查找使用阿拉丁产品的科研文献

A scalable formation of nano-SnO2 anode derived from tin metal–organic frameworks for lithium-ion battery

Zixu Sun,Can Cao,Wei-Qiang Han

In this work, for the first time, we synthesize a SnO2 nanomaterial through the calcination of tin metal–organic framework (MOF) precursors. X-ray diffraction, field emission scanning electron microscope, transmission electron microscopy, and the Brunauer–Emmett–Teller specific surface area are used to characterize the phases and to observe surface morphologies. This anode material exhibits good electrochemical performance in LIBs with high reversible capacity and cycling stability. The good electrochemical properties could be ascribed to the short transport/diffusion path of electrons and lithium ions and the high contact area between the electrode and electrolyte that results from the nanostructured SnO2. This is low-cost, facile and scalable for mass production of SnO2 nanocomposites as a potential anode material for the next-generation LIBs.

SnO2 hollow nanospheres assembled by single layer nanocrystals as anode material for high performance Li ion batteries

Wei Wei,Ling-Xiao Song,Lin Guo

SnO 2 hollow nanospheres were successfully synthesized via a facile one-step solvothermal method. Characterizations show that the as-prepared SnO 2 spheres are of hollow structure with a diameter at around 50   nm, and especially, the shell of the spheres is assembled by single layer SnO 2 nanocrystals. The surface area of the material reaches up to 202.5   m 2 /g. As an anode material for Li ion batteries, the sample exhibited improved electrochemical performance compared with commercial SnO 2 particles. After cycled at high current rate of 0.5   C, 1   C and 0.5   C for 20 cycles, respectively, the electrode can maintain a capacity of 509   mAh/g. The suitable shell thickness/diameter ratio endows the good structural stability of the material during cycling, which promises the excellent cycling performance of the electrode. The large surface area and the ultra thin shell ensure the high rate performance of the material.

Large scale synthesis of highly crystallized SnO2 quantum dots at room temperature and their high electrochemical performance

Hongtao Cui,Yan Liu,Wanzhong Ren,Minmin Wang,Yunan Zhao

In this work, SnO2 quantum dots with high crystallinity were synthesized on a large scale under mild reaction conditions via an epoxide precipitation route. The SnO intermediate, which was produced in the reactions between epoxide and [Sn(H2O)6]2+, was converted to SnO2 quantum dots by the oxidation of H2O2. It is believed that the protonation and the following ring opening of epoxide promoted the hydrolysis and condensation of [Sn(H2O)6]2+ to form the intermediate. The obtained quantum dots had a maximum specific capacitance of 204.4 F g−1 at a scan rate of 5 mV s−1 in 1 mol l−1 KOH aqueous solution. The electrochemical measurements proved that this high specific capacitance of SnO2 resulted from the Faradaic reactions between SnO2 and the electrolyte. This demonstrates for the first time that SnO2 can be used as a pseudocapacitive electrode material.

Design of less than 1 nm Scale Spaces on SnO2 Nanoparticles for High-Performance Electrochemical CO2 Reduction

Mun Kyoung Kim,Hojeong Lee,Jong Ho Won,Woohyeong Sim,Shin Joon Kang,Hansaem Choi,Monika Sharma,Hyung-Suk Oh,Stefan Ringe,Youngkook Kwon,Hyung Mo Jeong

