查找使用阿拉丁产品的科研文献

3D/2D ZnIn2S4/BiFeO3 as S-scheme heterojunction photocatalyst for boosted visible-light hydrogen evolution

Dafeng Zhang,Ruiqi Zhang,Junchang Liu,Xipeng Pu,Peiqing Cai

Photocatalytic H 2 evolution technique has been proved to be one of the promising approaches to overcome the present energy and environmental issues caused by the combustion of fossil fuel. Constructing heterojunction can realize the efficient separation and migration of charges and thus achieve enhanced H 2 evolution performance. Herein, we designed and prepared a ZnIn 2 S 4 /BiFeO 3 heterojunction photocatalyst with a 3D/2D structure via an ultrasonic self-assembly process. The typical 3D/2D structure with intimate interface was obtained, which not only provided more active sites but also boosted the migration of photogenerated charges. The optimal mass ratio of BiFeO 3 in ZnIn 2 S 4 /BiFeO 3 was determined to be 10%, and a 10.5-fold increase in H 2 evolution rate in comparison with of pure ZnIn 2 S 4 was achieved. Furthermore, the ZnIn 2 S 4 /BiFeO 3 composite exhibited excellent recyclability and structural stability based on cycling experiment. A S-scheme heterojunction mechanism was revealed according to the experimental results of photocatalytic H 2 evolution and electrochemical tests.

Poly(ethylene glycol)s With a Single Cinnamaldehyde Acetal Unit for Fabricating Acid-Degradable Hydrogel

Zhao Xinyue,Shan Pengfei,Liu Haiwei,Li Daai,Cai Peihan,Li Zhongyu,Li Zhihui

A synthetic route to prepare a poly(ethylene glycol) with a single cinnamaldehyde acetal unit in the polymer chain, was successfully established using a newly synthesized cinnamaldehyde acetal diethylene glycol (CADEG) as initiator. This HO-PEG(ca)-OH is non-toxic and would be degraded into a cinnamaldehyde and two PEG diols in acid environment. A whole polyethylene glycol based hydrogel was easily fabricated by thiol-ene “click” reaction in alkalescence aqueous solution using acrylate-PEG(ca)-acrylate and 4-arm PEG-SH as raw materials at room temperature. The gel time was dependent on the pH of the solution and its alkalinity can promote gel. The hydrogel can be degradable in acidic conditions and the stronger the acidity, the faster the degradation. This HO-PEG(ca)-OH also can be used in synthesis of cinnamaldehyde containing PEG derivatives, block copolymers or other acid degradable materials.

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.

Synthesis, structures, and electrochromic behaviors of poly(triarylamine)s based on 3-substituted thiophene derivatives

Jinrui Lin,Xiuyuan Ni

Two triarylamine-based polymers were synthesized by oxidative coupling reactions from 3-(N,N-diphenylamino) thiophene (3PAT) and 3-(10H-phenothiazin-10-yl) thiophene (3PTT) monomers, respectively. Distinguished from 3PAT, 3PTT has an additional sulfur atom between the two benzene rings. By using NMR spectroscopy and triarylamine control, the structures of the synthesized polymers were resolved with the aim of revealing the substitution effect. The results present that the substituent plays an important role in the chain propagation. Moreover, the triarylamine-based polymers were investigated for their solubility, thermal stability and electrochemical properties. To evaluate the electrochromism of the two different polymers, we have measured the spectroelectrochemical and electrochromic switching properties from the solution-cast films.

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

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.

Structure and dynamics heterogeneity in poly(vinyl acetal)s: The effect of side group length

Chunlei Xu,Hang Guo,Changzhu Lv,Wei Chen,Liangbin Li,Kunpeng Cui

Understanding on the structure and dynamics of poly(vinyl acetal)s is insufficient due to the complicated chemical structure and amorphous nature of this type of polymers. In this work, we investigate the effect of side group length on structure and dynamics heterogeneity at different length scales spanning from side group, segment, and polymer network by combing dynamic mechanical analysis (DMA), dielectric relaxation spectroscopy (DRS), solid-state NMR, and differential scanning calorimetry analysis (DSC). By increasing the length of acetal side group, its intrinsic dynamics slows down. Taking into account the scale of segment and networks, with the increase of acetal group length, the formation of cross-linking sites formed by the hydroxyl-rich domain is suppressed, the relaxation distribution of the segment widens, and the volume fraction of rigid component decreases. The effect of side group length on the structure and dynamics heterogeneity of poly(vinyl acetal)s at different scales results in significant changes in material properties such as the non-monotonic change in loss factor value (tan δ ) and a monotonous reduction in glass transition temperature ( T g ).

ZDHHC3-mediated SCAP S-acylation promotes cholesterol biosynthesis and tumor immune escape in hepatocellular carcinoma

Mingzhi Wu,Xiaojun Zhou,Xinyi Zhou,Genxin Wang,Yiqun Zeng,Jun Li,Edward V. Prochownik,Fubing Wang,Youjun Li

Cholesterol metabolism reprogramming plays essential roles in hepatocellular carcinoma (HCC). However, precisely how cholesterol metabolism is dysregulated is not clear. Here, we show that the palmitoyltransferase ZDHHC3 and depalmitoylase ABHD17A regulate HCC cell cholesterol biosynthesis by dynamically S-acylating SREBP cleavage-activating protein (SCAP). SCAP S-acylation by ZDHHC3 at C264 antagonizes HACE1-mediated SCAP ubiquitination. Intriguingly, SREBP2 transcriptionally upregulates ZDHHC3 to form a positive feedback loop, which explains why negative feedback regulation of SCAP/SREBP2 signaling fails in HCC. Increased cholesterol in the tumor microenvironment (TME) restrains CD4 + T cell cytotoxicity. Hence, the cholesterol metabolism reprogramming and cholesterol level alternation in the TME cooperate to promote HCC development. We identified a small-molecule inhibitor of ZDHHC3 that, combined with anti-PD-1 immunotherapy, inhibited diethyl nitrosamine (DEN)/CCl 4 -induced HCC growth in mice. ZDHHC3-mediated SCAP S-acylation reprograms cholesterol metabolism and promotes HCC immune escape. ZDHHC3 is thus identified as a rational chemotherapy target for HCC.

