Asia-Pacific Journal of Chemical Engineering
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2024
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IF 1.4
Jianke Tang,Qiaoling Li,Rongqian Meng,Yanfeng Xue,Shengjian Zhang,Shengjuan Shao
Using the prepared Ag 3 PO 4 /WO 3 ·H 2 O composite as the matrix, AgI nanoparticles were introduced onto the surface of Ag 3 PO 4 to construct AgI/Ag 3 PO 4 /WO 3 ·H 2 O ternary heterojunction photocatalysts. The ternary composite photocatalysts exhibited higher photocatalytic degradation activities for rhodamine B (RhB) and tetracycline hydrochloride (TCH) than those of binary Ag 3 PO 4 /WO 3 ·H 2 O and AgI/WO 3 ·H 2 O photocatalysts and individual AgI, Ag 3 PO 4 , and WO 3 ·H 2 O photocatalysts. After exposure to visible light for 12 and 24 min, the removal efficiencies of RhB and TCH by the S2-50% photocatalyst (50% molar percentage of AgI to Ag 3 PO 4 ) reached 98.0% and 85.3%, respectively. After four degradation cycles, the removal efficiency of RhB by S2-50% remained at 93.2%, significantly surpassing that of the Ag 3 PO 4 /WO 3 ·H 2 O photocatalyst. The enhanced photocatalytic performance of the AgI/Ag 3 PO 4 /WO 3 ·H 2 O photocatalyst is primarily attributed to the formation of Z-scheme/conventional Type II heterojunctions, which facilitate spatial separation of the photogenerated electrons and holes while maintaining the strong reductive capabilities of electrons in the AgI conduction band.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 62
·39089-39095
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IF 3.108
Ying-Ying Shao,Wei-Dong Ye,Chun-Yan Sun,Chu-Lin Liu,Qi Wang
As typical persistent organic pollutants, polybrominated diphenyl ethers (PBDEs) have aroused high environmental concern because of their toxicity and recalcitrant degradation. Here we report the visible-light-induced degradation of PBDEs with AgI–TiO2 (>420 nm). A series of nano-structured AgI–TiO2 particles were synthesized by a deposition–precipitation method and characterized by SEM, TEM, XRD, XPS, BET and UV-Vis-DRS. The AgI–TiO2 hybrids showed high efficiency for degradation of PBDEs and excellent photostability in cyclic run experiments. The absorbance intensity and absorption ability of AgI–TiO2 hybrids and the properties of the solvents were found to greatly influence the efficiency of degradation of PBDEs. The 0.2-AgI–TiO2 (the mass ratio of Ag to P25 was about 20%) in CH3OH solution presented the highest reaction rate with 0.29 ± 0.02 h−1. Most interestingly, mechanistic pathways in the degradation of PBDEs were different under UV and visible light. Unlike the common single-electron transfer in the UV-TiO2 system, the debromination mechanism in the visible light/AgI–TiO2 system showed multi-electron transfer. The analysis of products showed that many different lower brominated congeners simultaneously appeared under visible light rather than being stepwise formed under UV. This implies that the special structure of AgI–TiO2 performs remarkably enhanced electron transfer, multi-electron transfer, and results in high photocatalytic activity. This research may provide a green and efficient method to remove halogenated pollutants by using visible light.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2019
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IF 6.361
Qi Wang,Chenlu Zhang,Hong Wu,Qiaoyuan Gao,Ran Duan,Chuncheng Chen
Bi 2 O 2 CO 3 was co-decorated by β-phase AgI and Bi 2 O 3 forming visible-light-active AgI(β)/Bi 2 O 3 (β)-Bi 2 O 2 CO 3 composite via simply calcining AgI/Bi 2 O 2 CO 3 . The calcination temperature and time played vital role in regulating the structure as well as photocatalytic performance. Optimal AgI(β)/Bi 2 O 3 (β)-Bi 2 O 2 CO 3 was obtained after 325 ◦ C calcination for 2 h with 5% AgI. The ratio of Bi 2 O 3 to Bi 2 O 2 CO 3 was estimated to be ca. 3:1 on the catalyst surface. The transformation process for n -type Bi 2 O 2 CO 3 to p-type Bi 2 O 3 (β) was monitored and verified by flat band potential measurements. Due to the presence of p-n junctions between p-type Bi 2 O 3 (β), n -type AgI(β) and Bi 2 O 2 CO 3 , the optimized ternary composite displayed enhanced photocurrent density and reduced charge transfer resistance, which were beneficial for photocatalytic applications. Despite of decreased specific surface area, dramatically enhanced photocatalytic performance can be observed for simultaneous removal of Cr(VI) and phenol . For example, the estimated k Cr(VI) and k phenol on AgI(β)/Bi 2 O 3 (β)-Bi 2 O 2 CO 3 were 3.3 and 2.2 times relative to those on uncalcined AgI/Bi 2 O 2 CO 3 , respectively. The optimized composite also displayed good stability in 4 successive cyclic runs.