Electrochemical carbon dioxide reduction reaction (CO 2 RR) is a promising approach to mitigate CO 2 concentration and generate carbon feedstock. Recently, the (sub-)nanometer design of catalyst structures has been revealed as an efficient means to control the reaction process through the local reaction environment. Herein, the synthesis of a novel tin oxide (SnO x ) nanoparticle (NP) catalyst with highly controlled sub-nanoscale interplanar gaps of widths <1 nm (SnO x NP-s) is reported via the lithium electrochemical tuning (LiET) method. Transmission electron microscopy (TEM) and 3D-tomo-scanning TEM (STEM) analysis confirm the presence of a distinct segmentation pattern and the newly engineered interparticle confined space in the SnO x NP-s. The catalyst exhibits a significant increase in CO 2 RR versus hydrogen evolution selectivity by a factor of ≈5 with 20% higher formate selectivity relative to pristine SnO 2 NPs at −1.2 V RHE . Density functional theory calculations and cation-size-dependent experiments indicate that this is attributable to a gap-stabilization of the rate-limiting *OCHO and *COOH intermediates, the formation of which is driven by the interfacial electric field. Moreover, the SnO x NP-s exhibits stable performance during CO 2 RR over 50 h. These results highlight the potential of controlled atomic spaces in directing electrochemical reaction selectivity and the design of highly optimized catalytic materials.

Metal modified (Ni, Ce, Ta) Ti/SnO2–Sb2O5–RuO2 electrodes for enhanced electrochemical degradation of Orange G

Zhao Ruiyu,Wang Yi Mou,Li Jie,Meng Wenhua,Yang Chunli,Sun Chongxiang,Lan Xuefang

Ni, Ce, and Ta modified Ti/SnO 2 –Sb 2 O 5 –RuO 2 anodes were first prepared by thermal decomposition strategy and applied for Orange G degradation to explore the effect of Ni, Ce, and Ta modification on electrocatalytic property. The Ta modified anode showed the highest ·OH generation capability and the lowest charge transfer resistance among all samples, conducive to electrocatalytic degradation of Orange G. Besides, the Ta modified anode shows more cracks than Ni and Ce modified anodes, which is expected to create more specific surface areas and more exposed active sites for Orange G degradation. The degradation efficiency and the total organic carbon (TOC) removal rate increased in the order Ru < Ru–Ni < Ru–Ce < Ru–Ta, with Ru–Ta showing the highest degradation efficiency of 98.6% and 44.2%, much higher than 79.6% and 27.5% of Ru, respectively. Graphical abstract

High-Performance Room-Temperature NO2 Gas Sensor Based on Au-Loaded SnO2 Nanowires under UV Light Activation

Bo Zhang,Shuai Zhang,Yi Xia,Pingping Yu,Yin Xu,Yue Dong,Qufu Wei,Jing Wang

Optical excitation is widely acknowledged as one of the most effective means of balancing sensor responses and response/recovery properties at room temperature (RT, 25 °C). Moreover, noble metals have been proven to be suitable as photosensitizers for optical excitation. Localized surface plasmon resonance (LSPR) determines the liberalization of quasi-free electrons in noble metals under light irradiation, and numerous injected electrons in semiconductors will greatly promote the generation of chemisorbed oxygen, thus elevating the sensor response. In this study, pure SnO2and Au/SnO2nanowires (NWs) were successfully synthesized through the electrospinning method and validated using XRD, EDS, HRTEM, and XPS. Although a Schottky barrier led to a much higher initial resistance of the Au/SnO2composite compared with pure SnO2at RT in the dark, the photoinduced resistance of the Au/SnO2composite became lower than that of pure SnO2under UV irradiation with the same intensity, which confirmed the effect of LSPR. Furthermore, when used as sensing materials, a detailed comparison between the sensing properties of pure SnO2and Au/SnO2composite toward NO2in the dark and under UV irradiation highlighted the crucial role of the LSPR effects. In particular, the response of Au/SnO2NWs toward 5 ppm NO2could reach 65 at RT under UV irradiation, and the response/recovery time was only 82/42 s, which far exceeded those under Au modification-only or optical excitation-only. Finally, the gas-sensing mechanism corresponding to the change in sensor performance in each case was systematically proposed.Keywords:Au-loaded;UV irradiation;synergistic effect;NO2;gas sensor

Reduced Eloss of Planar-Structured Carbon Counter Electrode-Based CsPbI3 Solar Cells with Tetrabutylammonium Halide-Modified SnO2

