成果筛选
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筛选条件 : Changming LI
Tiantian Zeng; Xiaomin Meng; Shiwei Sun; Miao Ling; Chuanhui Zhang; Weiyong Yuan
Small Methods, 2023 7 (11) - EI SCIE

摘要 : Noble metal-based metallenes are attracting intensive attention in energy catalysis, but it is still very challenging to precisely control the surface structures of metallenes for higher catalytic properties on account of their intrinsic thermodynamic instability. Herein, the synthesis of tensile-strained holey Pd metallene by oxidative etching is reported using hydrogen peroxide, which exhibits highly enhanced catalytic activity and stability in comparison with normal Pd metallene toward both oxygen reduction reaction and formic acid oxidation. The pre-prepared Pd metallene functions as a catalyst to decompose hydrogen peroxide, and the Pd atoms in amorphous regions of Pd metallene are preferentially removed by the introduced hydrogen peroxide during the etching process. The greatly enhanced ORR activity is mainly determined by the strong electrostatic repulsion between intermediate O and the dopant O, which balances the adsorption strength of O on Pd sites, ultimately endowing a weakened adsorption energy of O on TH-Pd metallene. This work creates a facile and economical strategy to precisely shape metallene-based nanoarchitectures with broad applications for energy systems and sensing devices.

Ke Jiang Li; Juan Li; Fan Shi; Li Peng Gan; Wei Sun; Zhi Song Lu
Electroanalysis (Weinheim. Internet), 2023 35 (10) - SCIE

摘要 : Dopamine (DA) plays an essential role in the central nervous, renal, hormonal and cardiovascular systems. Various modified carbon nanotubes (CNT)-based dopamine sensors have been reported, but inexpensive, highly sensitive plain CNT-based ones are seldom studied. In this work, a facile and inexpensive CNT-based DA sensor is made by rich-defect multi-walled carbon nanotubes (RD-CNT) via an ultrasound method. The defect and elemental states of the RD-CNT are systematically studied by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), Raman spectroscopy, X-ray powder diffraction (XRD) and X-ray-photoelectron spectroscopy (XPS). Results show that massive holes and cracks exist in RD-CNT. The level of defects increases from the additional exposed edges. The electrochemical characterizations indicate that the electrochemical sensor has the highest sensitivity of 438.4 μA/(μM ⋅ cm2) among all carbon materials-based DA sensors while well meeting the clinically required detection range and selectivity. The DA sensor was further used to detect live healthy human serum and live PC12 cells with satisfactory results, thus holding great promise for an inexpensive but sensitive DA sensor in practical applications of clinical diagnosis and biological research.

Qiyi Yang; Lian Ying Zhang; Sainan Ma; Wei Wang; Ming Zhao; Weiyong Yuan
ACS Applied Energy Materials, 2023 6 (18) - EI SCIE

摘要 : Nanoporous cocatalysts can guide the growth of catalysts with promoted activity, but it is extremely challenging to identify, synthesize, and integrate them to fabricate supported nanoelectrocatalysts with high performance. An ultrathin, uniform layer of nanoporous TiO2 has been self-assembled on pristine graphene to mediate Pd growth. Ultrasmall, uniform, and highly dispersed Pd nanoparticles (NPs) have been selectively grown in TiO2 nanopores due to nanopore-enhanced adsorption of PdCl42– and in situ nucleation of Pd seeds. The obtained graphene-supported TiO2-nanopore-confined Pd NPs show remarkably improved formic acid oxidation reaction (FAOR) catalytic performance compared to Pd NPs grown on graphene and on nonporous-TiO2-modified graphene and commercial Pd/C. The activity is among the highest reported for Pd-based catalysts. The superior performance is ascribed to the ultrasmall and highly dispersed Pd NPs embedded in graphene-supported nanoporous TiO2, which create an ultrahigh electrochemically active surface area, and the large interface area between TiO2 and intimately grown Pd NPs, which significantly enhances intrinsic catalytic activity via the bifunctional mechanism. This work not only develops a strategy to fabricate graphene-supported Pd NPs with cocatalysts effectively integrated for achieving excellent catalytic performance but also sheds light on the mechanisms of nanopore-confined growth of Pd NPs and nanopore-enhanced promotion of FAOR catalysis.

