Pyramid-like CdS nanoparticles grown on porous TiO₂ monolith: An advanced photocatalyst for H₂ production

Du, Jimin,Wang, Huiming,Yang, Mengke,Li, Kaidi,Zhao, Lixin,Zhao, Guoyan,Li, Sujuan,Gu, Xiaolei,Zhou, Yalan,Wang, Le,Gao, Yating,Wang, Weimin,Kang, Dae Joon Pergamon Press 2017 Electrochimica Acta Vol. No.

<P><B>Abstract</B></P> <P>Efficient production of H<SUB>2</SUB> via solar-light-driven water splitting by a semiconductor-based photocatalyst without noble metals is crucial owing to increasingly severe global energy and environmental issues. However, many challenges, including the low efficiency of H<SUB>2</SUB> evolution, low solar light absorption, excited electron–hole pair recombination, and slow transport of photoexcited carriers, must be resolved to enhance the H<SUB>2</SUB> photoproduction efficiency and photocatalyst stability. Here, a two-step method is used to synthesize advanced H<SUB>2</SUB>-generating photocatalysts consisting of pyramid-like CdS nanoparticles grown on a porous TiO<SUB>2</SUB> monolith, which show promising photocatalytic activity for the hydrogen evolution reaction. Furthermore, the stability of the photocatalysts is examined through long-term tests to verify their good durability. Without noble metals as cocatalysts, the photocatalyst can reach a high H<SUB>2</SUB> production rate of 1048.7μmolh<SUP>−1</SUP> g<SUP>−1</SUP> under UV–vis irradiation when the ratio of the CdS nanoparticles to TiO<SUB>2</SUB> is 5mol%. This unusual photocatalytic activity arises from the wide-region light adsorption due to the narrow band gap of CdS, effective separation of electrons and holes due to conduction band alignment at the CdS–TiO<SUB>2</SUB> interface, and favorable reaction sites resulting from the porous structure.</P>

Shelf Life Prediction of ‘Royal Gala’ Apples Based on Quality Attributes and Storage Temperature

Mengke Cao,Dong Wang,Lingyu Qiu,Xiaolin Ren,Huiling Ma 한국원예학회 2021 원예과학기술지 Vol.39 No.3

Phenotypic changes caused by postharvest deterioration of the quality attributes of apples cause substantial economic losses. Thus, strategies for accurate prediction of the shelf life of apples is urgently needed. In each of the three consecutive years from 2016 to 2018, freshly harvested ‘Royal Gala’ apples were stored at 0, 5, 15, and 25°C, respectively. Subsequently, 11 quality attributes were measured at periodic intervals until the end of storage. To screen fewer and more useful indexes, three input datasets were considered: temperature, color value (L*, a*, b*, △E, and C*), weight loss, firmness, titratable acidity, soluble solids content, starch, and reducing ascorbic acid (D1). The key quality attributes were screened by sparse principal component analysis (SPCA) (D2) and correlation analysis (CA) (D3), using shelf life as the output layer of the artificial neural network based on the back propagation (BP ANN) model. The results showed that the correlation coefficients (r) of the predicted and measured shelf life for D1, D2, and D3 were 0.996, 0.997, and 0.993, respectively, while the mean relative errors were 0.071, 0.074, and 0.074, respectively. Meanwhile, the relative percent root mean square (RMS) values were 0.088, 0.092, and 0.112, respectively. The application of SPCA reduced the quality attributes for the input dataset from 12 to 6. Therefore, SPCA-BP ANN was shown to be a useful model for accurate prediction of the postharvest shelf life of ‘Royal Gala’ apples.

