GREEN CHEMISTRY
·
2020
·Vol. 22
·期 11
·3597-3607
·
IF 9.48
Hai-Qin Xiao,Wen-Hui Zhou,Dong-Xing Kou,Zheng-Ji Zhou,Yue-Na Meng,Ya-Fang Qi,Sheng-Jie Yuan,Qing-Wen Tian,Si-Xin Wu
Cu2ZnSn(S,Se)4 (CZTSSe) solar cells have been receiving considerable attention in recent years, owing to their low cost and toxicity as well as a high abundance of their constituent elements. Solution-based (mainly precursor solution) methods have been widely used in the fabrication of CZTSSe-based thin film solar cells. Though most record solar cells since 2009 have been achieved using solution-based methods, carbonaceous residues are always formed during post deposition treatment (PDT). These carbonaceous residues are detrimental to grain growth of CZTSSe to form large grains. The presence of unwanted small grain layers will increase the series resistance and reduce the fill factor of the solar cell, thus consequently decreasing the efficiency of CZTSSe solar cells. Herein, we propose “green” supercritical carbon dioxide (SCCO2) treatment to overcome the challenge of carbonaceous residues. FT-IR, SEM, XRD and Raman characterization studies were used to confirm the reduction of carbonaceous residues in CZTSSe films. The solar cell fabricated from a selenized CZTSSe precursor film with SCCO2 treatment under optimal conditions showed the best conversion efficiency of 11.23% (VOC = 0.456 V, JSC = 36.6 mA cm−2, FF = 67.1%). To the best of our knowledge, this is the first report on boosting the efficiency of solution-based CZTSSe solar cells by using SCCO2 treatment. In addition, this unique SCCO2 treatment may also bring forth new ideas for other solution-based optoelectronic devices.
研究领域:
材料科学
·
太阳能
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Nanxin Zheng,Jingyi Zhu,Zhaozhong Yang,Xiaogang Li,Qi Li,Yiping Wen,Gang Chen,Hao Su
It is generally believed that ionic/zwitterionic surfactants have strong interactions with each other. However, our experiments found that nonionic/ zwitterionic surfactants exhibit strong synergistic effects, which differs from the previous understanding. In this study, a scCO 2 foam system stabilized by the synergistic action of alkyl glucoside (APG-10, nonionic surfactant) and erucamide propyl betaine (EAB, zwitterionic surfactant) was constructed. Through the measurement of drainage and coarsening characteristics, surface properties, bulk rheological properties, dynamic light scattering (DLS) and Cryo-scanning electron microscopy (SEM), the stabilizing mechanism of the synergistic action of APG-10 and EAB was revealed for the first time at the macro and micro levels. The results indicate that APG10 and EAB exhibit mixed adsorption at the interface, resulting in a denser molecular arrangement at the interface and enhancing the foaming ability. At 80℃ and 8 MPa, compared to the EAB foam system, the drainage half-life of the EAB+APG-10 system increased by 276.9 %, and the Ostwald ripening rate decreased by 62.4 %. Rheological studies have shown that the zero shear viscosity of the EAB+APG-10 system is 6837.8 mPa·s, with an increase of 44.4 % compared to the EAB system at 80℃. This is believed to be mainly due to the binding of APG-10 to the micellar structure to enhance the entanglement strength of the micelles , aiding in suppressing the expulsion and deformation of foam bubbles. Additionally, the mixed system exhibits larger G’ and E’, effectively suppressing the expansion and contraction of the liquid film . Finally, the sizes and distributions of micellar aggregates were measured by DLS and Cryo-SEM, confirming the presence of wormlike micelles and their distribution within the liquid film. The results of this work provide theoretical support for the development and application of the novel VES-scCO 2 foam fracturing fluid system, which contributes to the efficient extraction of unconventional oil and gas.