Chunmei Li; Sainan Ma; Ming Zhao; Maoxiang Jing; Weiyong Yuan; Changming Li
ACS Sustainable Chemistry & Engineering, 2023 11 (32) - EI SCIE

摘要 : Hematite (α-Fe2O3) core–cocatalyst shell nanoarchitectures with ultrathin hybrid shells are promising to maximize photoelectrochemical (PEC) water oxidation performance of Fe2O3-based photoelectrodes, but their fabrication presents formidable challenges. For the first time, a wormlike nanostructured α-Fe2O3@Co3O4/graphene quantum dot (GQD) core–hybrid shell nanoarray is synthesized via self-assembly, showing an onset potential of 0.63 V (vs the reversible hydrogen electrode (RHE)) and a photocurrent density of 3.63 mA cm–2 at 1.23 V (vs RHE). This performance is superior to those of reported Fe2O3-based heterojunction photoanodes and among the best reported for Fe2O3-based photoanodes. The outstanding performance is due to the Co3O4/GQD shell significantly promoting charge separation and transfer and hole injection as well as great synergistic effects between GQDs and Co3O4. This work not only fabricates a low-cost photoanode with record-high water oxidation performance and offers scientific insights into the enhancement mechanism but also provides a facile, economical, and universal strategy to self-assemble conformal, ultrathin hybrid shells on three-dimensional (3-D) complex nanostructures, which have broad applications in the fields of energy, environment, and sensing.

Shuchan Wang; Wenwen Deng; Zhiyuan Geng; Peiyuan Li; Naiqi Hu; Limin Zhu
Battery Energy, 2023 2 (2)

摘要 : Applications of organic compounds-based electrodes in aqueous zinc-ion batteries (AZIBs) at low temperatures are severely restricted by the freezing of aqueous electrolytes and the inferior dynamic behavior of organic electrodes below zero. Herein, tetracyanoquinodimethane (TCNQ) was purified by the sublimation method and used as a cathode in AZIBs to investigate electrochemical Zn storage performance in comparison with nonpurified TCNQ at a temperature range of 25°C to −40°C. Nuclear magnetic resonance and elemental analysis prove increased purity in purified TCNQ (p-TCNQ), whereas scanning electron microscope and Brunner−Emmet−Teller data verify reduced particle size and increased surface area of p-TCNQ. Kinetic analysis demonstrates that p-TCNQ is a more surface-controlled electrode process than TCNQ and offers much higher ionic diffusivity than the latter at various temperatures. Molecular dynamics simulation validates that the existence of impurity increases the absorption energy of TCNQ in a TCNQ//Zn system that is unfavorable to Zn migration. Comprehensive analysis, including ex situ X-ray diffraction, Fourier transform infrared, Raman, and electron spin-resonance spectroscopy characterization confirm the high reversibility of transformation between C≡N and −C═N groups in p-TCNQ. This work provides a simple, environmentally friendly strategy to fabricate a high-performance AZIB at low temperatures while offering fundamental chemistry insight into organic electrode performance, thus possessing universal significance.

Yixiang Pan; Xiaoyan Wang; Hua Lin; Qinghua Xia; Maoxiang Jing; Weiyong Yuan
Nanoscale, 2023 15 (34) - EI SCIE

摘要 : Earth abundant transition metal oxide (EATMO)-based bifunctional catalysts for overall water splitting are highly desirable, but their performance is far from satisfactory due to low intrinsic activities of EATMOs toward electrocatalysis of both oxygen and hydrogen evolution reactions and poor electron transfer and transport capabilities. A three-dimensional (3-D) Ni-foam-supported NiCoO2@Co3O4 nanowire-on-nanosheet heterostructured array with rich oxygen vacancies has been synthesized, showing OER activity superior to most reported catalysts and even much higher than Ru and Ir-based ones and HER activity among the highest reported for non-noble-metal-based catalysts. The excellent activities are ascribed to the highly dense, ultrathin nanowire arrays epitaxially grown on an interconnected layered nanosheet array greatly facilitating electron transfer and providing numerous electrochemically accessible active sites and the high content of oxygen vacancies on nanowires greatly promoting OER and HER. When adopted as bifunctional electrodes for overall water splitting, this heterostructure shows an overvoltage (at 10 mA cm−2) lower than most reported electrolyzers and high stability. This work not only creates a 3-D EATMO-based integrated heterostructure as a low-cost, highly efficient bifunctional catalytic electrode for water splitting, but also provides a novel strategy to use unique heteronanostructures with rich surface defects for synergistically enhancing electrocatalytic activities.

Yali Jiang; Jie Chen; Qingxin Zeng; Zhuo Zou; Juan Li; Lingzhi Zeng
Journal of Colloid and Interface Science, 2022 612 - EI SCIE

摘要 : Sub-1 nm pores can lead to an anomalous increase in the supercapacitive performance [1], but it still faces great challenges from its relatively low sub-1 nm pore content, complicated preparation process, low yield and high cost. Here we successfully prepared a sub-1 nm pore-rich carbon from biomass wastes using a facile method by pre-treating walnut shell powder at 380 °C in air for different times to delicately tailor carbon defects, followed by KOH activation at 700 °C. The as-prepared optimal material delivers the highest sub-1 nm pore content (V sub-1 nm = 0.57 cm 3 g −1, V sub-1 nm /V t = 58.4 %) among all reported porous carbons. A supercapacitor made from the material accomplishes an ultrahigh specific capacitance of 298.7F g −1 at 1 A g −1 in a two-electrode device, excellent rate capability (78.8 % retention from 1 to 10 A g −1 ) and long-cyclic life (94 % retention after 10, 000 cycles at 10 A g −1 ) in KOH. Even in Et 4 NBF 4 electrolyte that is often used in commercial supercapacitors, a high energy density of 82.8 Wh kg −1 at 7 kW kg −1 and excellent cycling performance (90 % retention after 10, 000 cycles at 5 A g −1 ) can be achieved, ranking the best among all reported carbon-based electrical double layer capacitors tested in the same electrolyte. More importantly, it drives a light-emitting-diode (LED) to operate for as long as 20 min, vividly demonstrating the great potential of sub-1 nm pore-rich carbon-based high performance supercapacitors in practical applications.