研究领域:
材料科学
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环境科学
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DOI
PubMed
高影响因子
ChemElectroChem
·
2020
·Vol. 7
·期 7
·1567-1572
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IF 4.154
Wanchun Qiao,Ang Qiao,Yunhang Tao,Shaoxuan Gu,Yuanzheng Yue,Haizheng Tao
Graphical Mill and heat : A chemo-mechanical milling process is used to prepare a highly conductive amorphous 0.5AgI ⋅ 0.5 Ag 3 PS 4 conductor. The mechanisms of the enhancement in ionic conductivity for the present 0.5AgI ⋅ 0.5 Ag 3 PS 4 amorphous powder together with the heat-treated one are discussed. Through a chemo-mechanical milling process, we prepared a highly conductive (1.1×10 −3 S ⋅ cm −1 ) amorphous 0.5AgI ⋅ 0.5 Ag 3 PS 4 conductor, which is much higher than that of pure amorphous Ag 3 PS 4 (8.5×10 −4 S ⋅ cm −1 ). Detailed structural characterizations indicate that compared to the ionic conductivity of the amorphous Ag 3 PS 4 conductor, the enhancement can be ascribed to the formation of mixed polymeric anions {[PS 4 ] m I n } around Ag + ions. Through heat-treatment at 370 °C for 20 minutes, the room temperature ionic conductivity of the 0.5AgI ⋅ 0.5 Ag 3 PS 4 conductor is further enhanced by about 4 times. This enhancement can be ascribed to the following two aspects: 1) the existence of residual amorphous phase with higher ionic conductivity; 2) the connection of the fast ionic conductive interfaces between the deposited Ag 7 PS 6 nano-crystals and the residual amorphous phase. This work reveals the key roles of both disorder and interface in improving the ionic conductivity of solid-state electrolytes.
研究领域:
材料科学
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固态离子学
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高影响因子
ACS Applied Materials & Interfaces
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2019
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IF 8.456
Libo Fan,Songzi Liu,Yan Lei,Ruijuan Qi,Lijia Guo,Xiaogang Yang,Qingbo Meng,Qilin Dai,Zhi Zheng
The utilization of quantum dots (QDs) to improve the performance of perovskite solar cells is attracting much attention due to their unique optical and electronic properties. Most of QDs have to be prepared in advance and then incorporated into the perovskite hosts, which could not ensure the maintenance of their QD characteristics. In this work, we intelligently developed an in situ preparation strategy to disperse AgI QDs homogeneously in the perovskite host for the MAPbI3:AgI(QDs) cross-blended layer directly on indium tin oxide (ITO) via a common and convenient spin-coating process. We combine transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman techniques to demonstrate the cross-blended MAPbI3:AgI(QDs) structure in the final perovskite devices. Furthermore, a series of simply inverted ITO/MAPbI3:AgI(QDs)/PCBM/Ag devices have been designed and fabricated. The photovoltaic performance of these solar cells shows significantly improved short-circuit current density (Jsc) and a champion power conversion efficiency of 16.41% even without a hole transport layer. The current technique induced the crystal growth toward high-quality perovskite films with a homogeneous structure, good crystallinity, less grain boundaries and defects, increased optical path length, and uniform thickness for better solar cell performance. Besides, the impact of the current strategy also lies in an accommodation effect of the hole collection at the ITO side induced by AgI QDs, which modifies the Fermi level of perovskite films, leading to significantly decreased level difference in the Fermi level/work function between the perovskite layer and ITO substrates by ultraviolet photoelectron spectra analysis. More importantly, the charge carrier dynamics of such novel MAPbI3:AgI(QDs) structures were also scrutinized by transient photovoltage analysis.