研究领域:
石油工程
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2023
·
IF 13.3
Hao Liu,Biao-Qi Chen,Chang-Yong Li,Cun-Jiong Fang,Ranjith Kumar Kankala,Shi-Bin Wang,Ai-Zheng Chen
2D MXene-Ti 3 C 2 T x holds great promise in various electronic applications, especially for electromagnetic interference (EMI) shielding devices and supercapacitors. Ti 3 C 2 T x synthesis typically involves the use of hazardous fluorine-containing chemicals that can result in the formation of inert fluoride functional groups on the surface of Ti 3 C 2 T x , severely degrading its properties and posing a threat to the performance of electron transfer among electrical devices. Herein, a supercritical carbon dioxide-based ternary solution (scCO 2 /DMSO/HCl) to produce fluoride-free Ti 3 C 2 T x in mild conditions (via 0.5 m HCl, 20 MPa, 32 °C) is reported. The fluorine-free Ti 3 C 2 T x films electrode presents an excellent gravimetric capacitance of 320 F g −1 at 2 mV s −1 in 1 m H 2 SO 4 . Besides, it is demonstrated that fluorine-free Ti 3 C 2 T x films exhibit outstanding EMI shielding efficiency of 53.12 dB at 2.5 µm thickness. The findings offer a mild and practical approach to producing fluoride-free Ti 3 C 2 T x and open opportunities for exploring MXenes’ potential applications in various fields.
研究领域:
材料科学
·
电子工程
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Nanxin Zheng,Jingyi Zhu,Zhaozhong Yang,Zhiqiang Jiang,Xiaogang Li,Liehui Zhang,Qi Li,Yiping Wen
Worm-like micelles have been recognized as “living polymers,” and their outstanding physicochemical properties provide unique advantages in improving foam stability. Recently, the use of pseudo-Gemini surfactants to create worm-like micelles has garnered substantial attention because of their cost-effectiveness and high performance. However, there is a dearth of research on the key properties of scCO 2 foam stabilized by pseudo-Gemini surfactants and the mechanism behind their stabilizing effect. To address this gap, a scCO 2 foam system stabilized by worm-like micelles was constructed using pseudo-Gemini surfactants. Through a combination of surface properties, bulk rheology, dynamic light scattering (DLS), and cryo-scanning electron microscopy (Cryo-SEM) measurements, the synergistic effect and foam stabilization mechanism of oleic amidopropyl betaine (OAB) and alpha-olefin sulfonate sodium (AOS) were investigated. The results confirmed the formation of pseudo-Gemini surfactants in the mixed system (OAB + AOS), with superior surface activity compared with individual surfactants. Furthermore, the assembly parameter P = 0.498, determined through interfacial parameter analysis, indicated the self-assembly of worm-like micelles in the mixed system. The rheological properties of the foam liquid, as well as foam drainage, and coarsening experiments showed that the presence of worm-like micelles increased the elasticity of the liquid film, impeding the contraction and expansion of the foam. This resulted in a 145 % increase in the liquid drainage half-life of the scCO 2 foam and a 19.3 % reduction in the diffusion rate of scCO 2 in the liquid film. Further evidence from DLS and Cryo-SEM confirmed the formation of robust worm-like micelle structures in the OAB + AOS mixed system, enhancing the ability of the liquid film to withstand external disturbances. This study is crucial for advancing the existing understanding of pseudo-Gemini surfactants in terms of improving foam performance and designing effective small-molecule foam fracturing fluids.
研究领域:
化学工程
·
材料科学
·
表面化学
✓ 已验证
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Jingyi Zhu,Yufeng Long,Nanxin Zheng,Zhaozhong Yang,Liangping Yi,Xiaogang Li,Hailong Chen
With oil and gas exploration continuing to progress, pseudo-gemini surfactants have gained widespread attention due to their superior performance. However, research on the suspension mechanism and key performance of scCO 2 foam constructed with pseudo-gemini surfactants under high temperature and pressure conditions remains lacking. To tackle this issue, an scCO 2 foam system was constructed based on pseudo-gemini surfactants. The testing methods such as interfacial characteristics, bulk rheology, dynamic light scattering (DLS), and cryogenic scanning electron microscopy (Cryo-SEM), the cooperative foam-stabilizing effect of sodium alcohol ether sulphate (AES) and oleic amidopropyl betaine (OAB) was studied, revealing the proppant suspension mechanism under high temperature and pressure conditions. Using this system as the working fluid for fracturing, its proppant suspension performance, as well as its potential for core matrix damage, was studied. The findings demonstrated that the pseudo-gemini surfactant formed in the mixed system exhibited better surface activity. The assembly parameter P = 0.487, obtained from interfacial parameter evaluation, suggested that micelles were