The design and fabrication of TiO_(2)/Bi_(4)O_(5)Br_(2)step-scheme heterojunctions for the photodegradation of gaseous hydrogen sulfide:DFT calculation,kinetics,pathways,and mechanisms  

用于光降解气态硫化氢的TiO_(2)/Bi_(4)O_(5)Br_(2)阶梯型异质结的设计和制备:DFT计算、动力学、路径和机制

作　　者：Baofei Hao Younes Ahmadi Jan Szulejko Tianhao Zhang Zhansheng Lu Ki-Hyun Kim 郝宝飞;Younes Ahmadi;Jan Szulejkoa;张天豪;路战胜;Ki-Hyun Kima(汉阳大学土木与环境工程系,首尔,韩国;北京化工大学数理学院,北京100029;河南师范大学物理学院,先进半导体与功能器件集成河南省重点实验室,河南新乡453007)

机构地区：[1]Department of Civil and Environmental Engineering,Hanyang University,222 Wangsimni-ro,Seoul 04763,Republic of Korea [2]School of Mathematics and Physics,Beijing University of Chemical Technology,Beijing 100029,China [3]Henan Key Laboratory of Advanced Semiconductor&Functional Device Integration,School of Physics,Henan Normal University,Xinxiang 453007,Henan,China

出　　处：《Chinese Journal of Catalysis》2025年第1期282-299,共18页催化学报(英文)

基　　金：国家自然科学基金(12274118);河南省杰出外籍专家工作室(GZS2023007);河南省高等学校重点科研项目计划基础研究专项(22ZX013).

摘　　要：It is a challenging task to efficiently convert deleterious hydrogen sulfide(H_(2)S)into less harmful products such as SO_(4)^(2-)species.In an effort to address such issue,a step-scheme(S-scheme)heterojunction photocatalyst has been built by concatenating TiO_(2)(P25)and ultrathin Bi_(4)O_(5)Br_(2)into TiO_(2)/Bi_(4)O_(5)Br_(2)(namely,x-TB-y:x and y denote the molar ratio of TiO_(2):Bi_(4)O_(5)Br_(2)and pH value for solution-based synthesis,respectively)via in-situ hydrothermal method.The S-scheme charge transfer pathway in TB is confirmed by electron spin resonance and band structure analysis while experimental data and density functional theory calculations suggest the formation of an internal electric field to facilitate the separation and transfer of photoinduced charge carriers.Accordingly,the optimized heterojunction photocatalyst,i.e.,5-TB-9,showcases significantly high(>99%)removal efficiency against 10 ppm H_(2)S in a 17 L chamber within 12 minutes(removal kinetic rate r:0.7 mmol·h^(-1)·g^(-1),specific clean air delivery rate SCADR:5554 L·h^(-1)·g^(-1),quantum yield QY:3.24 E-3 molecules·photon^(-1),and space-time yield STY:3.24 E-3 molecules·photon^(-1)·mg^(-1)).Combined analysis of in-situ diffuse reflectance infrared Fourier transform adsorption spectra and gas chromatography-mass spectrometry allows to evaluate the mechanisms leading to the complete degradation of H_(2)S(i.e.,into SO_(4)^(2-)without forming any intermediate species).This work demonstrates the promising remediation potential of an S-scheme TiO_(2)/Bi_(4)O_(5)Br_(2)photocatalyst against hazardous H_(2)S gas for sustainable environmental remediation.大气污染已成为威胁人类健康和破坏生态系统的重大问题.其中,硫化氢(H_(2)S)因其强烈的毒性、腐蚀性和刺鼻的气味而函需得到有效解决.尽管生物降解、化学吸附和物理吸附等传统方法已被用于去除H_(2)S,但其降解效果仍不理想.光催化降解H_(2)S因其环境友好和可持续发展的优点而受到越来越多的关注.然而,电子-空穴对(e-h)的重组现象严重抑制了光催化降解H_(2)S的效率.为了解决上述问题,本文通过原位水热法将TiO_(2)(P25)和Bi4O,Br2薄片组合成TiO_(2)/Bi_(4)O_(5)Br_(2)异质结光催化剂(命名为x-TB-y:其中x和y分别表示TiO_(2):Bi_(4)O_(5)Br_(2)摩尔比和合成溶液的pH值),并构建了阶梯结构(S-scheme).通过X射线粉末衍射和傅里叶变换红外光谱(FT-IR)证明了TiO_(2)/Bi_(4)O_(5)Br_(2)复合材料的成功制备。扫描电镜和透射电镜结果表明,在TiO_(2)/Bi_(4)O_(5)Br_(2)复合材料中,TiO_(2)和Bi_(4)O_(5)Br_(2)分别呈现为球状和片装形貌.利用X射线电子能谱(XPS)技术,并结合密度泛函理论计算揭示了该材料的内部电场结构.光电流强度曲线和电化学阻抗曲线表明,相较于TiO_(2)和Bi_(4)O_(5)Br_(2),5-TB-9具有更强的载流子分离和传输能力.通过紫外-可见漫反射光谱和莫特肖特基曲线表征了材料的导带和价带位置,并结合电子自旋共振和原位XPS,证实了TiO_(2)/Bi_(4)O_(5)Br_(2)2中S-scheme的电荷转移途径.优化后的异质结光催化剂5-TB-9,在12min内对在17L密闭空间内10ppmH,S表出较高的去除效率(>99%).同时,5-TB-9异质结催化剂具有较高的去除动力学速率(r:0.7mmol·h^(-1)·g^(-1))、特定清洁空气输送率(SCADR:5554L·h^(-1)·g^(-1))和量子产率(QY:3.24 E-3分子/光子).此外,研究了5-TB-9在不同催化剂用量(25-150mg)、H_(2)S浓度(5-20 ppm)、流速(100-160L min^(-1))和相对湿度(20%-80%)下对H_(2)S的降解效果.循环降解实验表明,所制备的5-TB-9光催化剂在6次循环实验后仍保持�

关 键 词：H_(2)S removal Photocatalysis S-scheme heterojunction RECYCLABILITY 

分 类 号：O64[理学—物理化学]