研究领域:
材料科学
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光伏技术
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DOI
PubMed
高影响因子
ACS Omega
·
2019
·
IF 2.584
Zhongyi Jiao,Zhendong Liu,Zhen Ma
Novel AgI/Ag2Mo2O7 heterojunctions were prepared by reacting Ag2Mo2O7 microrods with an aqueous KI solution at room temperature. The composite materials, compared with neat AgI and Ag2Mo2O7, showed much higher activities in the photocatalytic degradation of aqueous rhodamine B, methyl orange, tetracycline hydrochloride, and levofloxacin solutions under visible-light irradiation. The structures, morphologies, and other physicochemical properties of AgI, Ag2Mo2O7, and AgI/Ag2Mo2O7 composites were studied via various characterization techniques. The active species involved in the photocatalytic process were examined via radical-capturing experiments and electron spin resonance. Superoxide anion radicals (•O2–) and photogenerated holes (h+) were found to be the main active species. Photocatalytic mechanisms were proposed and reasons for the enhanced photocatalytic activity were explained.
研究领域:
材料科学
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环境科学
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化学
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PubMed
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 7
·4083-4090
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IF 11.301
Jin Liu,Xingcai Zhang,Qian Zhong,Jun Li,Hongzhang Wu,Bo Zhang,Lin Jin,Hua Bing Tao,Bin Liu
Semiconductor p–n junction engineering plays an indispensable role in developing highly efficient photocatalysts for energy conversion and environmental remediation. Herein, a novel AgI/Bi2Ga4O9 p–n junction photocatalyst is successfully constructed by an electrostatic self-assembly approach. Photoelectrochemical characterization together with density functional theory calculations shows that the formation of a p–n junction at the AgI/Bi2Ga4O9 interface favors separation and transfer of photogenerated charge carriers. The ˙O2− generated by 25%-AgI/Bi2Ga4O9 reaches a concentration of 18.8 μmol L−1 after 60 min of irradiation, which is 3.3 and 12.5 times higher than that generated by AgI and Bi2Ga4O9, providing 25%-AgI/Bi2Ga4O9 with greatly enhanced photocatalytic activity toward Acid Red 1 and metronidazole degradation. Our work provides a novel strategy for designing highly efficient photocatalysts for a wide range of energy and environmental applications.
