Publications by authors named "Xingzhu Wang"

Tin dioxide (SnO) stands as a promising material for the electron transport layer (ETL) in perovskite solar cells (PSCs) attributed to its superlative optoelectronic properties. The attainment of superior power conversion efficiency hinges critically on the preparation of high-quality SnO thin films. However, conventional nanoparticle SnO colloids often suffer from inherent issues such as numerous oxygen vacancy defects and film non-uniformity.

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Chemically modifiable small-molecule hole transport materials (HTMs) hold promise for achieving efficient and scalable perovskite solar cells (PSCs). Compared to emerging self-assembled monolayers, small-molecule HTMs are more reliable in terms of large-area deposition and long-term operational stability. However, current small-molecule HTMs in inverted PSCs lack efficient molecular designs that balance both the charge transport capability and interface compatibility, resulting in a long-standing stagnation of power conversion efficiency (PCE) below 24.

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Continuous side reactions between conventional carbonate-based electrolytes and electrodes lead to electrolyte consumption and the growth of lithium dendrites, which always lead to serious capacity fading or safety issues, hindering the development of lithium metal batteries. Here, a nonflammable all-fluorinated electrolyte with the anion-participating Li solvation sheath is developed and the corresponding electrochemical properties are studied. Combining theoretical calculations and X-ray photoelectron spectroscopy analysis, ethyl 2,2,2-trifluoroethyl carbonate (ETFEC) and methyl difluoroacetate (MDFA) as cosolvents in the all-fluorinated electrolyte, PF anions accumulate on the lithium metal anode and preferentially reduced to obtain a LiF-rich solid electrolyte layer, inducing uniform lithium metal deposition.

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  • - The study focused on creating pod-like FeSe/C nanocomposite catalysts through a process called MIL-88 selenide annealing for efficient nitrogen reduction reactions (eNRR).
  • - The resulting FeSe/C nanocatalyst demonstrated impressive performance, achieving an ammonia yield rate of 7.11 μg h mg and a faradaic efficiency (FE) of 10.44% at an optimal potential of -0.3 V.
  • - Additionally, the FeSe/C electrocatalyst showed strong selectivity and stability, making it a promising candidate for future applications in nitrogen reduction.
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  • Hybrid tin-lead (Sn-Pb) perovskites are important for improving the efficiency of tandem solar cells but face challenges like Sn oxidation and fast crystallization that hurt their performance.
  • Researchers introduced an additive called 2-amino-3-mercaptopropanoic acid hydrochloride (AMPH), which helps stabilize Sn during film preparation and slows down crystallization, resulting in higher-quality films.
  • With AMPH, single-junction perovskite solar cells achieved a power conversion efficiency of 23.07%, and tandem cells reached a certified efficiency of 27.83%, maintaining over 85% efficiency after 500 hours of use.
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  • - The development of rechargeable zinc-air batteries is hindered by poor bifunctional catalysts and complex three-phase interfaces, creating a need for better solutions.
  • - The researchers introduced a flexible catalyst called Ru-NiFe LDH, which adapts its form during charging and discharging to optimize oxygen reactions, enhancing battery performance.
  • - Their innovative design includes a layered air cathode to improve oxygen bubble release and reduce carbon damage, resulting in significant enhancements in battery capacity, efficiency, and lifespan.
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Glass nano/micron pipettes, owing to their easy preparation, unique confined space at the tip, and modifiable inner surface of the tip, can capture the ion current signal caused by a single entity, making them widely used in the construction of highly sensitive and highly selective electrochemical sensors for single entity analysis. Compared with other solid-state nanopores, their conical nano-tip causes less damage to cells when inserted into them, thereby becoming a powerful tool for the analysis of important substances in cells. However, glass nanopipettes have some shortcomings, such as poor mechanical properties, difficulty in precise preparation (aperture less than 50 nm), and easy blockage during complex real sample detection, limiting their practicability.

