10.1016/j.matdes.2016.08.043
Thermally induced formation of zinc oxide nanostructures with tailoring morphology during metal organic framework (MOF-5) carbonization process
Hydrochloric acid (36%) and N,N-dimethylformamide were purchased from Chempur (Poland). Zinc nitrate hexahydrate (Zn(NO3)2*6H2O), terephthalic acid (C6H4 (COOH)2) and triethylamine were bought from Sigma Aldrich. 
The MOF-5 was prepared according to a previously reported procedure [26]. Briefly, 1.65 mmol of zinc nitrate hexahydrate, 0.89 mmol terephthalic acid and 3.25 mmol triethylamine (TEA) were dissolved in 2.34 mol N,N-dimethylformamide (DMF). The mixture was sonicated for 1 h. The solution obtained was transferred into an autoclave and stirred for 48 h at a temperature of 150 degC. The reaction vessel was then removed from the autoclave and allowed to cool to room temperature. Finally, the sample was vacuum-dried at 110 degC for about 2 h to remove the solvent. 
Porous carbon was prepared by direct thermolysis of the previously obtained MOF-5. A ceramic boat containing the white MOF-5 powder was inserted into the centre of a tube furnace. The furnace was then heated from room temperature to the desired temperature (between 600 degC to 1000 degC), with a heating rate of 8 degC/min, The MOF-5 powder was maintained at this temperature for 2 h with an Ar flow of 100 ml/min. Cooling the MOF-5 back down to room temperature was followed by an investigation of the morphology of the samples obtained.
Hydrochloric acid
36%
%
zinc nitrate hexahydrate
dissolved
1.65 mmol
mmol
terephthalic acid
dissolved
0.89 mmol
mmol
triethylamine (TEA)
dissolved
3.25 mmol
mmol
N,N-dimethylformamide (DMF)
2.34 mol
mol
mixture
sonicated
1 h
h
solution
stirred
48 h
h
solution
temperature
150 degC
degC
sample
vacuum-dried
110 degC
degC
sample
vacuum-dried
2 h
h
furnace
heated
between 600 degC to 1000 degC
degC
MOF-5 powder
maintained at this temperature
2 h
h
furnace
heating rate
8 degC/min
degC/min
MOF-5 powder
Ar flow
100 ml/min
ml/min