研究领域:
材料科学
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环境科学
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能源科学
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Zhangwei Sun,Yuhao Qi,Kaile Wang,Jiaming Li,Xiaoyu Qiu,Yunhe Zhao,Li Guo
In this study, we developed an in-situ deposition method to load small-sized AgI nanoparticles as an oxidative photocatalyst (OP) onto phosphorus (P) and potassium (K) co-doped two-dimensional porous g-C 3 N 4 (PK-CN-N) as a reductive photocatalyst (RP), forming an S-scheme heterojunction photocatalyst AgI/PK-CN-N. PK-CN-N achieved morphology control and element doping, leading to surface functionalization and heterostructure formation for the AgI/PK-CN-N photocatalyst. Notably, the 50AgI/PK-CN-N composite demonstrated an approximately 95 % removal efficiency for RhB within 30 minutes, 17.6 times higher than pure g-C 3 N 4 , surpassing most reported g-C 3 N 4 -based photocatalysts. The enhanced photocatalytic efficiency is attributed to the surface modification strategy and heterostructure formation of g-C 3 N 4 , which broadens the visible light response range, increases the number of active sites, improves the separation of photogenerated electron-hole pairs, and enhances REDOX capabilities. The band structure of the composite was elucidated through Mott-Schottky analysis and UV–vis DRS. The formation of the AgI/PK-CN-N S-scheme heterojunction and its charge transfer mechanism was confirmed through XPS, band structure analysis, KPFM, and EPR spectroscopy. Experimental data confirmed the presence of a strong and effective interface electric field between the two semiconductors, leading to band bending and accelerated charge separation. Additionally, the introduction of small-sized AgI semiconductors enhanced the exposure of the coupling interface, further improving catalytic performance. The reusability and lifespan of the catalyst were also analyzed, showing that after four cycles, the photocatalytic activity remained above 92 %.
研究领域:
材料科学
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环境科学
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高影响因子
Journal of the Taiwan Institute of Chemical Engineers
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2017
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IF 4.217
Junlei Zhang,Zhen Ma
Visible-light-driven photocatalysis for removing industrial dyes and antibiotics in waste water has attracted much interest. New catalysts with enhanced photocatalytic performance have been actively sought. Herein, via a simple sequential precipitation method, AgI nanoparticles were anchored onto micron-sized β-Ag 2 MoO 4 particles to form AgI/β-Ag 2 MoO 4 p–n heterojunctions. These heterojunctions exhibited remarkably upgraded activities in the visible-light-driven photocatalytic degradation of rhodamine B, methyl orange, and tetracycline hydrochloride compared with pristine AgI and β-Ag 2 MoO 4 . The enhanced photocatalytic activity can be mainly attributed to the tight heterojunction structure and well matched energy band that may facilitate the separation and transfer of photogenerated electron–hole pairs. Photogenerated holes (h + ) and superoxide radical anions (•O 2 − ) were found to be the main active species. A possible photocatalytic mechanism was proposed.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Journal of Environmental Chemical Engineering
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2021
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IF 5.909
Fang-Di Wu,Jyh-Cherng Chen,Jia-Peng Hu
A ternary composite photocatalyst with high catalytic activity (TiO 2 /Ti 3 C 2 T x /AgI) was synthesized using the simple solvothermal and coprecipitation methods. The structure, morphology, photoelectric properties, and photocatalytic activity of the prepared materials were studied using various characterization techniques. The composite catalysts TiO 2 /Ti 3 C 2 T x /AgI with different proportions of TiO 2 /Ti 3 C 2 T x to AgI of 10%, 20%, 50%, 70%, and 90% were prepared by varying the amounts of AgNO 3 and KI. Compared to AgI and TiO 2 /Ti 3 C 2 T x , TiO 2 /Ti 3 C 2 T x /AgI demonstrated a superior photocatalytic degradation activity for tetracycline hydrochloride (TCH) under simulated sunlight. The degradation rate of TCH with 70% TiO 2 /Ti 3 C 2 T x /AgI composite photocatalyst reached 97%. The photoluminescence (PL) emission spectra showed that the recombination of photogenerated electrons of 70% TiO 2 /Ti 3 C 2 T x /AgI was effectively inhibited after the formation of AgI, TiO 2 , and Ti 3 C 2 T x heterojunctions . The electrochemical impedance spectroscopy (EIS) indicated that a rapid interfacial charge transfer of the 70% TiO 2 /Ti 3 C 2 T x /AgI composite to the electron acceptors (Ti 3 C 2 T x ). Ti 3 C 2 T x had high conductivity and can effectively accelerate the transfer and separation of photogenerated carriers as a charge medium. Therefore, the enhancement of photocatalytic activity of TiO 2 /Ti 3 C 2 T x /AgI can be attributed to the Z-scheme heterojunction with non-metal Ti 3 C 2 T x as the solid medium. In addition, the trapping agent experiment showed that superoxide radicals, singlet oxygen, and holes were the main active substances in the photocatalytic degradation of TCH by the TiO 2 /Ti 3 C 2 T x /AgI composite.
