Publications by authors named "Yantao Shi"

Solution-processed perovskite solar cells (PSCs) generally suffer from serious Pb-based defects, and the issue becomes more pronounced during the upscaling process. A universal strategy that bridges small-area devices and large-area modules is imperative for advancing PSC technology from the lab toward market readiness. Here, to effectively address the Pb-based defect proliferation issues of perovskite surfaces, an ,-maleoyl-glycine (NMG) post-treatment anchoring strategy was proposed.

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Carbon-based perovskite solar cells (C-PSCs) exhibit notable stability and durability. However, the power conversion efficiency (PCE) is significantly hindered by energy level mismatches, which result in interfacial charge transport barriers at the electrode-related interfaces. Herein, we report a back electrode that utilizes atomically dispersed metallic cobalt (Co) in carbon nanosheets (Co/CN) to adjust the interfacial energy levels.

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Perceived COVID-19 crisis strength has been associated with teachers' emotional labor, but little is known about the mediating and moderating mechanisms underlying this association. This study aimed to explore whether interpersonal stress would mediate the relationship between perceived COVID-19 crisis strength and emotional labor, and whether gender would moderate the indirect pathway between perceived COVID-19 crisis strength and interpersonal stress. Participants were 889 primary-and secondary-school teachers from Guangxi, China, selected using convenient sampling method.

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The chemical property of the buried interface plays a crucial role in improving the performance and stability of perovskite solar cells (PSCs). The SnO/perovskite interface prepared from SnO alkaline hydrogel with high proton affinity triggers directional migration and irreversible reactions of protons, exacerbating the disintegration of perovskite crystal. In this study, we proposed proton precompensation strategy to suppress the deprotonation effect of the buried interface and improve the durability of the devices.

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Carbon nanotubes feature one-dimensional nature of collective excitations, wherein strong confinement of surface plasmons severely hinders the liberation of hot electrons (HEs), posing grand challenges for their utilization in photochemistry. In this study, we prototypically achieved directed HEs flow and extraction in hybrid plasmonic CNN based on cup-stacked carbon nanotubes (CSCNTs), taking advantage of their privileged edge-plane sites. The localized p electronic states and accessible intersubband plasmon excitations in the near-infrared (NIR) regime stands in striking contrast to the conventional concentric carbon nanotubes, as evidenced by combined photo-induced force microscopy (PiFM) and transient photocurrent response.

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The inverted perovskite solar cells (PSCs) are gaining increasing attention recently for their unprecedented advantages, such as better integration with tandem and flexible designs, negligible hysteresis, good operational stability, and compatibility with commercially scalable fabrication approaches. Nickel oxide (NiOx) films prepared by magnetron sputtering technology exhibit excellent scalability and reproducibility, which could well meet the requirements of the large-scale production of inverted PSCs. However, NiOx prepared by vacuum methods generally has fewer surface hydroxyl groups, deteriorating the wettability and damaging the interface contact with the perovskite.

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Perovskite solar cells (PSCs) have led to distinguished achievements and become one of the state-of-the-art photovoltaic technologies. Undoubtedly, reliable preparation of large area high-quality perovskite (PVK) films with uniform optoelectronic properties has become a critical and challenging task to transition PSCs from lab to market. Here, methyldiphenylphosphine oxide (MDPPO) is employed as an additive in a PVK precursor solution to promote uniform conductivity and carrier transport of PVK films.

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Antisolvent engineering is routinely used to modulate the crystallization of perovskite films as they can offer an additional driving force for nucleation. Actually, the intervention of antisolvent into nucleation is thought to involve some relatively fast and complex processes, which, however, are not fully understood so far. Here, the diffusion of the organic amine cation FA (one dominated precursor) and its distribution in a spin-coating process in different antisolvents is simulated by the computational fluid dynamics (CFD) model.

