Showing papers by "Anyi Mei published in 2019"
TL;DR: In situ back-contact passivation (BCP) that reduces interfacial and extraction losses between the perovskite absorber and the hole transport layer (HTL) is reported and it is shown that a flat-band alignment between theperovskites and polymer passivation layers achieves a high photovoltage and fill factor.
Abstract: Organic-inorganic hybrid perovskite solar cells (PSCs) have seen a rapid rise in power conversion efficiencies in recent years; however, they still suffer from interfacial recombination and charge extraction losses at interfaces between the perovskite absorber and the charge-transport layers. Here, in situ back-contact passivation (BCP) that reduces interfacial and extraction losses between the perovskite absorber and the hole transport layer (HTL) is reported. A thin layer of nondoped semiconducting polymer at the perovskite/HTL interface is introduced and it is shown that the use of the semiconductor polymer permits-in contrast with previously studied insulator-based passivants-the use of a relatively thick passivating layer. It is shown that a flat-band alignment between the perovskite and polymer passivation layers achieves a high photovoltage and fill factor: the resultant BCP enables a photovoltage of 1.15 V and a fill factor of 83% in 1.53 eV bandgap PSCs, leading to an efficiency of 21.6% in planar solar cells.
133 citations
114 citations
TL;DR: In this article, it is known that ion-migration-driven decomposition represents a degradation pathway in halide perovskite solar cells, which motivates further work to improve operating stability.
Abstract: Impressive progress in halide perovskite solar cells motivates further work to improve operating stability. It is known that ion-migration-driven decomposition represents a degradation pathway in p...
113 citations
TL;DR: The built-in electric field of the printable, hole-conductor-free mesoscopic perovskite solar cells based on these perovSKites with amide additives is enhanced, and a highest power conversion efficiency of 15.57% is obtained.
Abstract: Solution-processable organic-inorganic perovskite solar cells have attracted much attention in the past few years. Energy level alignment is of great importance for improving the performance of perovskite solar cells because it strongly influences charge separation and recombination. In this report, we introduce three amide additives, namely, formamide, acetamide, and urea, into the MAPbI3 perovskite by mixing them directly in perovskite precursor solutions. The Fermi level of MAPbI3 shifts from -4.36 eV to -4.63, -4.65, and -4.61 eV, respectively, upon addition of these additives. The charge transfer between perovskite and mp-TiO2 is found to be promoted as determined via TRPL spectra, and recombination in the perovskite is suppressed. As a result, the built-in electric field (Vbi) of the printable, hole-conductor-free mesoscopic perovskite solar cells based on these perovskites with amide additives is enhanced and a peak power conversion efficiency of 15.57% is obtained.
54 citations
TL;DR: The community is concerned about achieving industrial-scale, large-area manufacturing with high throughput for practical application of perovskite solar cells and urges the community to present the module performance and long-term stability data using standard methods and reliable measurement protocols.
53 citations
TL;DR: A low-temperature carbon electrode with good perovskite compatibility is employed in hole-transport-material free perovSkite solar cells, and a champion power conversion efficiency (PCE) of 11.7% is obtained.
34 citations
TL;DR: In this article, the authors proposed a printable perovskite solar cells (PSCs), which have attracted widespread attention due to the simple fabrication process and low-cost raw materials.
Abstract: Printable perovskite solar cells (PSCs) have attracted widespread attention due to the simple fabrication process and low-cost raw materials. However, because no hole transport material is used and...
32 citations
TL;DR: In this article, the authors developed a printable mesoscopic perovskite solar cells (PSCs) based on a triple layer scaffold of TiO2/ZrO 2/carbon.
