36 h, and it was accompanied by an improvement on the particle morphology (uniformity of shape and size), forming particles with strawsheave-like morphology.

A facile synthesis of CeO2 from the GO@Ce-MOF precursor and its efficient performance in the oxygen evolution reaction

“…This could be the possible explanation for the prospect of GO@ Ce-MOF crystals being evenly distributed throughout the spaces between GO sheets. The characteristic peaks of Ce-MOF and its MOF-76 family may be seen in a diffractogram of GO@Ce-MOF at 8.4 and 10.6 ° (Almáši et al, 2015;Almáši et al, 2016;Zhang et al, 2017b;Zhang et al, 2018;Santos and Luz, 2020), proving that GO in place has no effect on the synthesis of Ce-MOF. The synthesized Ce-MOF shows highly ordered Ce-MOF units inside the respective composite, and the diffraction peaks of Go@Ce-MOF indicate that GO's presence obstructing neither the crystallization of the Ce-MOF edifice nor that of the composites having a Ce-MOF structure in it.…”

Production of an Efficient Magnetic Adsorbent From Babassu Coconut Endocarp and Ni Particles for Easy Dye Removal From Mimetic Contaminated Effluents

“…The p-value describes the probability of result signi cance, in which values smaller than 0.05% indicate that a certain factor exerted in uence on the response variable. From the interpretation of the statistical model, only the interaction between factors in uences considerably the response variable value (p-value = 0.000009); therefore, the combination between Ni concentration and adsorption time presents greater signi cance in the result (Amorim et al 2018;Santos and Luz 2020).…”

Síntese e caracterização de Ce-MOFs como catalisadores heterogêneos na redução de CO>sub<2>/sub<

“…A fim de identificar os grupos funcionais nos materiais obtidos, foi feita a espectroscopia na região do infravermelho. Na Figura 13 observa-se uma banda intensa em 3473 𝑐𝑚 −1 atribuída ao estiramento da ligação O-H da molécula de água coordenada na estrutura da MOF, provavelmente procedente do precursor Ce(NO3)3•6H2O ou absorvidas do ambiente, e a qual é ausente no ácido tereftálico (Almási et al, 2014, Santos et al, 2020. Na Figura 14, observa-se de novo a banda intensa em torno de 3400𝑐𝑚 −1 associada à molécula de água ligada na estrutura da MOF, os estiramentos assimétricos e simétricos em 1587 e 1395𝑐𝑚 −1 do grupo 𝐶𝑂𝑂 − .…”