查找使用阿拉丁产品的科研文献

Rational design of Bi2Sn2O7/Bi5O7I S-scheme heterojunction for visible photocatalytic oxidation of emerging pollutants

Haidong Luo,Shengjiang Zhang,Fozia Batool,Suhang Chen,Fengqi Zhao,Kangzhen Xu

The construction of an S-scheme heterostructure is considered as a promising strategy for enhancing photocatalytic performance. Herein, a three-dimensional Bi 5 O 7 I (BOI) microsphere decorated with Bi 2 Sn 2 O 7 (BSO) nanoparticles was prepared for the first time via a simple ultrasonic-assisted electrostatic self-assembly strategy and used for the degradation of 2,4-dinitrophenylhydrazine. 3 wt% Bi 2 Sn 2 O 7 /Bi 5 O 7 I has the highest degradation activity (93.7 %), with an apparent rate constant of 0.0848 min −1 , which is 2.55 times that of the original Bi 5 O 7 I (0.0333 min −1 ). Moreover, the optimal binary heterojunction photocatalyst has good reusability and universal applicability. The results of cyclic voltammetry tests clarify that the optimal photocatalyst can provide more surface reactive sites. The results of radical trapping experiments and electron spin resonance indicate that holes (h + ) and superoxide radicals are the main active radicals in the degradation process of 2,4-dinitrophenylhydrazine. Photoelectrochemical and photoluminescence confirm that 3 wt% Bi 2 Sn 2 O 7 /Bi 5 O 7 I composites exhibit the highest separation rate of photogenerated carriers. Finally, based on the results of experimental studies and theoretical calculations, the S-scheme charge transfer path on Bi 2 Sn 2 O 7 /Bi 5 O 7 I composite is determined. This work provides a new perspective on how to design high-performance S-scheme bismuth oxyhalide-based heterojunction photocatalysts for solar energy conversion.

Rational Design of FeCo-S/Ni2P/NF Heterojunction as a Robust Electrocatalyst for Water Splitting

Pinghua Chen,Yirou Wu,Xuan Guo,Mengxue Wang,Cong Yu,Hualin Jiang,Weiqiang Zhou,Guanghui Wu,Jianan Yan

The rational design of nonnoble-metal-based catalysts with high electroactivity and long-term stability, featuring controllable active sites, remains a significant challenge for achieving effective water electrolysis. Herein, a heterogeneous catalyst with a FeCo-S and Ni2P heterostructure (denoted FeCo-S/Ni2P/NF) grown on nickel foam (NF) was synthesized by a solvothermal method and low-temperature phosphorization. The FeCo-S/Ni2P/NF catalyst shows excellent electrocatalytic performance and stability in alkaline solution. The FeCo-S/Ni2P/NF catalyst demonstrates low overpotentials (η) for both the hydrogen evolution reaction (HER) (49 mV@10 mA cm–2) and the oxygen evolution reaction (OER) (279 mV@100 mA cm–2). Assembling the FeCo-S/Ni2P/NF catalyst as both cathode and anode in an electrolytic cell for overall water splitting (OWS) needs an ultralow cell voltage of 1.57 V to attain a current density (CD) of 300 mA cm–2. Furthermore, it demonstrates excellent durability, significantly outperforming the commercial Pt/C∥IrO2 system. The results of experiments indicate that the heterostructure and synergistic effect of FeCo-S and Ni2P can significantly enhance conductivity, facilitate mass/ion transport and gas evolution, and expose more active sites, thereby improving the catalytic activity of the electrocatalyst for the OWS. This study provides a rational approach for the development of commercially promising dual-functional electrocatalysts.

Rationally designed CaTiO3/Mn0.5Cd0.5S/Ni3C S-scheme/Schottky integrated heterojunction for efficient photocatalytic H2 evolution

Hua Lv,Chayuan Zhou,Qinhui Shen,Yuanfang Kong,Baoliang Wan,Zhiyun Suo,Gongke Wang,Guangtao Wang,Yumin Liu

