The coating material is considered as the key of solid-phase microextraction(SPME)due to the fact that which has much effect on the selectivity and sensitivity of the analytical method.Herein,the porous hollow carbon ...The coating material is considered as the key of solid-phase microextraction(SPME)due to the fact that which has much effect on the selectivity and sensitivity of the analytical method.Herein,the porous hollow carbon nanospheres(PHCNs)were synthesized by selectively removing the interior part of solid inhomogeneous nanospheres with acetone.Using PHCNs as new coating material,a SPME fiber was prepared.To the best of our knowledge,PHCNs was utilized as a SPME fiber coating for the first time.The fiber coating material PHCNs demonstrated excellent thermal stability(>800℃)and long usage lifespan(≥60 times).A headspace SPME(HS-SPME)was established to non-contact extract and enrich polycyclic aromatic hydrocarbons(PAHs)prior to gas chromatography-flame ionization detector(GC-FID)analysis.The HS-SPME not only can eliminate non-volatile interferences from matrix,but also be able to protect fiber coating and prolong lifespan of fiber prober.The linearity in the linear range of 0.01-30 ng/m L and limits of detection from 0.003 ng/mL to 0.006 ng/mL were obtained by HS-SPME-GC-FID with PHCNs as fiber coating.The enrichment factors were calculated as 5420-9211 compared with conventional direct introduce analysis.The spiked recoveries of real samples including campus lake water and lime tree honey were obtained from 80.93%to 118.0%with relative standard deviation no higher than 10.6%.The π-π stacking interaction,CH/π interaction,and unique built-in cavities significantly enhance the extraction performance of PHCNs coating fiber to PAHs.This work demonstrated that the PHCNs as fiber coating materials present good application prospects for the extraction and enrichment of trace PAHs from complex matrixes.展开更多
Aromatic carbon nitride(PhCN),as an emerging semiconductor material,has attracted much attention due to its excellent optical properties.Fully understanding the synthesis mechanism,chemical structure,and optical prope...Aromatic carbon nitride(PhCN),as an emerging semiconductor material,has attracted much attention due to its excellent optical properties.Fully understanding the synthesis mechanism,chemical structure,and optical properties of PhCN would significantly promote its progress in synthesis,modifications and applications.Here the chemical structures and optical properties of PhCN and intermediates have been systematically studied,and hereby the synthesis mechanism of PhCN is explicitly proposed for the first time.The results show that the precursor 2,4-diamino-6-phenyl-1,3,5-triazine(DPT)is deaminated to form the DPT dimer,trimer and polymers,and then the triazine was isomerized to tri-s-triazine by a ringopening isomerization reaction to form PhCN.Meanwhile,the correlation between structural and optical properties of PhCN and intermediates demonstrates the electron delocalization effect of the phenyl group and reveals that highly polymerized PhCN has a more stable molecular structure,thus exhibiting more stable photophysical properties.Our work provides a fundamental study from synthesis to structures and optical properties of PhCN,which will certainly promote its deeper research and wider application.展开更多
基金supported by National Natural Science Foundation of China(No.22376053)supported by the Natural Science Foundation of Henan Province,China(No.242300421034)Henan Key Scientific Research Programs to Universities and Colleges(No.22ZX003)。
文摘The coating material is considered as the key of solid-phase microextraction(SPME)due to the fact that which has much effect on the selectivity and sensitivity of the analytical method.Herein,the porous hollow carbon nanospheres(PHCNs)were synthesized by selectively removing the interior part of solid inhomogeneous nanospheres with acetone.Using PHCNs as new coating material,a SPME fiber was prepared.To the best of our knowledge,PHCNs was utilized as a SPME fiber coating for the first time.The fiber coating material PHCNs demonstrated excellent thermal stability(>800℃)and long usage lifespan(≥60 times).A headspace SPME(HS-SPME)was established to non-contact extract and enrich polycyclic aromatic hydrocarbons(PAHs)prior to gas chromatography-flame ionization detector(GC-FID)analysis.The HS-SPME not only can eliminate non-volatile interferences from matrix,but also be able to protect fiber coating and prolong lifespan of fiber prober.The linearity in the linear range of 0.01-30 ng/m L and limits of detection from 0.003 ng/mL to 0.006 ng/mL were obtained by HS-SPME-GC-FID with PHCNs as fiber coating.The enrichment factors were calculated as 5420-9211 compared with conventional direct introduce analysis.The spiked recoveries of real samples including campus lake water and lime tree honey were obtained from 80.93%to 118.0%with relative standard deviation no higher than 10.6%.The π-π stacking interaction,CH/π interaction,and unique built-in cavities significantly enhance the extraction performance of PHCNs coating fiber to PAHs.This work demonstrated that the PHCNs as fiber coating materials present good application prospects for the extraction and enrichment of trace PAHs from complex matrixes.
基金supported by the Taishan Scholar Program,Natural Science Foundation of Qingdao,China(23-2-1-245-zyyd-jch)National Natural Science Foundation of China(52171140).
文摘Aromatic carbon nitride(PhCN),as an emerging semiconductor material,has attracted much attention due to its excellent optical properties.Fully understanding the synthesis mechanism,chemical structure,and optical properties of PhCN would significantly promote its progress in synthesis,modifications and applications.Here the chemical structures and optical properties of PhCN and intermediates have been systematically studied,and hereby the synthesis mechanism of PhCN is explicitly proposed for the first time.The results show that the precursor 2,4-diamino-6-phenyl-1,3,5-triazine(DPT)is deaminated to form the DPT dimer,trimer and polymers,and then the triazine was isomerized to tri-s-triazine by a ringopening isomerization reaction to form PhCN.Meanwhile,the correlation between structural and optical properties of PhCN and intermediates demonstrates the electron delocalization effect of the phenyl group and reveals that highly polymerized PhCN has a more stable molecular structure,thus exhibiting more stable photophysical properties.Our work provides a fundamental study from synthesis to structures and optical properties of PhCN,which will certainly promote its deeper research and wider application.