Zinc-doped C4N3/BiOBr S-scheme heterostructured hollow spheres for efficient photocatalytic degradation of tetracycline

Yaqi Liu,Guicheng Luo,Yichen Liu,Zuozheng Xu,Hengxin Shen,Yuxiang Sheng,Yuan Zhu,Shuyi Wu,Lizhe Liu,Yun Shan

Photocatalytic degradation of organic pollutants in water is of great significance to the sustainable development of the environment, but encounters limited efficiency when a single compound is used. Thus, there have been enormous efforts to find novel photocatalytic heterostructured composites with high performance. In this work, a novel S-scheme heterostructure is constructed with BiOBr and Zn2+ doped C4N3 (Zn–C4N3) by a solvothermal method for efficient photodegradation of tetracycline (TC), a residual antibiotic difficult to be removed from the aquatic environment. Thanks to Zn2+-doping induced improvement in chemical affinity between Zn–C4N3 and BiOBr, well-formed Zn–C4N3/BiOBr heterostructured hollow spheres are formed. This structure can efficiently suppress fast recombination of photogenerated electron–hole pairs to enhance the photocatalytic activity of BiOBr dramatically. At a room temperature of 25 °C and neutral pH 7, the catalyst can degrade a significant portion of TC pollutants within 30 min under visible light. Also, the Zn–C4N3/BiOBr heterostructure displays good stability after recycling experiments. Free radical capture experiments and ESR tests show that ˙O2− is the main active substance for photocatalytic degradation of TC. This study provides new insights for constructing heterostructures with an intimate interface between the two phases for photocatalytic applications.

Facilitating extensive CC bond cleavage in lignin models through customized CeO2/C3N4 S-scheme heterojunction

Hongwu Liao,Chong Wang,Jiaxian Zheng,Zhuo Chen,Yulin Zhou,Chengning Ye,Xiangfeng Lin,Meng An,Yusuke Yamauchi,Yusuke Asakura,Zhanhui Yuan

Photocatalytic depolymerization of lignin offers a sustainable approach to producing high-value-added aromatic compounds. Recently, carbon nitride has demonstrated notable selectivity for the C C bonds in lignin model compounds. However, limitations of pure carbon nitride include the low mobility of photogenerated electrons and the difficulty in precisely controlling the cleavage pathways and products of C C bonds. In this study, we constructed an S-Scheme heterojunction by in situ loading of Ce ions onto C 3 N 4 to form a CeO 2 /C 3 N 4 composite. This heterojunction achieves efficient lignin depolymerization under blue LED irradiation in an oxygen-rich environment. Comparative analysis indicated that the yield of primary products, benzaldehyde and phenyl formate, increased by 7.8-fold and 7.75-fold, respectively, compared with pure CeO 2 , and by 1.4 and 1.8 times relative to unmodified C 3 N 4 . After optimizing the reaction conditions, dealkalized lignin is applied to the system and successfully depolymerized. Comprehensive characterization and theoretical simulations verify the heterojunction's ability to enhance carrier separation and redox activity, with CeO 2 serving as an active dehydrogenation site that significantly boosts the depolymerization efficiency of lignin model compounds. This photocatalytic strategy presents a valuable step forward in lignin valorization and supports the sustainable utilization of biomass resources.

Photothermal-Enhanced S-Scheme Heterojunction of Hollow Core–Shell FeNi2S4@ZnIn2S4 toward Photocatalytic Hydrogen Evolution

Shikai Wang,Dong Zhang,Xipeng Pu,Lizhi Zhang,Dafeng Zhang,Jizhou Jiang

Herein, guided by the results of density functional theory prediction, the study rationally designs a hollow core–shell FeNi 2 S 4 @ZnIn 2 S 4 (FNS@ZIS) Step-scheme (S-scheme) heterojunction for photocatalytic H 2 evolution with photothermal-assisted. The hollow FNS spheres offered substrate for coating the ZIS nanosheets, which can inhibit ZIS nanosheets from agglomerating into pellet, enrich the active site, increase specific surfaces, and raise the light absorption. Notably, due to its excellent photothermal properties, FNS core generated heat unceasingly inside under visible-light irradiation and effectively prevent the heat loss of the reaction system, which increased the local temperature of photocatalysts and thus accelerated the charge migration. In addition, the S-scheme heterojunction construction via in situ growth has a tight interface, which can facilitate the separation and transfer of carriers and achieve high redox potential. Owning to the distinctive construction, the hollow core–shell FNS@ZIS S-scheme heterojunction show extraordinary stability and photocatalytic H 2 evolution rate with 7.7 mmol h −1 g −1 , which is ≈15.2-fold than pristine ZIS. Based on the double evidence of theoretical predictions and experimental confirmations, the photothermal effect and electron transfer mechanism of this innovative material are investigated in depth by the following infrared thermography technology and deep DFT calculations.

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.