Developing effective photocatalysts to achieve stable and efficient solar-induced hydrogen production remains a significant challenge due to rapid photocarrier recombination and sluggish hydrogen evolution kinetics. Here, a multi-interfacial engineering strategy involving the decoration of metallic Ni 3 C onto CaTiO 3 /Mn 0.5 Cd 0.5 S was proposed to create an S-scheme/Schottky hybrid heterostructure with multiple carrier transport paths for effective photocatalytic H 2 production. Exploiting the synergy between S-scheme heterojunction and Schottky barrier, the engineered ternary CaTiO 3 /Mn 0.5 Cd 0.5 S/Ni 3 C hybrid heterojunction exhibits outstanding photostability and significantly enhanced hydrogen evolution activity of 79.1 mmol g -1  h −1 , which was about 4.55, 3.22 and 2.59 times greater than Mn 0.5 Cd 0.5 S, Mn 0.5 Cd 0.5 S/Ni 3 C, and CaTiO 3 /Mn 0.5 Cd 0.5 S, respectively. By creating an S-scheme heterojunction between CaTiO 3 and Mn 0.5 Cd 0.5 S, accompanied by a robust internal electric field (IEF), spatial charge separation can be effectively accelerated while ensuring the simultaneous preservation of highly active electrons and holes. Meanwhile, Ni 3 C nanoparticles, acting as a Schottky-junction H 2 generation cocatalyst, can efficiently trap the photoinduced electrons to establish multiple charge transfer channels and supply ample active sites for photoreduction reaction, thereby further optimizing the hydrogen generation kinetics. The integration of a Schottky barrier and S-scheme heterojunction in this research is expected to offer new perspectives for designing other highly effective hybrid catalysts for solar-to-hydrogen fuel conversion.

Selective oxidation of ammonia nitrogen to nitrogen gas by S-doped carbon nanotubes activated persulfates

Hanling Jiang,Yuting Chen,Aijuan Zhou,Xiaobo Gong,Juanying Yang,Jingwen Wang,Yong Liu

The selective oxidation of ammonia nitrogen (NH 4 + -N) to dinitrogen (N 2 ) by persulfates (PS)-based advanced oxidation processes (SR-AOPs) without the input of light or electrons is desired, but presents enormous challenges. In this study, S-doped carbon nanotubes (SCNTs) were prepared via a high-temperature sintering process and used to activate PS for NH 4 + -N oxidation in the presence of magnesium oxide (MgO). Compared with pristine carbon nanotubes (CNTs), SCNTs improved the N 2 selectivity of NH 4 + -N oxidation by SR-AOPs, which was attributed to the lower impedance of SCNTs than that of CNTs, enhancing the direct electron transfer pathway of NH 4 + -N oxidation. In the SCNTs/PS/MgO process, the non-radical pathway dominated the oxidation of NH 4 + -N. When SCNTs/PS/MgO process treated polluted lake water, 84.0% of NH 4 -N removal and 85.8% selectivity towards N 2 were achieved at initial pH of 6, initial NH 4 + -N concentration of 30   mg   N/L, SCNTs dosage of 8   g/L, the mass ratios of SCNTs to PS of 1: 1, and reaction time of 60   min, highlighting its potential for practical applications.

Preparation of S-C3N4/AgCdS Z-Scheme Heterojunction Photocatalyst and Its Effectively Improved Photocatalytic Performance

Yuhong Lin,Zhuoyuan Chen,Chang Feng,Li Ma,Jiangping Jing,Jian Hou,Likun Xu,Mingxian Sun,Dongchu Chen

In this study, S-doped graphitic carbon nitride (S-C3N4) was prepared using the high-temperature polymerization method, and then S-C3N4/AgCdS heterojunction photocatalyst was obtained using the chemical deposition method through loading Ag-doped CdS nanoparticles (AgCdS NPs) on the surface of S-C3N4. Experimental results show that the AgCdS NPs were evenly dispersed on the surface of S-C3N4, indicating that a good heterojunction structure was formed. Compared to S-C3N4, CdS, AgCdS and S-C3N4/CdS, the photocatalytic performance of S-C3N4/AgCdS has been significantly improved, and exhibits excellent photocatalytic degradation performance of Rhodamine B and methyl orange. The doping of Ag in collaboration with the construction of a Z-scheme heterojunction system promoted the effective separation and transport of the photogenerated carriers in S-C3N4/AgCdS, significantly accelerated its photocatalytic reaction process, and thus improved its photocatalytic performance.

