查找使用阿拉丁产品的科研文献

Core–Shell NiS@SrTiO3 Nanorods on Titanium for Enhanced Osseointegration via Programmed Regulation of Bacterial Infection, Angiogenesis, and Osteogenesis

Zheng Liu,Hong Ding,Lin Qi,Jing Wang,Yubao Li,Limin Liu,Ganjun Feng,Li Zhang

Developing bone implants with dynamic self-adjustment of antibacterial, angiogenic, and osteogenic functions in line with a bone regenerative cascade is highly required in orthopedics. Herein, a unique core–shell nanorods array featuring a thin layer of NiS coated on each SrTiO3 nanorod (NiS@SrTiO3) was in situ constructed on titanium (Ti) through a two-step hydrothermal treatment. Under near-infrared (NIR) irradiation, the photoresponsive effect of NiS layer in synergy with the physical perforation of SrTiO3 nanorods initially enabled in vitro antibacterial rates of 96.5% to Escherichia coli and 93.1% to Staphylococcus aureus. With the degradation of the NiS layer, trace amounts of Ni ions were released, which accelerated angiogenesis by upregulating the expression of vascular regeneration-related factors, while the gradual exposure of SrTiO3 nanorods could simultaneously enhance the surface hydrophilicity in favor of cell adhesion and slowly release Sr ions to promote the proliferation and differentiation of MC3T3-E1 cells. The in vivo assessment verified not only the satisfactory antibacterial effect but also the superior osteogenic ability of the NiS@SrTiO3/Ti group with the aid of NIR irradiation, finally promoting the osseointegration of the Ti implant. The modification method endowing Ti implant with antibacterial, angiogenic, and osteogenic functions provides a new strategy to improve the long-term reliability of Ti-based devices.

Hybridization of SrTiO3 and strontium wolframates with very-high-potential photogenerated carriers for degrading the A-ring of tetracycline

Mingjie Zheng,Zhixing Chen,Yongkun Lun,Bin Liu,Wangjian Zhai,Qinyu He

Degrading the A-ring of tetracycline (TC) requires a photocatalyst with either a very negative conduction band edge (CBE) or a very positive valence band edge (VBE). In this work, a SrTiO 3 -based composite with a Sr/W ratio of 7.5% (CSWT75) was prepared by hybridizing the following components: n-type semiconductor Sr 2 WO 5 with CBE of –2.10 V, n-type semiconductor SrWO 4 with a VBE of 4.42 V, and p-type semiconductor Sr 3 WO 6 with CBE of–1.26 V, resulting in formation of z-scheme and p-n heterojunctions. Over CSWT75, the photodegradation rate of the B, C, and D rings of TC was 100% in 60 min and that of A ring was 98% in 90 min. The reaction rate constant of CSWT75 was found to be 3.4-fold that of the as-prepared pure SrTiO 3 . It is found that a high positive VBE potential like that of SrWO 4 4.42 V is more effective on degrading A-ring than a negative CBE potential −0.81 of SrTiO 3 , but less effective than a negative CBE potential −1.26 V of Sr 3 WO 6 . This study identified two new semiconductors with highly negative CBEs. This work also implys that a z-scheme structured composite hybridizing homeotype-semiconductors with very negative CBE favors in degrading A ring of TC.

Significantly enhanced photoelectrochemical cathodic protection performance of hydrogen treated Cr-doped SrTiO3 by Cr6+ reduction and oxygen vacancy modification