Jiaqi Jin; Jundie Hu; Jiafu Qu; Guangming Cao; Yan Lei; Zhi Zheng
ACS Applied Materials & Interfaces, 2022 14 (15) - EI SCIE

摘要 : The CO2 reduction reaction (CO2RR) is an essential step in natural photosynthesis and artificial photosynthesis to provide carbohydrate foods and hydrocarbon energy in the carbon-neutral cycle. However, the current solar conversion efficiencies and/or product selectivity of the CO2RR are very sluggish due to its complicated multiple-step charge transfer reactions. Here, we systematically investigate the charge transfer reaction rate during CO2 reduction on CuBi2O4 photocathodes, where the surface is modified with 3-aminopropyltriethoxysilane (APTES). We discover that the surface amine group increases the charge separation rate, significantly enhancing the surface charge transfer reaction rate. However, the surface acidity has less influence on the first-order reaction, indicating that a rate-determining step (RDS) exists in the early stage of the photoelectrochemical cell (PEC) processes. Moreover, the intensity-modulated photocurrent spectroscopy (IMPS) confirms that both surface charge transfer and the recombination rate on APTES-coated CuBi2O4 are larger than bare CuBi2O4 while possessing comparable charge transfer efficiencies. Overall, the surface charge transfer reactions under the PEC condition require designing more effective nanostructured photoelectrodes and powerful characterization methods to intrinsically increase the charge separation and transfer rate while reducing the recombination rate.

Lian Ying Zhang; Chun Xian Guo; Haijie Cao; Shuo Wang; Yirui Ouyang; Binghui Xu
Chemical Engineering Journal, 2022 431 - EI SCIE

摘要 : Although great efforts have been devoted to developing Pd-based catalysts to take the place of Pt toward Oxygen reduction reaction (ORR) in acidic medium, the progress is notably slower than expected. In this work, highly wrinkled ultrathin Pd nanosheets are synthesized and further demonstrated as an advanced catalyst for ORR, holding higher catalytic activity, 26 mV more positive half-wave potential and better stability than the commercial Pt/C. Theoretical studies reveal that the compressive strain created from the wrinkles can crucially downshift d-band center of Pd to reduce the reaction barrier of the rate determining steps of ORR for fast kinetics. The modulated electronic structure of Pd by the introduction of wrinkles display a major role in improving the stability. This work offers a non-Pt, highly active, and stable catalyst for ORR by tailoring the geometric structure of Pd, while shedding a scientific light on the enhancement mechanism of a nanostructure on electrocatalytic activity and stability.

Xiaoyan Wang; Jia Bo Le; Yang Fei; Ruiqin Gao; Maoxiang Jing; Weiyong Yuan
Journal of Materials Chemistry A: Materials for energy and sustainability, 2022 10 (14) - EI SCIE

摘要 : In situ mixing of transition metal phosphides (TMPs), especially those with dissimilar metals, in ultrasmall spaces and assembling them on nanoscale supports for remarkably enhanced hydrogen evolution reaction (HER) activity are rather challenging. We have fabricated pristine graphenesupported ultrasmall, highly dispersed, and high-density Co–W–P nanoparticles (NPs) via phosphotungstic acid-mediated self-assembly. This nanohybrid exhibits outstanding activity with all of the onset overpotential, overpotential (10 mA cm−2), Tafel slope, and exchange current density in both 0.5 M H2SO4 and 1 M KOH superior to those of most reported non-noble-metal-based catalysts and excellent durability showing negligible current change after 24 h chronoamperometric measurement and after 2000 CV cycles. The superior catalytic performance is ascribed to in situ intimately grown Co–W–P NPs with ultrasmall sizes and high dispersion greatly promoting electron transfer, ultrasmall and well-dispersed Co–W–P NPs on graphene providing numerous electrochemically accessible active sites, and synergistic interaction between WP2 and CoP significantly enhancing intrinsic activity. This work not only develops a facile and economical strategy to synthesize pristine graphene supported mixed phosphides of dissimilar transition metals as low-cost and high-performance HER electrocatalysts, but sheds light on synergistic effects between TMPs for high activity and self-assembly mechanisms toward the synthesis of various unique nanohybrids.