Optimizing the p charge of S in p-block metal sulfides for sulfur reduction electrocatalysis

Hua Wuxing,Shang Tongxin,Li Huan,Sun Yafei,Guo Yong,Xia Jingyi,Geng Chuannan,Hu Zhonghao,Peng Linkai,Han Zhiyuan,Zhang Chen,Lv Wei,Wan Ying

Understanding sulfur conversion chemistry is key to the development of sulfur-based high-energy-density batteries. However, unclear relationships between the electronic structure of the catalyst and its activity are the major problem. Here, we provide a direct correlation between the p electron gain of S in p -block metal sulfides and the apparent activation energies ( E a ) for the sulfur reduction reaction (SRR), in particular, Li 2 S n to Li 2 S conversion, which is the rate-determining step of the SRR. The maximum p charge occurs in bismuth sulfide and results in the lowest E a and a high SRR rate in the cathode. Li–S batteries with the Bi 2 S 3 catalyst work steadily at a high rate of 5.0C with a high-capacity retention of ~85% after 500 cycles. A high areal capacity of ~21.9 mAh cm −2 was obtained under a high sulfur loading of 17.6 mg cm −2 but a low electrolyte/sulfur ratio of 7.5 μl mg −1 .

Back Contact Plasma Treatment Enables 14.5% Efficient Solution-Processed CuIn(S,Se)2 Solar Cells

Xinyu Li,Chengfeng Ma,Naiyun Liu,Chunxu Xiang,Shuxia Wei,Weibo Yan,Wei Huang,Hao Xin

Solution-processed chalcopyrite thin film solar cells have made great progress but still lag behind the vacuum-based ones due to inferior absorber quality and non-ideal interfaces. Here, plasma treatment of the molybdenum (Mo) substrate is reported to modify the back interface and improve the efficiency of solution-processed copper indium sulfoselenide (CuIn(S,Se) 2 , CISSe) solar cells. The results show plasma treatment oxides the surface Mo/MoO 2 to high oxidation oxides MoO 3-x (0 ≤ x < 1). The higher surface polarity greatly improves the wettability of the substrate to the precursor solution and results in formation of more compact and uniform precursor film, which grows to void-free larger grains absorber film with better adhesion to the substrate. In addition, the much higher chemical stability of MoO 3-x than Mo significantly reduces the thickness of high resistive MoSe 2 layer. The improved absorber quality and back interface property decreases charge carrier recombination in the absorber and back contact interface, resulting in 14.53% efficiency solution-processed CISSe solar cell, which is improved by 13% compared to device without plasma treatment.

Synthesis of sulfonated chitosan and its antibiofilm formation activity against E. coli and S. aureus

Jianying Huang,Yuhong Liu,Lijun Yang,Fengyan Zhou

A sulfonated chitosan (SCS) was prepared via nucleophilic substitution and characterized by Fourier transform infrared spectroscopy, 1 H and 13 C NMR spectra, gel permeation chromatography, elemental analysis, and thermo gravimetric analysis. The inhibition activities of bacterial adhesion and biofilm formation against E. coli and S. aureus of SCS were assessed in comparison with those of unmodified chitosan hydrochloride (WCS) which was commercially available. The metabolic activity and secretion of exopolysaccharide in biofilms of E. coli and S. aureus were significantly decreased after the treatment of SCS. Scanning electron microscopy and confocal laser scanning microscopy also demonstrated that SCS and WCS at 1MIC concentrations could obviously inhibit the formation of biofilm. Upon the experimental data obtained, it can be concluded that the alkylsulfonation of chitosan could significantly improve efficacy in killing biofilm-embedded bacteria, and the inhibition activities against biofilm formation of E. coli and S. aureus . The exploitation of SCS in this study is helpful to extend the understanding to an alternative to antibiotics and chemical preservatives in food and medicine fields.

Synthesis, characterization, and DFT studies of a new chiral ionic liquid from (S)-1-phenylethylamine

Shuya Cui,Tao Wang,Xiaoli Hu

A new chiral ionic liquid was synthesized from (S)-1-phenylethylamine and it was studied by IR, Raman, polarimetry, NMR and X-ray crystal diffraction. Its vibrational spectral bands are precisely ascribed to the studied structure with the aid of DFT theoretical calculations. The optimized geometries and calculated vibrational frequencies are evaluated via comparison with experimental values. The vibrational spectral data obtained from IR and Raman spectra are assigned based on the results of the theoretical calculations by the DFT-B3LYP method at 6-311G(d,p) level. The computed vibrational frequencies were scaled by scale factors to yield a good agreement with observed experimental vibrational frequencies.   The vibrational modes assignments were performed by using the animation option of GaussView5.0 graphical interface for Gaussian program.

