| Vo lat ile organic compound s（VOC s）are important at mospheric polluta nts,whic h are easy to react w it h other nitroge n oxides to for m photochemica l s mog,w hich are ver y har mful to human hea lth.There fore,the detection and governa nce of VO Cs is imminent.N owadays,there are many kinds of detect ion methods,however,some proble ms still rema in,such as the difficulty in miniat ur izat io n of instr ument a nd in portability,t ime-consuming process,high cost and so on.The fluorescence sensing met hod combined with fluorescent probe not only has high sens it ivit y,good s electivit y,short response time and low detection limit,but also can realize remote and real-time monitor ing,w hich has great develop ment prospects due to its obvious advanta ges.There fore,like other se nsors,t he key to t he exce llent performa nce of fluorescent sensors lies in the creation of low-cost fluorescent sensing mater ia ls and devices wit h exce llent fluorescence response properties.Based on this purpose,the mo lecular des ign and properties of t he non-toxic and environme nt-fr iend ly cuprous comple xes for VO C s fluorescence sensing mater ia ls were studied in t his paper,and the fluorescence response detection performa nce of cuprous comple xes under differe nt VO C s atmospheres was explored.Specifica lly,a series o f cuprous comp lexes were obtained by designing the mo lecular str ucture o f t he sens ing response,and the ir s ingle crystal str ucture and fluorescence properties were studied in detail,and the relat ions hip between the structure and properties of the materia ls was deeply discussed.Then,for t he mater ia ls w ith fluorescence sensing properties,the fluorescence detection of VO C s response based on differe nt supporters and different concentrat ions was tested.The selectivity,sens it ivity and the ir princ ip les of VO C s response were studied in detail.The details are listed below:1)Design,s ynt hes is,struct ure and properties of cuprous co mple xes based on VO Cs fluorescence sensing.Respective ly,us ing[C u PN 2],[C u P2N2]and C u I as the center,o-tol3p,2-（2-pyridyl）benzoxa zole（2-PBO）and trip henylphosphine（PPh3）as the first ligand,phena nt hroline（phe n）,4,5-diazafluorene（DAFR）,2-（2-pyridyl）benzoxa zole,PPh3,bis（2-diphenyl-phosphine）ether（PO P）,4,5-bis（diphe nylp hosphine）-9,9-dimet hylo xant hene（hereina fter referred to as xanthe ne,Xa ntphos）,1,1’-bis（diphenylp hosphine）ferrocene（DPPF）,2-mercaptobenzimidazo le（MBI）and thiourea（TU）as the second ligand,a total of 10 cuprous comple xes were designed and synthes ized.Amo ng t he m,four k inds o f three-coordinated ionic c uprous comp lexes 1-4（comple x 1:[C u（o-tol3p）（phen）]PF 6;comple x 2:[C u（o-tol3p）（DAFR）]PF6;comple x 3:[C u（o-tol3p）（2-PBO）]PF6;comple x 4:[C u（o-tol3p）（2-PBO）]PF6（C H2C l2））with[C u PN2]as the center were synthes ized;taking[C u P2N2]as the center,successfully synt hes ized four tetra-coordinated io nic copper comple xes 5-8（complex 5:[C u（2-PBO）（PPh3）2]PF6;complex 6:[C u（2-PBO）（POP）]PF 6;complex 7:[C u（2-PBO）（xantphos）]PF6;comple x 8:[C u（2-PBO）（DPPF）]PF6）;two neutral cuprous comple xes 9-10（complex 9:C u I（PPh3）2（MBI）;comp lex 10:C u I（PPh3）2（TU））were designed and synt hes ized with C u I as the centra l me ta l.It was found that t he luminescent e ffic iency of tetra-coordinated[C u（P 2）N2]+comple x was significant ly higher than that of tri-coordinat ion.Thiose micarbazide and copper halide for med S-C u bond,but the luminescent e ffic ie ncy was not high.Based on the mecha nis m t hat the geometr ic changes fro m tr iangle coordinat ion to tetrahedral coordinat ion leads to the change of luminescent effic ie ncy,tri-coordinated cuprous comple xes have the potentia l to combine VO C s gas coordinatio n and generate fluorescence response signal.2)Study on the detection of VO C s by fluorescence sensing response of mo lecular cuprous comp le xes.Firstly,the pure phase mater ia l 11-13(comple x 11:[C u（PPh3）2（C H3CN）2]PF6;complex 12:[C u（PPh3）2（phen）]PF6;comple x 13:[C u I（PPh3）2]（C H3CN）were prepared.Then,for the VO C s response of the ionic copper complex 11,when PMMA on quartz plate was used as the substrate,the 50%concentration film s howed better selectivity and sensit ivity;after exposed to pyridine,3-cyanopyrid ine,4-methylp yr id ine and other atmospheres,the naked eye could see that the luminescence changed significa nt ly and t he luminescence color was d ifferent,w hich had the fluorescent light ing effect;t he fluorescent light was cont inuo us ly detected in pyr id ine and other atmospheres;it is fo und that t he fluorescence changes can be detected in t he instr ument after 10 minutes,w hich ind icates that the response of mater ia l 11 to VOC s is not only se lective but a lso sensit ive.The n,the VOC s response of ionic mater ia l 12 was studied.The filter paper was used as supporter.After the test paper was exposed to vapor such as 3-cyanopyrid ine,forma ldehyde and acetone for 30 min,the vis ible light emiss io n under UV la mp cha nged significant ly,whic h indicated that the VO C s oriented sensing film could be prepared by using filter paper as supporter.In order to further improve t he VO C s fluorescence sens ing performa nce,the VO C s response of haloge n-containing mater ia l 13 was tested.When quartz p late was used as the supporter and PMMA as the substrate,the selectivit y and sensit ivit y of the film w ith 50%concentration showed excellent select ivit y and sens it ivit y;a fter exposure to acetone,pyrid ine and 3-aldehyde pyr idine,the light e miss ion o f t he eye changed significa nt ly and the luminescence color was different.In t he atmosphere of4-methylpyr id ine,acetone and p yrid ine,cont inuous detectio n of fluorescence spectra showed that the fastest response was less 2 minutes,and the fluorescence could be detected obvious ly by the instrume nt.At the sa me time,the sens it ive cha nge o f fluorescence can be observed by naked e yes under ultravio let la mp after exposed to toluene,xyle ne,ethyl acetate,pyridine,3-cyanopyr idine,benze ne and methyla mine.A ll t hese ind icate that the mater ia l 13 has good selectivity and sens it ivit y to VOC s.Further optimizat ion and practical develop ment work on these materia ls are in progress. |