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Understanding the nature of single-atom catalytic sites and identifying their spectroscopic fingerprints are essential prerequisites for the rational design of target catalysts. Here, we apply correlated in situ X-ray absorption and infrared spectroscopy to probe the edge-site-specific chemistry of Co-N-C electrocatalyst during the oxygen reduction reaction (ORR) operation. The unique edge-hosted architecture affords single-atom Co site remarkable structural flexibility with adapted dynamic oxo adsorption and valence state shuttling between Co and Co , in contrast to the rigid in-plane embedded Co -N counterpart.

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Article Synopsis
  • Recent research highlights the use of Lewis acid-base chemistry to passivate defects in perovskite solar cells (PSCs), enhancing their power conversion efficiency (PCE) and stability.
  • Two Lewis base molecules, M (with carbonyl groups) and 3M (with both carbonyl and carboxyl groups), were studied to see which better mitigates Pb-based defects in PSCs.
  • The 3M molecule showed stronger bonding with uncoordinated Pb and achieved a high PCE of 24.07%, along with significantly improved operational stability for the modified solar cells.
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Cluster of Differentiations 73 (CD73)/ecto-5'-nucleotidase (NT5E) is a novel type of immune molecular marker expressed on many tumor cells and involved in regulating the essential immune functions and affecting the prognosis of cancer patients. However, it is not clear how the NT5E is linked to the infiltration levels of the immune cells in pan-cancer patients and their final prognosis. This study explores the role of NT5E in 33 tumor types using GEPIA, TIMER, Oncomine, BioGPS databases, and several bioinformatic tools.

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Cations with suitable sizes to occupy an interstitial site of perovskite crystals have been widely used to inhibit ion migration and promote the performance and stability of perovskite optoelectronics. However, such interstitial doping inevitably leads to lattice microstrain that impairs the long-range ordering and stability of the crystals, causing a sacrificial trade-off. Here, we unravel the evident influence of the valence states of the interstitial cations on their efficacy to suppress the ion migration.

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Early transition metals offer promising orthogonal reactivity to catalytic processes promoted by late transition metals. Nevertheless, exploiting variable single-atomic configurations as reactive centers is hitherto not well documented owing to their oxophilic nature. Herein we report an - grafting strategy that employs nitrogenated holey carbon nitrides as a scaffold and invokes the reasonably good match of temperature-dependent pyrolysis to stabilize an atomic titanium-nitrogen (TiNOH) moiety onto the hierarchical porous carbon support (Ti/NC-SAC).

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The feature endowing atomic Ni-N-C electrocatalysts with exceptional intrinsic alkaline hydrogen evolution activity is hitherto not well-documented and remains elusive. To this end, we rationally exploited the hierarchical porous carbon microstructures as scaffolds to construct unique Ni-N-S active sites to boost the sluggish Volmer reaction kinetics. Density functional theory reveals an obvious d-band center (ϵ) upshift of the edge-hosted Ni-N-S sites compared with pristine Ni-N, which translates to a more stabilized OH adsorption.

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Two-dimensional (2D) and quasi-2D Ruddlesden-Popper (RP) phase organolead halide perovskites are promising materials for both photovoltaic and optoelectronic devices. Although they are known to be more stable when exposed to moisture than their 3D counterpart, chemical degradation of these materials under moisture, which not only leads to a significant drop in device performance but also leads to lead leakage, yet remains one of the most serious hurdles for their practical applications. To gain insight into the degradation mechanism of 2D/quasi-2D perovskites under moisture conditions, the degradation pathway of 2D/quasi-2D (PEA)(MA) PbI (PEA = CHCHNH , MA = CHNH , and is the number of perovskite layers between adjacent organic spacer layers) perovskite single crystals (SCs) and thin film are explored.