Abstract: Screen printing technique has been widely applied for the manufacturing of both traditional silicon solar cells and emerging photovoltaics such as dye-sensitized solar cells (DSSCs) and perovskite solar cells (PSCs). Particularly, we have developed a printable mesoscopic PSC based on a triple layer scaffold of TiO2/ZrO2/carbon. The deposition of the scaffold is entirely based on screen printing process, which provides a promising prospect for low-cost photovoltaics. However, the optimal thickness of the TiO2 layer for fabricating efficient printable PSCs is much smaller than the typical thickness of screen printed films. Here, we tune the concentration of the pastes and the printing parameters for coating TiO2 films, and successfully print TiO2 films with the thickness of 500–550 nm. The correlation between the thickness of the films and printing parameters such as the solid content and viscosity of the pastes, the printing speed and pressure, and the temperature has been investigated. Besides, the edge effect that the edge of the TiO2 films possesses a much larger thickness and printing positional accuracy have been studied. This work will significantly benefit the further development of printable mesoscopic PSCs.
21 citations
TL;DR: In this system, dye LI-96 with BTD in the middle of conjugated bridge showed the broadest spectrum and achieved the best photovoltaic performance (8.25%), which may pave a new way to design or optimize the efficient sensitizers by rational design of acceptor position.
Abstract: With respect to cyanoacryclic acid as the traditional acceptor and anchoring group in dye-sensitized solar cells, the introduction of stronger electron-deficient groups has greatly expanded the sco...
16 citations
Abstract: The spacer layer is a key component of fully printable mesoscopic perovskite solar cells, but its precise characteristics are far from being understood in relation to the device design. In the present work, we perform a detailed systematic study on the effects of spacer parameters, such as size of building blocks, layer thickness, etc., on properties of the perovskite filler, insulating ability and performance of fully printable mesoscopic perovskite solar cells by combining the techniques of time-resolved photoluminescence, high-resolution TEM, insulating resistance measurements, impedance spectroscopy and J–V characteristics. Drawing on the deep understanding from these studies, we formulate key principles, which are anticipated to guide the design of the advanced spacer layer for fully printable mesoscopic perovskite solar cells.
14 citations
TL;DR: A new two-stage melt processing (TSMP) method for incorporating Se in printable triple mesoscopic solar cells in the ambient conditions and shows power conversion efficiency of 2 %, which is eight times of that for devices based on the single-stage melting processing.
Abstract: Hexagonal selenium with a direct band gap has been developed for optoelectronic applications for more than one century. The major advances in Se solar cells have been made using vacuum or solution-...
TL;DR: In this article, the authors measured and compared the parameters of printable mesoscopic perovskite solar cells with shading masks of different shapes and aperture areas, and established a model to calibrate the measured JSC, which was considered as a sum of effective JSC (JSC-eff) and error JSC-err.
Abstract: Perovskite solar cells (PSCs) have attracted intensive attention in the past several years due to their ever-increasing efficiency. Particularly, high efficiencies are usually obtained by small-area (≤0.1 cm2) lab cells, and thus, the cell performance can be easily over- or underestimated due to inappropriate measurement protocols. Shading masks with well-defined apertures are usually employed to determine the test area of the cells. However, it is found that the aperture area significantly influences the measured photovoltaic parameters of the cells, and has not been quantified. Here we measure and compare the parameters of printable mesoscopic PSCs with shading masks of different shapes and aperture areas. It is identified that extra diffuse light may go through the masks due to the edge effect, and cause an overestimation of the photocurrent density (JSC). We establish a model to calibrate the measured JSC, which is considered as a sum of effective JSC (JSC-eff) and error JSC (JSC-err). By fitting the JSC measured using apertures of 0.031–0.503 cm2 with a quadratic function, JSC-eff and JSC-err are respectively obtained. Besides the aperture areas, the ratio of aperture area/active area also influences the open-circuit voltage and fill factor of the cells. By fitting the measured values with different apertures, we establish a model to calibrate the measured parameters of PSCs. This model can evaluate the test errors and provide effective values of the photovoltaic parameters of PSCs.
Patent•
30 Apr 2019TL;DR: In this paper, a ferroelectric-enhanced solar cell was proposed, which replaces an ordinary thin film by using a Ferroelectric nano material having good crystallization, such as nano particles, such that residual polarization strength was higher, while not influencing the transmission of the carrier.