Controlled synthesis of nanoplate, nanoprism and nanopyramid-shaped CdSe decorated on porous TiO₂ photocatalysts for visible-light-driven hydrogen evolution

Yang, Mengke,Qian, Yongteng,Du, Jimin,Yuan, Sijie,Wang, Sijia,Zhu, Xinrui,Lin, Xialing,Li, Kaidi,Li, Sujuan,Kang, Dae Joon Elsevier 2018 Ceramics international Vol.44 No.11

<P><B>Abstract</B></P> <P>Herein, we report a successful synthesis of porous TiO<SUB>2</SUB> monoliths decorated with unique nanoplate, nanoprism, and nanopyramid-shaped CdSe particles through a mild selenylation of CdO embedded inside porous TiO<SUB>2</SUB> monoliths via a hydrothermal method in a very controlled manner. Compared with pure TiO<SUB>2</SUB>, as-synthesized CdSe/TiO<SUB>2</SUB> photocatalyst not only enhances light absorption but also leads to a highly efficient charge-carrier separation. Particularly, the nanoplate-shaped 7% CdSe/TiO<SUB>2</SUB> photocatalyst (molar percentages of CdSe to TiO<SUB>2</SUB> is 7:100) exhibits an exceptional hydrogen evolution rate up to 3650 μmol h<SUP>−1</SUP> g<SUP>−1</SUP> without resorting to any noble-metal co-catalysts under visible-light irradiation owing to synergistic effects envisaged by a rational material design. Our results may provide a useful strategy to develop a highly-efficient visible-light-driven hydrogen production system via water splitting.</P>

Highly efficient hydrogen evolution catalysis based on MoS₂/CdS/TiO₂ porous composites

Du, Jimin,Wang, Huiming,Yang, Mengke,Zhang, Fangfang,Wu, Haoran,Cheng, Xuechun,Yuan, Sijie,Zhang, Bing,Li, Kaidi,Wang, Yina,Lee, Hyoyoung Elsevier 2018 International journal of hydrogen energy Vol.43 No.19

<P><B>Abstract</B></P> <P>Efficient production of hydrogen through visible-light-driven water splitting mechanism using semiconductor-based composites has been identified as a promising strategy for converting light into clean H<SUB>2</SUB> fuel. However, researchers are facing lots of challenges such as light absorption and electron-hole pair recombination and so on. Here, new sheet-shaped MoS<SUB>2</SUB> and pyramid-shaped CdS <I>in-situ</I> co-grown on porous TiO<SUB>2</SUB> photocatalysts (MoS<SUB>2</SUB> CdSTiO<SUB>2</SUB>) are successfully obtained <I>via</I> mild sulfuration of MoO<SUB>3</SUB> and CdO coexisted inside porous TiO<SUB>2</SUB> monolith by a hydrothermal route. The scanning electron microscopy and transmission electron microscopy results exhibit that the MoS<SUB>2</SUB> CdSTiO<SUB>2</SUB> composites have average pore size about 500 nm. The 3%MoS<SUB>2</SUB> 10%CdSTiO<SUB>2</SUB> demonstrated excellent photocatalytic activity and high stability for a hydrogen production with a high H<SUB>2</SUB>-generation rate of 4146 μmol h<SUP>−1</SUP> g<SUP>−1</SUP> under visible light irradiation even without noble-metal co-catalysts. The super photocatalytic performance of the visible-light-driven hydrogen evolution is predominantly attributed to the synergistic effect. The conduction band of MoS<SUB>2</SUB> facilitates in transporting excited electrons from visible-light on CdS to the porous TiO<SUB>2</SUB> for catalytic hydrogen production, and holes to MoS<SUB>2</SUB> for inhibiting the photocorrosion of CdS, respectively, leading to enhancing the efficient separation of electrons and holes.</P> <P><B>Highlights</B></P> <P> <UL> <LI> MoS<SUB>2</SUB>-CT photocatalysts have been successfully synthesized by two-step method. </LI> <LI> The porous structure can enhance photogenerated electron-hole pairs separation. </LI> <LI> The 3% MoS<SUB>2</SUB>-CT shows an excellent H<SUB>2</SUB> evolution rate of 4146 μmol h<SUP>−1</SUP> g<SUP>−1</SUP>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Characteristics of the Infection of Tilletia laevis Kühn (syn. Tilletia foetida (Wallr.) Liro.) in Compatible Wheat