Wenbo Li,Duoling Cao,Xiaorui Zhu,Zhiguang Guo,Li Wan,Xu Zhang,Xiuhua Zhang,Yuebin Li,Xiaoming Ren,Xianbao Wang,Dominik Eder,Shimin Wang

Cesium lead triiodide (CsPbI3) perovskite with excellent thermal stability owing to its inorganic components has an appropriate band gap and requires no mixed halides for an application in Si tandem solar cells. However, CsPbI3 solar cells have poorer power conversion efficiency (PCE) than organic–inorganic hybrid perovskite solar cells (PSCs) with the same band gap. Tuning electron transport layers (ETL) is an effective method to promote PCE and suppress its hysteresis in PSCs. In this study, the tin dioxide (SnO2) surface was modified with tetrabutylammonium chloride (TBAC), tetrabutylammonium bromide, or tetrabutylammonium iodide. The tetrabutylammonium halogen interlayers increase the conductivity of the SnO2-ETL while lowering the work function, thus making the electron transport more efficient. Moreover, these interlayers alter the SnO2 surface roughness, facilitating high-quality CsPbI3 films with bigger grain sizes and fewer grain boundaries and hence reduced Eloss for PSCs with improved PCE. The optimized carbon counter electrode (CE)-based hole transport layer-free device of fluoride-doped tin oxide/SnO2/TBAC/CsPbI3/C achieves the relatively highest PCE of 12.85%, which is larger than that of pristine PSCs (10.51%) and is also one of the highest efficiencies reported to date for planar-structured CsPbI3 PSCs based on a carbon CE. Our work demonstrates a facile approach of simultaneously optimizing the SnO2-ETL and CsPbI3 film for the construction of efficient carbon CE-based CsPbI3 solar cells.

SnO2 nanoparticles uniformly encapsulated in polyaniline-derived nitrogen-doped carbon as anode materials for lithium-ion batteries

Shuqing Nie,Qiuyun Wang,Chang Miao,Shuxin Chen,Yu Xin,Wei Xiao

SnO 2 nanoparticles encapsulated in polyaniline (PANI)-derived nitrogen-doped carbon composite powders (SnO 2 /NC) are successfully synthesized by in-situ polymerization and carbonization processes under an inert atmosphere . The results indicate that SnO 2 nanoparticles of the targeted powders (SnO 2 /NC-3) are uniformly dispersed in the N-doped carbon matrix when the added amount of SnCl 4 ·5H 2 O is precisely controlled at 3 mmol, in which PANI suppresses the aggregation of SnO 2 nanoparticles and is converted into N-doped carbon during the calcination process. The cell assembled with the SnO 2 /NC-3 electrode displays high initial discharge specific capacity of 1116.3 mAh g −1 and reversible discharge specific capacity of 567.2 mAh g −1 after 100 cycles at 100 mA g −1 . Moreover, the SnO 2 /NC-3 electrode also exhibits relatively high Li + ions diffusion coefficient of about 1.22 × 10 −12  cm 2  s −1 . The improved electrochemical performance can be partly ascribed to the fact that the proper amount of SnO 2 nanoparticles contributes to the enhancement of lithium storage capacity, and partly to that the N-doped carbon effectively relieves the volume expansion of SnO 2 nanoparticles. Therefore, the proposed method of using PANI as N-doped carbon source may provide a feasible strategy to fabricate anode materials for high-performance lithium-ion batteries.

A SnO2 Solution-Gated Transistor Biosensor With High Sensitivity and Low Operating Voltage: Application to Detect Hg2+

Jialing Zhou,Jianwei Zhang,Hui Huang,Ruichen Shang,Senlin Jin,Junwei Cao,Yuan Zhong,Jun Yu,Jing Chen

Effective electron extraction from active layer for enhanced photodetection of photoconductive type detector with structure of Au/CH3NH3PbI3/Au

Han Su,Lina Meng,Yucheng Liu,Yunxia Zhang,Mingxin Hu,Zhou Yang,Shengzhong (Frank) Liu

