C≡N缺陷C3N5催化剂的制备及其光催化活化过硫酸盐降解亚甲基蓝性能  

Preparation of C≡N defect C 3N 5 catalyst and its photocatalytic activity for degradation of methylene blue by persulfate activation

作　　者：王淑敏[1] WANG Shumin(Hebi Polytechnic,Hebi,Henan 458030,China)

机构地区：[1]鹤壁职业技术学院,河南鹤壁458030

出　　处：《毛纺科技》2025年第4期24-32,共9页Wool Textile Journal

基　　金：河南省高等学校重点科研项目(21B150010)。

摘　　要：采用硫脲和3-氨基-1,2,4-三唑混合原位热聚合制备C≡N缺陷C_(3)N_(5)(C_(3)N_(5)—C≡N)光催化剂,通过X射线衍射(XRD)、傅里叶红外光谱(FTIR)、扫描电镜(SEM)、X射线光电子能谱(XPS)、电子顺磁共振波谱(EPR)、紫外可见漫反射光谱(UV-vis DRS)和稳态荧光光谱(PL)等表征手段对C_(3)N_(5)—C≡N光催化剂的物相晶型、特征基团、微观形貌、元素组成、缺陷构建、光谱吸收响应和光电子-空穴重组等进行了详细分析。结果表明:波数2176 cm^(-1)位置吸收峰和286.5 eV位置拟合峰的出现证明了C≡N缺陷的成功构建,Lorentz信号强度的增强说明缺陷的构建促进了未配对电子的生成,发射峰的降低说明了光电子-空穴的重组得到了有效抑制,吸收边界的红移说明了光谱响应范围得到拓宽,有利于光催化性能的提升。太阳光照射下,C_(3)N_(5)—C≡N光催化剂协同过硫酸盐(PMS)表现出优异的光催化活性,对亚甲基蓝(MB)染料溶液的降解率达到了99.10%,循环使用5次后MB染料溶液的降解率为97.80%,表现出良好的化学稳定性。活性基团捕获说明超氧自由基(·O_(2)^(-))、空穴(h^(+))、单线态氧(^(1)O_(2))、羟基自由基(·OH)和硫酸根自由基(·SO_(4)^(-))均参与了反应,·O_(2)^(-)和^(1)O_(2)起主要作用。C≡N-deficient C_(3)N_(5)(C_(3)N_(5)—C≡N)photocatalysts were prepared by in situ thermal polymerization of thiourea and 3-amino-1,2,4-triazole.X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),electron paramagnetic resonance spectroscopy(EPR),UV-vis diffuse reflectance spectroscopy(UV-vis DRS)and steady-state fluorescence spectroscopy(PL)were used to characterize the phase crystal form,characteristic groups,microstructure,elemental composition,defect construction,spectral absorption response and photoelectron-hole recombination of C_(3)N_(5)—C≡N photocatalyst.The results show that the absorption peak at 2176 cm-1 and the fitting peak at 286.5 eV prove the successful construction of C≡N defects.The enhancement of Lorentz signal intensity indicates that the construction of defects promotes the generation of unpaired electrons.The decrease of emission peak indicates that the recombination of photoelectron-holes is effectively suppressed.The red shift of absorption boundary indicates that the spectral response range is broadened,which is beneficial to the improvement of photocatalytic performance.Under sunlight irradiation,C_(3)N_(5)—C≡N photocatalyst synergistic persulfate(PMS)showed excellent photocatalytic activity,and the degradation rate of methylene blue(MB)dye solution reached 99.10%.The degradation rate of MB dye solution was 97.80%after 5 cycles,showing good chemical stability.The capture of active groups indicated that superoxide radicals(·O_(2)^(-)),holes(h^(+)),singlet oxygen(^(1)O_(2)),hydroxyl radicals(·OH)and sulfate radicals(·SO_(4)^(-))were involved in the reaction,and·O_(2)^(-)and ^(1)O_(2) played a major role.

关 键 词：C≡N缺陷 富氮氮化碳 光催化 过硫酸盐 亚甲基蓝 

分 类 号：O648.17[理学—物理化学] TS193.2[理学—化学]