研究领域:
材料科学
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环境科学
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高影响因子
Nanoscale Research Letters
·
2018
·Vol. 13
·期 1
·1-8
·
IF 3.125
Lu Junlin,Shang Chaoqun,Meng Qingguo,Lv Haiqin,Chen Zhihong,Liao Hua,Li Ming,Zhang Yongguang,Jin Mingliang,Yuan Mingzhe,Wang Xin,Zhou Guofu
A series of novel visible light driven all-solid-state Z-scheme BiOBr 0.3 I 0.7 /Ag/AgI photocatalysts were synthesized by facile in situ precipitation and photo-reduction methods. Under visible light irradiation, the BiOBr 0.3 I 0.7 /Ag/AgI samples exhibited enhanced photocatalytic activity compared to BiOBr 0.3 I 0.7 and AgI in the degradation of methyl orange (MO). The optimal ratio of added elemental Ag was 15%, which degraded 89% of MO within 20 min. The enhanced photocatalytic activity of BiOBr 0.3 I 0.7 /Ag/AgI can be ascribed to the efficient separation of photo-generated electron–hole pairs through a Z-scheme charge-carrier migration pathway, in which Ag nanoparticles act as electron mediators. The mechanism study indicated that ·O 2 − and h + are active radicals for photocatalytic degradation and that a small amount of ·OH also participates in the photocatalytic degradation process.
研究领域:
材料科学
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环境科学
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DOI
PubMed
高影响因子
Materials Today Communications
·
2020
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IF 2.678
Tiantian Zhou,Haonan Zhang,Xiaoming Ma,Xin Zhang,Yuanna Zhu,Aiyu Zhang,Yongqiang Cao,Ping Yang
The AgI/Bi 2 MoO 6 /AgBi(MoO 4 ) 2 (ABM) multi-heterostructure nanosheet composite system for visible-light photocatalysis have been successfully constructed by a simple one-step calcination method. The ABM multi-heterostructure composite photocatalysts exhibited the obviously improved photocatalytic performance than the pristine Bi 2 MoO 6 , AgBi(MoO 4 ) 2 , and AgI for the degradation of both Tetracycline hydrochloride (TC) and Rhodamine B (RhB). The apparent degradation rate for the ABM sample with the highest photocatalytic activity is 5.4 (TC) and 23.4 times (RhB) that of Bi 2 MoO 6 , 4.0 (TC) and 4.9 times (RhB) that of AgBi(MoO 4 ) 2 , and 1.9 (TC) and 2.4 times (RhB) that of AgI, respectively. This ABM sample with the highest activity showed a Bi 2 MoO 6 /AgBi(MoO 4 ) 2 composite nanosheet morphology (lateral size: 1–5 u m, thickness: 90−130 nm) with a large amounts of small AgI nanocrystals (diameter: 2−25 nm) uniformly distributed on the surface of composite sheet. The outstanding performance of the ABM composite photocatalysts should be ascribed to the effective separation of photoinduced electron-hole pairs via the multi-heterostructure in ABM, the enhanced visible-light absorption, as well as the two-dimensional (2D) morphology benefitting to the exposure of plenty of surface reactive sites and significant reduction of migration distances of photogenerated carriers. It is hoped that this facile method for the fabrication of multi-heterostructure in our work could promote and inspire the other multicomponent functional nanomaterials used in the fields of not only photocatalysis, but also solar cells, sensors, catalysis, and so on, in the future.
研究领域:
材料科学
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环境科学
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DOI
高影响因子