Zhaoyu Ren,Wei Zhang,Mengke Wang,Haifeng Gao,Huimin Shen,Chunping Wang,Taiguo Liu,Wanquan Chen,Li Gao 한국식물병리학회 2021 Plant Pathology Journal Vol.37 No.5

Tilletia laevis Kühn (syn. Tilletia foetida (Wallr.) Liro.) causes wheat common bunt, which is one of the most devastating plant diseases in the world. Common bunt can result in a reduction of 80% or even a total loss of wheat production. In this study, the characteristics of T. laevis infection in compatible wheat plants were defined based on the combination of scanning electron mi- croscopy, transmission electron microscopy and laser scanning confocal microscopy. We found T. laevis could lead to the abnormal growth of wheat tissues and cells, such as leakage of chloroplasts, deformities, disordered arrangements of mesophyll cells and also thickening of the cell wall of mesophyll cells in leaf tissue. What’s more, T. laevis teliospores were found in the roots, stems, flag leaves, and glumes of infected wheat plants instead of just in the ovaries, as previously reported. The abnormal characteristics caused by T. laevis may be used for early detection of this pathogen instead of molecular markers in addition to providing theoretical insights into T. laevis and wheat interactions for breed- ing of common bunt resistance.

A stable and highly efficient visible-light-driven hydrogen evolution porous CdS/WO₃/TiO₂ photocatalysts

Qian, Yongteng,Yang, Mengke,Zhang, Fangfang,Du, Jimin,Li, Kaidi,Lin, Xialing,Zhu, Xinrui,Lu, Yayun,Wang, Weimin,Kang, Dae Joon Elsevier 2018 Materials characterization Vol.142 No.-

<P><B>Abstract</B></P> <P>It is well known that both catalytic efficiency and stability are the two important parameters of photocatalysts for visible-light-driven hydrogen production reactions. However, light-driven hydrogen evolution based applications still suffer from sluggish reaction kinetics due to the lack of high-performance photocatalysts. In this paper, we successfully synthesized a ternary porous CdS/WO<SUB>3</SUB>/TiO<SUB>2</SUB> photocatalyst with high efficiency and stability via two-stage approach. The as-prepared samples are characterized by XRD, FESEM, EDS, TEM, XPS, and UV–Vis, respectively, which illustrated that the CdS and WO<SUB>3</SUB> moieties are in-situ formed inside the porous TiO<SUB>2</SUB>. Particularly, the photocatalytic hydrogen (H<SUB>2</SUB>) evolution rate of such ternary 8% CdS/WO<SUB>3</SUB>/TiO<SUB>2</SUB> (molar ration of CdS:WO<SUB>3</SUB>:TiO<SUB>2</SUB> = 8:8:100) photocatalyst ranges up to 2106 μmol h<SUP>−1</SUP> g<SUP>−1</SUP> under visible-light irradiation, which is higher than that of pure TiO<SUB>2</SUB> and other binary (CdS/TiO<SUB>2</SUB> and WO<SUB>3</SUB>/TiO<SUB>2</SUB>) porous photocatalysts. The superior H<SUB>2</SUB> evolution efficiency can be attributed to the coexistence of CdS and WO<SUB>3</SUB> in porous TiO<SUB>2</SUB> which can promote the interfacial charge transfer and separation as well as extend the light absorption up to the visible range.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Highly efficient and stable photocatalytic activity of CdS/WO<SUB>3</SUB>/TiO<SUB>2</SUB> photocatalysts were synthesized by a two-step method. </LI> <LI> CdS and WO<SUB>3</SUB> inlaid on porous TiO<SUB>2</SUB> can extend the light absorption and enhance photogenerated electron-hole pairs separation. </LI> <LI> The porous structure can provide more reaction active sites and improve photoproduced-electrons and holes transport speed. </LI> </UL> </P> <P><B>Graphical Abstract</B></P> <P>[DISPLAY OMISSION]</P>