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  • - Metal halide perovskites are considered effective materials for X-ray detection due to their strong ability to absorb X-rays, tolerance to defects, and potential for manufacturing large-area detectors at low temperatures.
  • - However, a significant challenge with these materials is their high ion conductivity, which leads to issues like increased dark current and instability in detector performance.
  • - The study presents a solution by adding PFH to perovskite films, which helps lower ion conductivity, cut down dark current, and improve overall detector sensitivity and stability, achieving a low detection limit of 14.7 nGy/s.
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The advancement of rechargeable zinc-air batteries (RZABs) faces challenges from the pronounced polarization and sluggish kinetics of oxygen reduction and evolution reactions (ORR and OER). Single-atom catalysts offer an effective solution, yet their insufficient or singular catalytic activity hinders their development. In this work, a dual single-atom catalyst, FeCo-SAs, was fabricated, featuring atomically dispersed N-Fe-Co-N sites on N-doped graphene nanosheets for bifunctional activity.

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The electrocatalytic nitrogen reduction reaction (eNRR) under ambient conditions is deemed a promising alternative for NH synthesis. In this paper, an FeP-FeO nanocomposite electrocatalyst was prepared by phosphating annealing using FeO as a precursor, and the resulting FeP-FeO exhibited excellent N-to-NH-producing activity over a wide potential window. The highest faradaic efficiency of FeP-FeO is 11.

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  • * This study focuses on new microcrystals of formamidinium lead iodide (FAPbI), synthesized in water, achieving a high purity of up to 99.996% which allows for large-scale production from cheaper raw materials.
  • * Using these purified materials, the researchers achieved a power conversion efficiency of 25.6% for inverted PSCs, with a significant retention of 94% efficiency after 1000 hours of testing under simulated conditions.
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A reduced graphene oxide encapsulating FeNiCoMnCu@rGO catalyst is prepared using a Joule heating strategy. The graphene-coated layer with high crystallinity enhances the stability of the crystal structure, resulting in superior OER activity. Rechargeable zinc-air batteries with FeNiCoMnCu@rGO demonstrate remarkable performance, boasting a high specific capacity of 800 mA h g, an impressive peak power density of 154.

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  • * IHI showed maximum solubility in DMF + ethanol and minimum solubility in DMF + water, indicating a co-solvency phenomenon in several mixtures.
  • * Four thermodynamic models were applied to analyze solubility data, with the Yaws model and modified Apelblat model providing the best fit, confirming that all models sufficiently represent IHI
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Benefiting from the synergistic development of material design, device engineering, and the mechanistic understanding of device physics, the certified power conversion efficiencies (PCEs) of single-junction non-fullerene organic solar cells (OSCs) have already reached a very high value of exceeding 19%. However, in addition to PCEs, the poor stability is now a challenging obstacle for commercial applications of organic photovoltaics (OPVs). Herein, recent progress made in exploring operational mechanisms, anomalous photoelectric behaviors, and improving long-term stability in non-fullerene OSCs are highlighted from a novel and previously largely undiscussed perspective of engineering exciton and charge carrier pathways.

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Solid-state nanopores/nanochannels, with their high stability, tunable geometry, and controllable surface chemistry, have recently become an important tool for constructing biosensors. Compared with traditional biosensors, biosensors constructed with solid-state nanopores/nanochannels exhibit significant advantages of high sensitivity, high specificity, and high spatiotemporal resolution in the detection single entities (such as single molecules, single particles, and single cells) due to their unique nanoconfined space-induced target enrichment effect. Generally, the solid-state nanopore/nanochannel modification method is the inner wall modification, and the detection principles are the resistive pulse method and the steady-state ion current method.

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Formamidinium lead triiodide (α-FAPbI ) has been widely used in high-efficiency perovskite solar cells due to its small band gap and excellent charge-transport properties. Recently, some additives show facet selectivity to generate a (001) facet-dominant film during crystallization. However, the mechanism to realize such (001) facet selectivity is not fully understood.