Jiangping Jing,Zhuoyuan Chen,Yuyu Bu,Mengmeng Sun,Wenqiang Zheng,Weibing Li

SrTiO 3 is a promising material for the photoelectrochemical (PEC) cathodic protection technology due to its intrinsic band structure . Its disadvantage of light absorption only in the ultraviolet region can be effectively solved by Cr doping. The Cr dopant usually exists as two states of Cr 3+ and Cr 6+ , among which the latter one usually behaves as the trapping center for the photoinduced electrons and leads to the decrease of the PEC performance. In this paper, a hydrogen treatment process is performed on the Cr-doped SrTiO 3 to reduce the Cr 6+ . It is verified that hydrogen treatment reduces Cr 6+ to Cr 3+ , leading to the increase of the concentration of the charge carriers and the decrease of the charge transfer resistance. And also, hydrogen treatment induces the formation of oxygen vacancy , which leads to the negative shift of conduction band potential and the increase of the concentration of the charge carriers. The effect of the hydrogen treatment temperature is further studied in this work. Higher temperature will promote the reduction degree of Cr 6+ and increase the concentration of oxygen vacancy . However, hydrogen treatment with excessively high temperature will induce too high concentration of oxygen vacancy, which would act as the recombination centers of the photogenerated charge carriers, suppress the mobility conduction and thus lead to the decrease of the PEC performance. Therefore, benefiting from the Cr 6+ reduction and modification with appropriate concentration of oxygen vacancy, the Cr-doped SrTiO 3 with hydrogen treatment at 250 °C shows the optimal PEC cathodic protection performance in NaCl solution.

Sandwich structure strategy for constructing BiFeO3-based film capacitor with high energy storage performance

Shuzhi Zhang,Panpan Lv,Yuxin Cui,Tong Pan,Wentao Yang,Hang Zhan,Jia Wang,Ruihang Li,Cuncheng Li,Luchao Ren,Mingwei Zhang

Lead-free dielectric capacitors have been garnering increasing attention for pulsed power applications owing to their green sustainability. BiFeO 3 (BFO) is widely researched in association with dielectric energy-storage applications, owing to its large saturated polarization and high Curie temperature. However, it suffers from serious leakage problems. In this work, BFO-based thin films with different stacking structures are designed and fabricated by introducing a linear dielectric material, SrTiO 3 (STO). The experimental results and finite-element simulations indicate that the polarization and breakdown strength can be simultaneously optimized by regulating the position of the STO layer. In particular, a recoverable energy density of 70 J/cm 3 and efficiency of 60 % is achieved in sandwiched Bi(Fe 0.93 Mn 0.05 Ti 0.02 )O 3 /SrTiO 3 /Bi(Fe 0.93 Mn 0.05 Ti 0.02 )O 3 (BFMTO/STO/BFMTO) film, owing to the synergistic effect of different dielectrics as well as the blocking effect of the interface. The capacitor exhibits a wide operating temperature window (-100–125 °C) and high frequency stability (1–20 kHz), as well as strong fatigue durability (2 × 10 7 cycles). These results demonstrate that the BFMTO/STO/BFMTO film is a promising ecofriendly material for advanced power-capacitor applications.

Ion selection criteria for effective A/B site co-doping in SrTiO3: achieving comprehensive dielectric performance via synergistic pinning effect

Yuhang Zhang,Yanzhao Zhang,Meiling Yang,Kunpeng Lin,Zhe Zhao,Ning Xie,Guoxiang Zhou,Yang Zhihua,Dechang Jia,Yu Zhou

Microwave dielectric ceramics with a high dielectric constant and low dielectric loss are essential for 5   G/6   G miniaturized communication devices; however, inherent property trade-offs hinder further performance optimization. Although A-site rare-earth or B-site composite ion doping has been employed to address this challenge in perovskites, overall performance remains limited by suboptimal A-site selection and B-site ionic mismatch. Here, we synthesized compositionally varied Sr 1-1.5 x Ce x Ti 0.98 (Zn/Mg 1/3 Nb 2/3 ) 0.02 O 3 materials through selective Ce and Zn/MgNb co-doping to simultaneously overcome sintering and dielectric performance challenges. Incorporation of small-radius A-site Ce provides additional solid-solution space for large-radius B-site Zn/MgNb, effectively promoting a single-phase composition and dense microstructure. Crucially, the valence transition of Ce, combined with its synergistic electron-pinning effect with Zn/MgNb, immobilizes free electrons and significantly suppresses Ti 4+ reduction. This synergistic interaction enhances the quality factor beyond 14,000   GHz, surpassing the Q×f values reported in previous studies. Additionally, the controlled reduction in ionic polarizability, coupled with enhanced octahedral distortion, maintains the dielectric constant above 115 while reducing the temperature coefficient from +1400 ppm/°C to +259 ppm/°C. At a doping level of 0.30, the co-doped material exhibits superior comprehensive properties: ε r = 123.9, Q×f = 14,447   GHz, and τ f = +337 ppm/°C. This study highlights the considerable potential of rational co-doping strategies to enhance material performance.