Glutathione S-Transferase Genes are Involved in Lambda-Cyhalothrin Resistance in Cydia pomonella via Sequestration

Chao Hu,Ji-Yuan Liu,Wei Wang,David Mota-Sanchez,Shun He,Yu Shi,Xue-Qing Yang

Pest management is mostly accomplished by the use of insecticides. However, the overuse of insecticides has led to the development of resistance. Glutathione S-transferases (GSTs) are vital detoxification enzymes involved in insecticide resistance in insects. In this study, we report the involvement of GSTs in insecticide resistance to lambda-cyhalothrin in Cydia pomonella, a globally quarantined fruit pest. A total of 25 GST, including 22 cytosolic genes and 3 microsomal genes, are identified from the genome database of C. pomonella. These cytosolic genes are further classified into six classes, including four in delta, eight in epsilon, three in omega, three in sigma, one in theta, and one in zeta class, as well as two unclassified genes. The real-time quantitative polymerase chain reaction (RT-qPCR) shows that the majority of these genes are mainly expressed throughout the larval stage and in the midgut of the fourth-instar larvae. Exposure to an LD10 dose of lambda-cyhalothrin resulted in the upregulation of 17 GST genes. Moreover, mRNA levels of most GST genes, with the exception of CpGSTe6, CpGSTd2, CpGSTd4, and CpGSTz1, are considerably higher in a lambda-cyhalothrin-resistant population (ZW_R) than those of susceptible strains. Recombinant CpGSTd1, CpGSTd3, CpGSTe3, and CpGSTs2 can bind and metabolize lambda-cyhalothrin, with the highest metabolic rate observed for CpGSTd3 but no metabolite(s) was detected, supporting the role of GSTs in sequestration of lambda-cyhalothrin. Molecular dynamics simulation analysis indicates that key residues of hydrophobic pocket-derived lipophilic energy S(lipo) interactions with a hydrophobic pharmacophore of lambda-cyhalothrin are crucial for metabolism by CpGSTd3 and further lead to resistance. Our study is the first to experimentally confirm the involvement of GSTs in lambda-cyhalothrin resistance via sequestration and provides new insights into resistance management in C. pomonella.

MoO2 Sacrificial Layer for Optimizing Back Contact Interface of Cu2ZnSn(S,Se)4 Solar Cells

Bin Xu,Xiaoshuang Lu,Chuanhe Ma,Yulin Liu,Ruijuan Qi,Rong Huang,Ye Chen,Pingxiong Yang,Junhao Chu,Lin Sun

Supramolecularly engineered S-scheme SubPc-Br/MoS2 photocatalyst nanosheets for enhanced photocatalytic degradation of antibiotics

Bing Wang,XuXia Zhang,RuiQing Zhang,Zhuo Li,Bin Tian,HaiXia Ma,Zheng Zheng,Bo Zhou,MengTing Ji,ChuanHui Shi,Hong Hao

Developing a simple, low-cost, high-yield, and controllable strategy for preparing various functionalized MoS 2 -based composite materials remains a challenge. This study innovatively utilizes boron subphthalocyanine bromide (SubPc-Br) as a photosensitizer, which self-assembles on MoS 2 via intermolecular π-π stacking, creating a SubPc-Br/MoS 2 organic–inorganic semiconductor system. This addresses a research gap, employing subphthalocyanines as MoS 2 sensitizers. The SubPc-Br/MoS 2 heterojunction exhibited excellent photocatalytic activity for the degradation of antibiotics in water under solar irradiation. The rate constants for the photocatalytic degradation of CTC and CIP by SubPc-Br/MoS 2 were 4.66 and 5.93 times higher than those of pristine MoS 2 , respectively. The significant improvement in photocatalytic performance is attributed to the efficient charge separation and transfer induced by the unique S-Scheme charge transfer mechanism, which has been verified by different theoretical and experimental results. We demonstrate that the photochemical activity of O 2 molecules adsorbed on MoS 2 (1   0   0) is site-sensitive, with O 2 preferentially adsorbing on the Mid-site location with higher electron transport capability. This study provides a new perspective for enhancing photocatalytic performance by constructing an artificial photosynthetic system with an S-scheme heterojunction.