Study on the function of Helicoverpa armigera Wnt1 gene using CRISPR/Cas9 system

Fu Xiaozheng,Li Rui,Qiu Qiqi,Wang Mengke,Zhao Te,Zhou Lin 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.1

The Wnt signaling pathway, as a highly conserved signaling pathway in evolution, plays an important role in many biological processes. The research of Wnt signaling pathway through gene editing has been implemented in a variety of organisms. Among the various genome editing tools available for functional genomic research, CRISPR is popular because of its ease of use and versatility. Here, we use the CRISPR/Cas9 system to knock out the HaWnt1 gene of the important agricultural pest Helicoverpa armigera to explore the impacts on embryo development. Direct injection of Cas9 protein and Wnt1-specific single guide RNA (sgRNA) into H. armigera embryos successfully induced Wnt1 gene deletion mutants, which showed high lethality, abnormal segmenta tion, defected appendages and defected pigmentation. qRT-PCR analysis revealed that the deletion of Wnt1 gene affected the expression of several genes, which were closely related to the growth and development of insects. Our results indicate that HaWnt1 signaling pathway is essential for embryonic development of H. armigera. The study of the function of HaWnt1 gene not only lays the foundation for the study of the somatic development pattern of H. armigera, but also provides a candidate gene for genetic control of H. armigera.

Response Surface Methodology for Optimizing the Preparation Process of Cellulose Acetate/Polylactic Acid Nonwoven Surgical Gown Material

Shujie Zhang,Lisong Fu,Zhaowei Yang,Mengke Jing,Ziwei Zhang,Shijian Xiang,Rui Wang 한국섬유공학회 2021 Fibers and polymers Vol.22 No.4

In view of the problems that traditional woven surgical gowns are prone to cross infection in blocking blood andliquid spillage, cellulose acetate (CA)/polylactic acid (PLA) nonwoven materials were prepared to improve the functionalrequirements of surgical materials in combination with the rapidly developing green fibers. Fiber mixing ratio, fiber webareal weight and water jet pressure were selected to optimize the preparation process of cellulose acetate/polylactic acid (CA/PLA) nonwoven materials with moisture permeability and filtration efficiency. The results showed that the fiber mixing ratiowas 49:51, and the fiber web areal weight was 130 g/m2, and the water jet pressure was 7 MPa. Under this process, moisturepermeability is 5240.86 g/(m2·h), and the filtration efficiency is 38.12 %, which is close to the theoretical value. It shows thatthe response surface method has practical application value, indicating that the response surface method has practicalapplication value, and can provide a theoretical basis for the preparation process parameters of barrier and comfort nonwovensurgical gowns at the same time.

Porous NiCo2S4 Networks as Electrodes for Electrochemical Supercapacitors

Jimin Du,Kaidi Li,Yongteng Qian,Mengke Yang,Huiming Wang,Wen He,Viyada Harnchana 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.12

Porous NiCo2S4 networks have been successfully synthesized by a facile one-pot solvothermal method without the use of any surfactant or template. Crystal structure, morphology, composition and surface area of the as-synthesized samples were characterized by X-ray diffraction, field-emission scanning electron microscopy, X-ray photoelectron spectroscopy and Brunauer– Emmet–Teller techniques. Owing to their porous nature and small crystalline size, the as-prepared NiCo2S4 networks based supercapacitor electrodes showed a high specific capacitance of 1250 F · g-1 at 1 A · g-1, and excellent cycling stability with the retention capacity of 70.3% after 5000 cycles in the KOH aqueous solution electrolyte.

Microstructure and solar-blind photo-detection performance of β-Ga₂O₃ thin films prepared by radio-frequency magnetron sputtering with different sputtering powers

Min Zhang,Pai Zhang,Yingnan Zhang,Jingchang Sun,Mengke Li,Yuxin Wang 한국표면공학회 2023 한국표면공학회 학술발표회 초록집 Vol.2023 No.11-1