Defect-Driven TiO2– x /SrTiO3– x Heterostructure with Ferroelectricity Enables Shuttle Suppression and Dendrite-Free Growth

Dongqi Fan,Zicheng Wang,Yuan Tian,Cheng Wang

Abstract The inherent Li dendrite growth, notorious shuttle effect, and severe redox reaction kinetics of lithium polysulfides (LiPSs) impede the feasibility of practical development of lithium–sulfur (Li–S) batteries. Herein, a bi-functional defect-rich TiO2–x/SrTiO3–x nanocube, embedded in a N-doped carbon (NC) freestanding fabric, was prepared and effectively used as a sulfur host and an interlayer between the separator and lithium anode for Li–S full batteries. The spontaneous formation of a built-in electric field (BIEF) between TiO2–x and SrTiO3–x guides self-driven charge rearrangement, resulting in strong directional LiPS migration to boost sulfur redox kinetics and fast, uniform Li+ transfer to avoid Li dendrite growth. Meanwhile, the introduction of oxygen vacancies can induce a ferroelectric phase and provide more active sites for lithium/sulfur storage. The whole 3D framework, enabled with fast electron/ion transport, reduces the Li nucleation overpotential and lowers the energy barrier for LiPS conversion. Consequently, Li||Li cells with the TiO2–x/SrTiO3–x@NC interlayer cycled stably over 600 h at 5 mA cm–2 and 5 mAh cm–2. Furthermore, Li–S full batteries delivered 1285 mAh g–1 at 0.1 C with merely 0.074% per-cycle capacity decay. Our findings emphasized the efficacy of a defect-rich TiO2–x/SrTiO3–x ferroelectric heterostructure implanted into a 3D conductive framework.

Fast charge separation from synergistic effect of plasma Bi metal and BiOCl/SrTiO3 S-scheme heterojunction promotes NO deep removal

Jiaoping Si,Hongjing Liu,Wendong Zhang,Dengyu Jiao,Wangxing Ai,Yuerui Ma,Lihuan Feng,Xing’an Dong,Wenjie He,Peng Chen

The catalytic conversion of nitrogen oxides (NO x ) to non-toxic products has emerged as a critical strategy for air pollution control under stringent emission regulations. Photocatalytic NO x removal performance highly depends on the transmission of photogenerated electrons and the amount of reactive oxygen species (ROS) generated. Herein, the Bi/BiOCl/SrTiO 3 heterostructure photocatalyst was prepared by a simple in situ synthesis method to address the limitations of conventional NOx removal systems. Due to the synergistic effect of bismuth (Bi) surface plasmon resonance (SPR) and the built-in electric field in BiOCl/SrTiO 3 S-scheme heterojunction, Bi/BiOCl/SrTiO 3 showed strong light absorption ability and high charge separation efficiency, with the highest NO removal efficiency reaching 70 %. The enhanced electronic interaction between Bi and BiOCl/SrTiO 3 induced Bi-O covalent bonds with the BiOCl layer to facilitate fast charge separation, promoting the rapid transfer of interfacial photogenerated carriers, this process induces the activation of O 2 and H 2 O to form reactive oxygen species (ROS) to promote the oxidative removal of NO. This study provides new insights into the development of effective photocatalysts with fast charge separation by synergistic metal active sites and built-in electric field of heterojunction for air pollutant purification.