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  • Post-treatment is crucial for improving the performance of perovskite solar cells (PSCs) by passivating defects, especially in tin-lead mixed PSCs, but the choice of passivation agents has been underexplored.
  • This study focuses on using different isomers of trifluoromethyl-phenylethylamine hydroiodide (CF-PEAI) as surface treatments, revealing that the position of the -CF group impacts the dipole moment and, consequently, the power conversion efficiency (PCE) of the solar cells.
  • The para-position isomer, with the highest dipole moment, achieves a PCE of 20.17% and improves the open-circuit voltage from 0
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The charge transfer between the donor and acceptor determines the photogenerated carrier density in organic solar cells. However, a fundamental understanding regarding the charge transfer at donor/acceptor interfaces with high-density traps has not been fully addressed. Herein, a general correlation between trap densities and charge transfer dynamics is established by adopting a series of high-efficiency organic photovoltaic blends.

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The crystalline morphology of perovskite film plays a key role in determining the stability and performance of perovskite solar cells (PSCs). In addition, the work function and conductivity of hole transport layer (HTL) have a great influence on the effciency of PSCs. Here, we develop a synergistic doping strategy to fabricate high-performance inverted PSCs, doping a functional nanographene (C-AHM) into the poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine (PTAA) HTL, thus forming an HTL with higher conductivity, lower roughness, and frontier energy levels matching the perovskite absorber work function.

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Iris localization in non-cooperative environments is challenging and essential for accurate iris recognition. Motivated by the traditional iris-localization algorithm and the robustness of the YOLO model, we propose a novel iris-localization algorithm. First, we design a novel iris detector with a modified you only look once v4 (YOLO v4) model.

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Wide-bandgap perovskites as a class of promising top-cell materials have shown great promise in constructing efficient perovskite-based tandem solar cells, but their intrinsic relatively low radiative efficiency results in a large open-circuit voltage () deficit and thereby limits the whole device performance. Reducing film flaws or optimizing interfacial energy level alignments in wide-bandgap perovskite devices can efficiently inhibit nonradiative recombination to boost device and efficiency. However, the simultaneous regulation on both sides and their underlying mechanism are less explored.

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Here, the authors report a highly efficient integrated ideal-bandgap perovskite/bulk-heterojunction solar cell (IPBSC) with an inverted architecture, featuring a near infrared (NIR) polymer DTBTI-based bulk-heterojunction (BHJ) layer atop guanidinium bromide (GABr)-modified FA MA Pb Sn I perovskite film as the photoactive layer. The IPBSC shows cascade-like energy level alignment between the charge-extractionlayer/perovskite/BHJ and efficient passivation effect of BHJ on perovskite. Thanks to the well-matched energy level alignment and high-quality ideal bandgap-based perovskite film, an efficient charge transfer occurs between the charge-extraction-layer/perovskite/BHJ.

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A HSO-TiCT ion-gel is fabricated to prevent the restacking of TiCT for high-rate micro-supercapacitors. The ion-gel pillared by an electrolyte possesses an enlarged interlayer spacing facilitating ion transport. Furthermore, a bilayer structure is designed with dry TiCT for fast electron conduction.

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Employing low-dimensional perovskite has been proven to be a promising approach to enhance the efficiency and stability of perovskite solar cells. Here, thiopheniformamidine hydrochloride is introduced into CH NH PbI -based printable mesoscopic perovskite solar cells, to form 1D iodide lead thiophenamidine (TFPbI ) in situ. This judiciously designed low-dimensional perovskite can effectively passivate the defect of perovskite and induce the perovskite crystals to grow in a direction perpendicular to the substrate.

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To explore the effect of the introduction of heteroatoms on the properties of porphyrin materials, a new porphyrin-based derivative small-molecule donor named as PorTT-T was designed and synthesized based on alkyl-thieno[3,2-]thiophene(TT)-substituted porphyrins. The linker bridge and end groups of PorTT-T were the same as those of XLP-II small-molecule donor materials, while the side-chain attached to the core of thieno[3,2-]thiophene(TT)-substituted porphyrin was different. Measurements of intrinsic properties showed that PorTT-T has wide absorption and appropriate energy levels in the UV-visible range.

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