self-assembled within the mixed system. Foam drainage experiments and rheological measurements showed that the wormlike micelles enhanced the elastic response of liquid film, preventing the deformation of foam liquid film, thereby extending the foam drainage half-life by 60 %. DLS and Cryo-SEM experiments verified that the OAB + AES system formed a robust micelle structure, improving the interference resistance of the liquid film. The OAB + AES system, facilitated by micelle formation, slowed down foam drainage and coarsening, slowed the reduction of Plateau borders, and maintained the nodes. Simultaneously, it reduced the impact of gas diffusion on the liquid film structure, improved the stability of spatial distribution of Plateau borders and nodes, increased the foam’s force on the proppants, delayed the settling of proppants. Additionally, under scCO 2 conditions, the proppant settling rate was 3.47 cm/min, meeting industry standards. The foam fracturing fluid exhibited an average reservoir damage rate of just 7.42 %, demonstrating good applicability to reservoirs. This study holds significant importance for advancing VES-scCO 2 foam fracturing fluids and expanding their applications in fracturing operations.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CELLULAR POLYMERS
·
2022
·
IF 1.786
Ke Wang,Ya-qiong Huang,Xiao-han Cheng,Jen-taut Yeh
The micro foaming performance, moisture resistance and dynamic viscosity of scCO2-aid glutaraldehyde/hexametaphosphate/thermoplastic tapioca starch (GA/SHMP/TOS) foams were considerably improved by proper NaOH treatment. The expansion ratio, resilience rate, dynamic viscosity values of these NaOH modified foams improved to a maximum, as the time for NaOH treatment approached a proper value. The dynamic viscosity, expansion ratio and resilience rate of the scCO2-aid GA/SHMP/TOS foams modified using 110 atm scCO2-pressure, the proper alkali treatment time, SHMP loading and varying montmorillonite (MMT) loadings improved further, as their MMT loadings approached a proper value of 2.5 part per hundred parts of tapioca starch (PHTOS). Relatively large dynamic viscosity (7.1x104 Pa·s), extremely large expansion ratio (∼75), cell density (1.1x109 cells/cm3) and/or resilience rate (∼80%) were acquired for the scCO2-aid GA/SHMP/TOS/MMT foam modified using the proper alkali treatment time and MMT loading. Thermal analyses results showed that crystallization onset temperatures and crystallization rates of scCO2-aid GA/SHMP/TOS/MMT foams modified using the proper alkali treatment time and varying MMT loadings improved to a highest value by adding 2.5 PHTOS of MMT nano-platelets. Possible reasons accounting for the considerably improved micro foaming performance of scCO2-aid GA/SHMP/TOS/MMT foams modified using the proper alkali treatment time and MMT loading are proposed in this study.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Shuang Yang,Chuanxian Li,Fei Yang,Xiaoteng Li,Guangyu Sun,Bo Yao
For the pipeline transportation of waxy crude oil, pour point depressants (PPDs) have been developed and used to improve its flowability at low temperature. As supercritical CO2 (scCO2) flooding becomes a common technique to improve oilfield recovery, how the sensitivity of PPD changes due to the degassed crude oil treated by CO2 should be studied. In this work, the effect of scCO2 extraction on the performance of EVA in improving the flowability of Changqing degassed crude oil is investigated by means of a self-developed scCO2 treating equipment, SARA/HTGC analysis, SEM analysis, pour point test, rheological measurement, asphaltene precipitation test, particle size analysis, DSC test, and microscopic observation. The results show that without EVA addition, scCO2 extraction aggravates the flowability of the crude oil at low temperature. The scCO2 extraction extracts light components from asphaltene aggregates causing asphaltenes to precipitate, which inhibits the asphaltenes on playing a role as the natural PPD. As a result, it leads to the formation of smaller needle-like wax crystals with large amount, worsening the flowability of the crude oil. When the EVA is present, however, scCO2 extraction favors the functioning of EVA on improving the flowability of the crude oil at low temperature. The addition of EVA can slightly enhance the solubility of wax molecules thus decreasing the crude oil WAT to some extent, while can significantly change the morphology of precipitated wax crystals from small needle-like to agglomerated clusters, thus improving the flowability of the crude oil. Because of the synergistic effect of EVA and asphaltene aggregates after scCO2 extraction, a more compact EVA–asphaltene–wax ternary crystal structure will form thus further decreasing the pour point, elastic modulus, and equilibrium viscosity at low temperature.
研究领域:
石油工程
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）