Synergistic charge redistribution at SrTiO3@NH2-MIL-125 S-scheme heterostructure: steering photogenerated reactive species for efficient NO-to-nitrate conversion

Wenrui Dai,Chenxiang Wang,Jiajia Gao,Haotong Ma,Yingchun Miao,Shuo Wang,Zhanshuo Tao,Shuning Xiao

Dual-functional copper (Cu0/Cu2+)-modified SrTiO3-δ nanosheets with enhanced photothermal catalytic performance for CO2 reduction and H2 evolution

Zhuogen Li,Gangqiang Zhu,Weibin Zhang,Lujun Zhu,Baowei Cao,Jianzhi Gao,Xianjin Shi,Yu Huang,Peng Liu,Mirabbos Hojamberdiev

In recent years, metal–semiconductor heterojunctions have been intensively researched in the field of photocatalysis due to the effective spatial separation of photo-induced electron-hole pairs. Here, the dual-functional copper (Cu 0 /Cu 2+ )-modified SrTiO 3-δ nanosheets (Cu/STCO) are successfully synthesized by a two-step route. First, Cu 2+ -doped SrTiO 3-δ (STCO) nanosheets are synthesized by a hydrothermal method and then Cu 0 nanoparticles (NPs) are in situ formed from the STCO under H 2 atmosphere at 500 °C. The optimized ratio 6 %-Cu/STCO photocatalyst exhibits the best photothermal catalytic performance for CO 2 reduction reaction (CO 2 RR) and H 2 evolution performance. The detailed characterization demonstrate that the Cu 2+ dopant extend the light absorption range and the in situ generated Cu 0 NPs effectively improve the separation ability of photogenerated charge carriers by forming the Schottky contact with STCO. The excited localized surface plasmon resonance (LSPR) effect of metallic Cu 0 in Cu/STCO shows a considerable catalysis performance even under 600 nm monochromatic light irradiation. The density functional theory (DFT) calculations suggest that the Cu/STCO diminishes the barrier of the rate-determining steps of the CO 2 RR and H 2 evolution thus perform the outstanding catalysis ability in two filed. This work presents the synergistic effect of Cu 0 and Cu 2+ on enhancing the photothermal catalytic performance for CO 2 RR and H 2 evolution and offers a novel strategy to synthesize the metal–semiconductor nanostructures for efficient harnessing of solar energy into fuel.

Tunable self-powered n-SrTiO3 photodetectors based on varying CuS-ZnS nanocomposite film (p-CuZnS, p-CuS, and n-ZnS)

Yong Zhang,Xiaojie Xu,Xiaosheng Fang

The heterojunction photodetector between n-SrTiO 3 (n-STO) and p-CuS-ZnS (p-CZS) is prepared by a simple chemical bath deposition. The p-CZS/n-STO photodetector exhibits excellent self-powered characteristics under 390-nm light illumination, including high photosensitivity (on/off ratio of 300), fast response speed (0.7/94.6 ms), and good wavelength selectivity (410-380 nm). More importantly, the self-powered n-STO photodetectors can be regulated by varying the composition of CZS film (p-CZS, p-CuS, and n-ZnS). All devices exhibit a large open-circuit voltage and show different self-powered behaviors because of the different built-in electric fields. The open-circuit voltages of the CZS/STO, CuS/STO, and ZnS/STO devices are measured to be 0.56, 0.30, and 0.35 V, respectively. This work provides a simple and effective way to fabricate tunable self-powered photodetectors by varying the composition of the nanocomposite film.

