240 elemental analyzer

Organic ligands 5-(3-(pyridin-3-yl)benzamido)isophthalic acid (3-H₂PBI) and 5-(3-(pyridin-4-yl)benzamido)isophthalic acid (4-H₂PBI) were synthesized according to reported methods.^{26,27 (link)} Infrared spectra were collected with KBr pellets on a Nicolet/Nexus-670 FT-IR spectrometer. Elemental analyses were obtained by a PerkinElmer 240 elemental analyzer. Thermogravimetric analyses (TGA) were conducted on a Netzsch Thermo Microbalance TG 209 F1 Libra from room temperature to 900 °C with a heating rate of 10 °C min⁻¹ under N₂ atmosphere. Powder X-ray diffraction patterns (PXRD) were recorded on a Bruker D8 Advance diffractometer with a Cu target tube and a graphite monochromator.

For the experimental work, the chemicals were purchased by aura, spectrochem & TCI and without further purification. In the laboratory, thin layer chromatography (TLC) took by 0.25-mm e merck gel Plates (60F-254). Synthesized compounds were dissolved in a minimum amount of acetic acid, spotted on the given TLC plate, and ran through a solution of ethyl acetate and benzene. The melting point determination of compounds was done by digital apparatus koefler banc. The elemental analysis of the synthesized compounds was carried out through perkin-elmer 240 elemental analyzer. The structure of unknown compounds was agreed upon by different spectral characterization. FT-IR spectrometer was recorded KBr pellets on a perkin-elmer 2000 at 8 cm⁻¹ resolution in the region 4000-400 cm⁻¹. ¹H NMR spectra were carried out with bruker avance III HD 300/400 operating at 300/400 MHz using CDCl₃ solution with TMS at internal standard. ¹³C NMR spectra obtained with bruker avance III HD 300 operating at 300 MHz using CDCl₃ solution with TMS at internal standard. Mass spectra recorded on LC-MS (ESI) mass spectrometer at 70 ev.

All chemicals were obtained from Aladdin (Shanghai) or Chengdu Kelong Chemical Co., Ltd. (Chengdu). H₂L2 and H₂L3 were synthesized according to the previous method.^{15 (link)} NMR spectra were recorded on a Bruker advance II 400 MHz NMR spectrometer. All FT-IR absorption spectroscopy were obtained from a Nicolet 6700 with KBr pellets. X-ray powder diffractions were collected by Rigaku Dmax/Ultima IV diffractometer. Thermogravimetric analyses (TGA) were obtained from a Netzsch STA 449 F3 thermal analyzer. Elemental analyses were acquired from a PerkinElmer 240 elemental analyzer. Nitrogen adsorption isotherms were recorded at 77 K via Autosorb-IQ gas analyzer. Brunauer–Emmett–Teller (BET) method was employed for evaluating the specific surface area and pore size distribution. Fluorescence measurements were conducted on a Cary Eclipse fluorescence spectrophotometer. Electrochemical activities of 1–4 for OER were examined using a CHI-660E electrochemical workstation equipped with a standard three electrode system.

PerkinElmer 240 elemental analyzer was used for elemental analysis. Infrared spectra (400–4000 cm⁻¹) were recorded using KBr pellets on a Nicolet Magna IR 750 series-II FTIR spectrophotometer. A Bruker 300 MHz NMR spectrometer was used for ¹H-NMR recorded in the DMSO-d₆ solvent and using tetramethylsilane (δ = 0) as an internal standard. An Agilent diode-array spectrophotometer (model, Agilent 8453) was used for recording UV-Vis spectra, a Hitachi-7000 spectrofluorimeter was used for recording steady-state fluorescence, ESI-MS⁺ (m/z) of the ligand and Al(iii)-complex were recorded on a Waters' HRMS spectrometer (model: XEVOG2 QTOF). To analyse the morphology of DFP–AMQ in the solid state, FESEM images were taken using an EVO LS10 scanning electron microscope (SEM). For the pH study, a systronics digital pH meter (model 335) was used and 50 mM HCl or NaOH solution was used for the adjustment of pH. The particle size distribution was measured by dynamic light scattering (DLS) on a Malvern Zetasizer Nano ZS90 instrument. Optical fluorescence microscopy images were taken using a LEICA DM1000 LED upright microscope.