Abstract
A novel covalent, metal-free, photocatalytic material is prepared by thermal polymerization of barbituric acid (BA). The structure of the photocatalyst is analyzed by using scanning electron microscopy, X-ray diffraction, and infrared, UV-visible, and 1 H solution and 13 C solid-state NMR spectroscopy. The photodegradation efficiency of BA thermally polymerized at different temperatures is tested by photocatalytic degradation of aquatic rhodamine B (RhB) dye under visible-light irradiation. It is shown that heating BA at an optimized temperature of 300 °C, that is, still in the range that polymer-like polycondensation takes place, results in a photocatalyst that can remove RhB with 96% photodegradation efficiency after 70 min exposure to visible light. The polycondensation reaction of BA is identified to process through precipitation of trimer units as primary building blocks. Reference experiments such as addition of scavengers and saturation with oxygen are studied to understand the photodegradation process. It is shown that the presence of triethanolamine, and excess of oxygen and p-benzoquinone in the solution of RhB and photocatalyst (BA300) is not beneficial, but decreases the photodegradation efficiency.
Highlights
A novel covalent, metal-free, photocatalytic material is prepared by thermal amount of research on the use of BA in supramolecular chemistry, there is a little polymerization of barbituric acid (BA)
Barbituric acid (BA) is a simple and omnipresent organic mole lyzed by thermogravimetric analysis (TGA), CHNO elemental cule, which just recently is employed as a comonomer for analysis, scanning electron microscopy (SEM), N2 adsorption– designing new carbon nitride materials.[1]
Using SEM, we find that the microstructure at 300 °C (BA300, Figure 1b), resembles a morphology close to BA powder (Figure 1a inset) but with distinct cavities in an otherwise mostly prevailed structure, that is, the mass loss is mostly related to a condensation of the monomer, either in a topotactic fashion or by a melting–reprecipitation process[9] The particles flatten and thin out by heating to 350 °C (BA350, Figure 1c), while a porous, irregular structure evolves as BA is further heated up to 450 °C (BA450, Figure 1d) and 550 °C (BA550, Figure 1e)
Summary
A novel covalent, metal-free, photocatalytic material is prepared by thermal amount of research on the use of BA in supramolecular chemistry, there is a little polymerization of barbituric acid (BA). Peaks at 13.6° and 27.8° are related to (100) and (002) crystallographic planes indicating presence of aromatic stacking of conjugated systems (002) and in-planar repetition of aromatic units (100) similar to those observed in graphitic carbon nitride materials and in other conducting polymers.[12,13] The peak at 27.8° becomes broader and shifts to lower angles at higher temperatures, proving that secondary lateral condensation induces disorder in local packing.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