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Interfacial passivation engineering plays a crucial role in the explosive development of perovskite solar cells (PSCs). However, previous studies on passivation layers mainly focused on the defect-passivation mechanism rather than the interfacial charge transport efficiency. Here, by precisely tuning the interplanar spacing of the ammonium iodide passivation layer, we elucidate the promoting effect of the reduced interplanar spacing of the passivation layer on the photogenerated hole tunneling efficiency at the interface of the hole transport layer and perovskite.

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In perovskite solar cells (PSCs), the hole-transport layer (HTL) plays an essential role in effective charge transport and extraction from the photoexcited perovskite, thus being significant for overall power conversion efficiency (PCE) and operational stability. So far, spiro-MeOTAD has been the most widely used HTL despite its inherent drawbacks, such as highly hygroscopic nature, poor conductivity, and mismatched energy-level alignment with the perovskite active layer. Here, a spiro-MeOTAD-based composite HTL modified by microwave method-synthesized carbon quantum dots (CQDs) was proposed and demonstrated as a promising HTL candidate for high-performance PSCs.

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We develop two discrete models to study how supplemental releases affect the spreading dynamics in cage mosquito populations. The first model focuses on the case when only infected males are released at each generation. This release strategy has been proved to be capable of speeding up the persistence by suppressing the compatible matings between uninfected individuals.

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An unsupported nanoporous platinum-iron bimetallic catalyst (PtFeNPore) was prepared with an electrochemical dealloying technique. Its structure and composition were characterized through various measurement methods, such as X-ray absorption fine structure (XAFS) and X-ray photoelectron spectroscopy (XPS). An intermetallic compound and iron oxide species were both found in the PtFeNPore catalyst.

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Herein, a 7.35 wt% Co loading C-SAC is synthesized by pyrolysis of Co-MOF-74 in a strongly polar molten salt system. In dye-sensitized solar cells, this SAC based counter electrode shows higher photoelectric conversion efficiency than the Pt counter electrode.

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We report a combination of experimental and computational mechanistic studies for the photoreduction of CO to CO with water, catalyzed by single-atom Fe supported on graphitic carbon nitride (g-CN). Density functional theory (DFT) and time-dependent DFT (TDDFT) methods were utilized to explore the behavior of single-atom Fe in g-CN, which is of vital importance to the understanding of the CO reduction reaction (CORR) mechanism. The calculation results reveal that the rate-limiting step of the hydrogen-bonded complex in the absence of Fe atoms is the cleavage of C-O bonds in COOH radicals during the whole CORR, which includes the photophysical and photochemical processes.

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The perovskite solar cell has emerged rapidly in the field of photovoltaics as it combines the merits of low cost, high efficiency, and excellent mechanical flexibility for versatile applications. However, there are significant concerns regarding its operational stability and mechanical robustness. Most of the previously reported approaches to address these concerns entail separate engineering of perovskite and charge-transporting layers.

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Carbon-supported single-atom catalysts (C-SACs) demonstrate great potential in various key electrochemical reactions. Nevertheless, the development of facile and economical strategies is highly appealing yet challenging given that the commonly used pyrolysis method has strict requirements on the structure and composition of precursors. Here, we demonstrate for the first time a facile and low-cost pyrolysis strategy assisted by molten salts at high temperature for preparing porous C-SACs with well-dispersed Co-N sites directly from a Chlorella precursor.

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As an indispensable component of perovskite solar cells (PSCs), the commonly used Au and Ag electrodes still have some problems such as high cost and instability issues with regard to being corroded by iodide ions. In this paper, we report stacking perovskite solar cells (S-PSCs), which can avoid the use of precious metal electrodes and reduce the cost of devices and the requirements of equipment compared to conventional PSCs. The S-PSCs are composed of two semicells: a photoanode and a counter electrode (CE).

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In this article, we formulate and study a discrete equation model depicting the pattern of infection in a mosquito population. A domain in [Formula: see text] is called a infection enhancing (or decaying) domain if in which the infection frequency of the next generation is always bigger (or smaller) than that of the current generation. We first give a complete analysis of the equivalent infection frequency curves.

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