Increasing the carrier concentration as well as carrier life time could be effective ways to increase the photoresponse of a photoconductive type photodetector . In this paper, layer-structure photodetectors have been fabricated by connecting CH 3 NH 3 PbI 3 film with and without electron transport layer (SnO 2 and SnO 2 /PCBM bilayer). We found that the electron extraction at the electron transport layer and MAPbI 3 interface will boost the photocurrent and responsivity, and faster electron extraction will result in a higher photocurrent improvement. At the same time, the closer is the distance of the interface to the photogenerated electron-hole pairs, the larger is the photocurrent enhancement. The largest photocurrent increasement is almost 3 times the initial value, which increases from 1.54 μA to 6.10 μA.

Development of an Electrochemical Ceramic Membrane Filtration System for Efficient Contaminant Removal from Waters

Junjian Zheng,Zhiwei Wang,Jinxing Ma,Shaoping Xu,Zhichao Wu

Inability to remove low-molecular-weight anthropogenic contaminants is a critical issue in low-pressure membrane filtration processes for water treatment. In this work, a novel electrochemical ceramic membrane filtration (ECMF) system using TiO2@SnO2–Sb anode was developed for removing persistent p-chloroaniline (PCA). Results showed that the ECMF system achieved efficient removal of PCA from contaminated waters. At a charging voltage of 3 V, the PCA removal rate of TiO2@SnO2–Sb ECMF system under flow-through mode was 2.4 times that of flow-by mode. The energy consumption for 50% of PCA removal for TiO2@SnO2–Sb ECMF at 3 V under flow-through mode was 0.38 Wh/L, much lower than that of flow-by operation (1.5 Wh/L), which was attributed to the improved utilization of the surface adsorbed HO· and dissociated HO· driven by the enhanced mass transfer of PCA toward the anode surface. Benefiting from the increased production of reactive oxygen species such as O2•–, H2O2, and HO· arising from excitation of anatase TiO2, TiO2@SnO2–Sb ECMF exhibited a superior electrocatalytic activity to the SnO2–Sb ECMF system. The degradation pathways of PCA initiated by OH· attack were further proposed, with the biodegradable short-chain carboxylic acids (mainly formic, acetic, and oxalic acids) identified as the dominant oxidized products. These results highlight the potential of the ECMF system for cost-effective water purification.

Reducing voltage hysteresis of metal oxide anodes to achieve high energy efficiency for Li-ion batteries

Xuexia Lan,Xingyu Xiong,Jie Cui,Renzong Hu

In the past two decades, a lot of high-capacity conversion-type metal oxides have been intensively studied as alternative anode materials for Li-ion batteries with higher energy density. Unfortunately, their large voltage hysteresis (0.8–1.2 V) within reversed conversion reactions results in huge round-trip inefficiencies and thus lower energy efficiency (50%–75%) in full cells than those with graphite anodes. This remains a long-term open question and has been the most serious drawback toward application of metal oxide anodes. Here we clarify the origins of voltage hysteresis in the typical SnO 2 anode and propose a universal strategy to minimize it. With the established in situ phosphating to generate metal phosphates during reversed conversion reactions in synergy with boosted reaction kinetics by the added P and Mo, the huge voltage hysteresis of 0.9 V in SnO 2 , SnO 2 -Mo, and 0.6 V in SnO 2 -P anodes is minimized to 0.3 V in a ternary SnO 2 -Mo-P (SOMP) composite, along with stable high capacity of 936 mA h g −1 after 800 cycles. The small voltage hysteresis can remain stable even the SOMP anode operated at high current rate of 10 A g −1 and wide-range temperatures from 60 to −30 °C, resulting in a high energy efficiency of 88.5% in full cells. This effective strategy to minimize voltage hysteresis has also been demonstrated in Fe 2 O 3 , Co 3 O 4 -basded conversion-type anodes. This work provides important guidance to advance the high-capacity metal oxide anodes from laboratory to industrialization.