Abstract: Disclosed by the present invention are a ferroelectric-enhanced solar cell and a preparation method therefor, wherein the ferroelectric-enhanced solar cell comprises a conductive substrate (1), and a hole barrier layer (2), a mesoporous nanocrystalline layer (3), a mesoporous separation layer (4), and a mesoporous back electrode layer (5) that are sequentially deposited on the conductive substrate (1); the mesopores of at least one from among the mesoporous nanocrystalline layer (3), the mesoporous separation layer (4) and the mesoporous back electrode layer (5) are filled with an optical active material; at least one from among the hole barrier layer (2), the mesoporous nanocrystalline layer (3) and the mesoporous separation layer (4) comprises a ferroelectric material or a ferroelectric nano-composite material. The present invention replaces an ordinary thin film by using a ferroelectric nano material having good crystallization, such as nano particles, such that residual polarization strength is higher, while not influencing the transmission of the carrier; furthermore, an inorganic ferroelectric material processed by means of a special manual polarization process may further effectively promote the separation and transmission of the carrier.
Patent•
16 Apr 2019
TL;DR: In this article, a novel perovskite function material and application thereof in a photoelectric device is presented. But the perovsite function is applied to alloyed or modified perovskiite materials based on amidine molecules, and the pervskite materials are ABX3 perovkite materials, wherein A is univalent organic or inorganic positive ions, B is divalent metal positive ions and X is unival negative ions.
Abstract: The invention discloses a novel perovskite function material and application thereof in a photoelectric device. The novel perovskite function material is applied to alloyed or modified perovskite materials based on amidine molecules, and the perovskite materials are ABX3 perovskite materials, wherein A is univalent organic or inorganic positive ions, B is divalent metal positive ions, and X is univalent negative ions. The chemical expression of the amidine molecules is R-C(=NH)NH2, wherein R is any one of -NH2, -CH3 and -C6H5. According to specific application, the A-site positive ions in theperovskite materials are replaced with the positive ions of the amidine molecules, or the amidine molecules serve as an additive to be added to a base of the ABX3 perovskite materials. According to the novel perovskite function material and application thereof in the photoelectric device, the amidine molecules of a specific chemical structure are introduced into the ABX3 perovskite-based materials, the fluorescent lifetime of a carrier can be remarkably prolonged, the perovskite photoelectric function material excellent in optical and electrical performance can be obtained, the reparation process is simple, and the cost is low.
05 May 2019
TL;DR: In this paper, an all-passive, high-efficient, and coin-sized visible-to-telecom converter was proposed by hybrid packaging a perovskite detector with an integrated silicon photonic chip.
Abstract: We propose and fabricate an all-passive, high-efficient, and coin-sized visible-to-telecom converter by hybrid packaging a perovskite detector with an integrated silicon photonic chip. The converter can convert visible light signals into telecommunication band with 200 kHz modulated rate. © 2019 The Author(s)
Patent•
03 Dec 2019
TL;DR: In this article, an organic small molecule halide modified perovskite photoelectric functional material ABX3 was obtained by using organic halide small molecules, and a degree of crystallinity and a filling factor of perovsite can be remarkably increased, a preparation process method is simple and cost is low.
Abstract: The invention belongs to the photoelectric functional material technology field and especially relates to an organic small molecule halide modified perovskite photoelectric functional material, and preparation and an application thereof A general chemical formula is (M)z(A1)a(A2)b(A3)1-a-b-z(B1)c(B2)1-c(X1)d(X2)e(X3)3-d-e, the M is an organic small molecule halide, and the perovskite-based photoelectric functional material is obtained by modifying a perovskite-based photoelectric functional material ABX3 through using organic halide small molecules. By using the organic small molecule halide modified perovskite-based photoelectric functional material, a degree of crystallinity and a filling factor of perovskite can be remarkably increased, the perovskite photoelectric functional material with excellent electrical performance can be obtained, a preparation process method is simple and cost is low.