A unique octadecahedron SrTiO3 perovskite oxide with a nano step-shaped facet structure for enhanced photoredox and hydrogen evolution performance

Chuyu Wang,Yan Li,Xiaojiao Cai,Dongping Duan,Qibo Jia

As a typical perovskite-type crystal, strontium titanate (SrTiO3, STO) has remarkable photocatalytic activity and is broadly used in solar-driven overall water splitting. The research on controlling the synthesis of polyhedral STO with different exposures of crystal facets to obtain different optoelectronic properties has been greatly carried out in recent years. However, there are few reports of research on the construction of a nano step-shaped facet structure by the reconstruction of the STO crystal facet at a certain temperature, and the formation mechanism and composition analysis have not been explained clearly. In particular, the influence of crystal surface recombination on the hydrogen production reaction hasn't been thoroughly studied. This work presents the existence of a novel STO with the nano step-shaped facet structure parallel to (100) and (110) facets based on octadecahedron STO by a solid-state reaction, and the formation has been monitored by thermogravimetric analysis and in situ X-ray diffraction. In addition, more importantly, the step-shaped facet structure is rich in Sr, and lacks O and Ti, which is evidenced by EPR and XPS characterization, and it affects the transfer and separation of photo carriers. The complex STO catalysts were prepared by photodeposition of Rh, Cr, and Co to compare the hydrogen production capacity of overall water splitting. The novel step-shaped facet SrTiO3 has a good deposition effect on the cocatalysts, and the synthesized catalyst can effectively shorten the band gap to 1.92 eV and prolong the photogenerated carriers' lifetime to 3.7356 ns. Consequently, the novel SrTiO3 sample deposited co-catalysts achieve remarkable activity with the highest H2 evolution rate of 172.0 μmol h−1, which is 4.6 times higher than that of the original octadecahedron SrTiO3 prepared by the hydrothermal method. The DFT calculation results prove that the excellent photocatalytic performance is due to the lower work function and effective electron transfer of the SrTiO3 (100) crystal facet and Sr-rich (110) crystal facet, which is verified by the obvious electron transfer between the CrO42− and the two kinds of crystal facets.

Anchoring SrTiO3 nanoparticles on layered ZnIn2S4 to construct S-scheme heterojunctions as novel photocatalysts for efficient degradation of MO dye

Xia Xu,Changchun Chen,Lingxiu Shu,Cheng Cheng,Zhonghai Tang,Yifeng Wang,Lin Pan,Zishen Guan

Water pollution can be efficiently treated by semiconductor photocatalysts under sunlight irradiation. In this study, novel S-scheme SrTiO 3 /ZnIn 2 S 4 composites were successfully fabricated via a facile oil-bath method. And the synthesized samples were then characterized by various characterization techniques together with Density Functional Theory (DFT) calculation. The X-Ray Diffraction(XRD)patterns show that SrTiO 3 /ZnIn 2 S 4 composites are composed of cubic perovskite structure SrTiO 3 and hexagonal phase ZnIn 2 S 4 . The High Resolution Transmission Electron Microscope(HRTEM)and Field Emission Scanning Electron Microscope (FESEM) images showed the intimate contacts between SrTiO 3 and ZnIn 2 S 4 are established to form the heterojunction. The photocatalytic activity of the composite was excellent when degrading organic pollutants, which outperformed that of pristine SrTiO 3 and ZnIn 2 S 4 . The prepared SrTiO 3 /ZnIn 2 S 4 -33% composite sample was proved to have the best photocatalytic activity, with 98 % degradation of organic pollutants under 32 min. The ·O 2 – is the main active reaction species for the degradation of organic pollutants, which was demonstrated by free radical trapping experiment. In addition, the mineralization of organic pollutants during the degradation process was analyzed by Total Organic Carbon (TOC) test. According to a series of experimental and theoretical calculations, the S-scheme heterojunction formed in the SrTiO 3 /ZnIn 2 S 4 composite is put forward for comprehending the photocatalytic degradation of organic pollutants and the formation of free radicals.