CERAMICS INTERNATIONAL
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2023
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IF 5.2
Peng Qiu,Huiyun Wei,Qianming Huang,Meina Yu,Yuyu Hu,Xiaoli Zhu,Heng Liu,Xinhe Zheng
In this work, gallium nitride (GaN) is employed for the first time to modulate the charge dynamics of quantum dot-sensitized solar cells (QDSCs). An ultrathin GaN layer has been coated on the surface of both mesoporous TiO 2 photoanode and quantum dots (QDs) at 240 °C by plasma-enhanced atomic layer deposition (PEALD) approach. It is revealed that there exists a stepped energy level alignment among the as-prepared TiO 2 film, GaN layer and QDs, which accelerates the extraction and collection of photogenerated electrons. Meanwhile, a type-II core-shell QD/GaN structure is formed benefiting from the self-limiting reactions of PEALD, resulting in an enhanced light absorption and a redshift of absorption edge. In addition, the dense GaN layer can also effectively inhibit the reverse transfer of photogenerated electrons from TiO 2 to QDs or electrolyte while improving the connection between TiO 2 and QDs. Ultimately, the QDSCs with a 0.68 nm-thick GaN layer achieve a 29% increase of short-circuit current density and enhanced device efficiency, even with reduced fill factor. This work has shown the multi-functions of GaN in regulating the charge dynamics of QDSCs as well as the potential advantages in replacing TiO 2 as photoanode for electronic extraction and transport.
研究领域:
材料科学
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能源技术
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2025
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IF 21.1
Ziwen An,Qihao Xie,Shaohan Xu,Baoling Niu,Lingzhi Sun,Jingui Zheng,Guohua Zhao
Perfluorooctanoic acid (PFOA), a synthetic persistent and bio-accumulative chemical, has raised global concerns. PFOA oxidation by advanced oxidation technology (AOPs) begins with decarboxylation, followed by CF 2 groups unzipping cycle and C–F cleavage. Since reactive radicals (even •OH) cannot initiate decarboxylation and abundant low-toxicity organics hinders decarboxylation, presents significant challenges for defluorination. We designed a functionalized high-index (201) TiO 2 photoanode (S-TiO 2,201 ) capable of molecular recognition and activation, which switches PFOA adsorption from carboxyl groups to preferential adsorption via the perfluoroalkyl backbone. This adsorption configuration selectively recognizes PFOA and accelerates decarboxylation via direct hole oxidation. In situ electron paramagnetic resonance (EPR) confirmed faster decarboxylation and •OH quantification showed hole utilization efficiency rising from 9.6 % to 39.3 % after functionalization. PFOA was selectively removed from 200 μg/L to 1.2 μg/L with 1000-fold humic acid interference. This work presents a strategy for efficient and selective PFOA removal by precisely modulating its adsorption configuration.
研究领域:
环境化学
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光化学
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材料科学
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水处理技术
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电化学
✓ 已验证
DOI
高影响因子
SOLAR ENERGY
·
2025
·
IF 6.6
Zhen Li,Guizhang Guo,Zhou Yu,Zengyue Ma,Yonggang Lei,Libo Yu,Junke Wang
The use of quantum dots (QDs) to sensitize titanium TiO 2 in photoelectrochemical cells (PECs) for solar-driven water splitting represents a highly promising method for converting solar energy into storable chemical energy in the form of hydrogen. The characteristics and interfaces of the QDs play a crucial role in determining the range of light absorption and the efficiency of charge transport and separation upon photoexcitation. Herein, we build CdS x Se 1-x QDs sensitized TiO 2 photoanodes with different amount of Se source by one-step hydrothermal process using thioglycolic acid (TGA) as bifunctional linker. Our results demonstrate that TGA can both anchor QDs to TiO 2 and decompose S for CdS x Se 1-x QDs preparation. The influence of Se source dosage on PEC performance of CdS x Se 1-x /TiO 2 photoanode has been investigated. UV–vis absorption data shows the increase of Se source can enlarge light response range. X-ray photoelectron spectroscopy, transient open-circuit voltage decay and electron lifetime tests indicate proper thickness of SeO 2 which formed on CdS x Se 1-x QDs has the effect to block charges recombination between CdS x Se 1-x /TiO 2 photoanode and electrolyte, improving the electron lifetime of photogenerated electrons. Consequently, the photoelectrochemical cell (PEC) constructed with a CdS x Se 1-x /TiO 2 photoanode, prepared using 0.8 mmol of selenium source, has achieved a photocurrent density of 14.31 mA cm −2 and a photoconversion efficiency of 15.74 %. These results indicate significant potential for the production of green hydrogen.
研究领域:
材料科学
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纳米技术
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能量转换
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光电化学
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2023
·
IF 12.8
Xing Wang,Mengjun liang,Jiancong Zhang,Xuncai Chen,Mono Zaw,Than Zaw Oo,Nyein Wint Lwin,Su Htike Aung,Yuan Chen,Fuming Chen
High energy consumption and low salt removal rate are key barriers to realizing practical electrochemical seawater desalination processes. Here, we demonstrate a novel solar-driven redox flow desalination device with double photoelectrodes to achieve efficient desalination without electrical energy consumption. The device consists of three parts: one photoanode unit, one photocathode unit, and one redox flow desalination unit sandwiched between the two photoelectrode units. The photoelectrode units include a TiO 2 photoanode and a NiO photocathode sensitized with N719 dye, triiodide/iodide redox electrolyte, and graphite paper integrated electrodes decorated with 3,4-ethylene-dioxythiophene. Two salt feeds are located between two ferro/ferricyanide redox flow chambers. Under light illumination, high-quality freshwater is obtained from brackish water containing different concentrations of NaCl from 1000 to 12,000 ppm with a high NaCl removal rate. The device can work in multiple desalination cycles without significant performance declines. Furthermore, natural seawater with an ionic conductivity of 53.45 mS cm −1 is desalinated to freshwater. This new design opens opportunities to realize efficient and practical solar-driven desalination processes.
研究领域:
环境科学
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材料科学
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化学工程
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太阳能
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）