Tin‐based halide perovskites attract incremental attention due to the favorable optoelectronic properties and ideal bandgaps. However, the poor crystalline quality is still the biggest challenge for ...further progress in tin‐based perovskite solar cells (PVSCs) due to the unfavorable defects and uncontrollable crystallization kinetics. Here, acetic acid (HAc) is first introduced to reduce the supersaturated concentration of the precursor solution to preferentially form pre‐nucleation clusters, thus inducing rapid nucleation for effective regulation of crystallization kinetics. In particular, the hydrogen ion and acetate ion contained in HAc can effectively inhibit the oxidation of Sn2+, and the hydrogen bonding interaction between HAc and iodide ion (I‐) greatly reduces the loss of I‐, which guarantees the I‐/Sn2+ stoichiometric ratio of the corresponding perovskite film close to theoretical value, thus effectively reducing the defect density and maintaining the perfect crystal lattice. Consequently, the HAc‐assisted tin‐based PVSCs achieve a champion power conversion efficiency of 12.26% with superior open‐circuit voltage up to 0.75 V. Moreover, the unencapsulated device maintains nearly 90% of the initial PCE even after 3000 h storage in nitrogen atmosphere. This demonstrated strategy enables to prepare high‐quality tin‐based perovskite film with lower defect density and lattice distortion.
Acetic acid (HAc) is first introduced to reduce the supersaturated concentration of the precursor solution to form pre‐nucleation clusters, thus inducing rapid nucleation. In particular, the introduction of HAc can inhibit the oxidation of Sn2+ and reduce the loss of I‐. HAc‐assisted device deliver a champion efficiency of 12.26%, maintaining ≈90% of initial efficiency after storage in nitrogen over 3000 h.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Interfacial lattice mismatch and adverse reaction are the key issues hindering the development of nickel oxide (NiOx)‐based inverted perovskite solar cells (PVSCs). Herein, a p‐chlorobenzenesulfonic ...acid (CBSA) self‐assembled small‐molecule (SASM) is adopted to anchor NiOx and perovskite crystals to endow dual‐passivation. The chlorine terminal of SASMs can provide growth sites for perovskite, leading to interfacial strain release. Meanwhile, the sulfonic acid group from SASMs can passivate surface defects of NiOx, conducive to charge carrier extraction. In addition, the self‐assembled layer inhibits the adverse interfacial reaction by preventing NiOx contact with perovskite. Therefore, the NiOx/CBSA‐based PVSCs obtain a champion power conversion efficiency (PCE) of 21.8%. Of particular note, the unencapsulated devices can retain above 80% of their initial PCE values after storage in a nitrogen atmosphere for 3000 h, in air with a relative humidity of 50–70% for 1000 h, and heating at 85 °C for 800 h, respectively.
A p‐chlorobenzenesulfonic acid (CBSA)‐based self‐assembled layer dual‐passivation strategy is employed to effectively eliminate interfacial lattice mismatch and detrimental reactions in NiOx‐based perovskite solar cells, which achieves unencapsulated devices preserving above 80% of initial efficiencies after storing in N2 for 3000 h, in air with a relative humidity of 50–70% for 1000 h, and heating at 85 °C for 800 h, respectively.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The perovskite film prepared by traditional two-step sequential deposition possesses numerous defects and excess lead iodide (PbI
2
), which is mainly due to the formation of a dense PbI
2
layer and ...the incomplete solid-liquid reaction. It has been shown that the presence of the PbI
2
species has some positive effects on the power conversion efficiency (PCE), but the random distribution of excess PbI
2
can be detrimental to the device stability. Herein, we demonstrate the feasibility of fabricating a porous PbI
2
layer with ordered array structure by integrating a succinamide (SA) additive with a nanoimprinting technology, which can confine the organic amine salts in PbI
2
arrays to facilitate the omnidirectional diffusion and realize sufficient conversion to perovskites. Consequently, an unencapsulated device (active area of 0.04 cm
2
) is obtained with 23.56% efficiency and excellent long-term humidity stability (∼90% efficiency retention after 1800 h) in ambient air (relative humidity of 50 ± 5%). Moreover, the fabricated perovskite solar cell (1.01 cm
2
) and module (14.63 cm
2
) achieve impressive efficiencies of 21.57% and 16.42%, respectively. This work paves the way for the expansion of the two-step sequential deposition method from the laboratory to the large-scale fabrication of high-performance perovskite photovoltaic devices.
The porous lead iodide layer with ordered arrays structure is firstly fabricated to facilitate the omnidirectional diffusion of organic amine salts and realize high quality large-area perovskite film in two-step sequential deposition.
Display omitted
•The interfacial redox reaction between NiOx and perovskite is obstructed.•SaC-100 is developed as a modifier layer in NiOx-based perovskite solar cells.•SaC-100 can efficiently ...reduce the open-circuit voltage loss of device.•SaC-100 can inhibit perovskite decomposition ascribed from interfacial reaction.
In NiOx-based perovskite solar cells (PVSCs), the interfacial redox reaction between Ni3+ (on the surface of NiOx) and A-site cation salt (MAI in perovskite precursor solution) is invariably ignored. This adverse reaction will generate PbI2-rich hole extraction barriers at the NiOx-perovskite interface, which limits hole transmission and increases charge recombination, thus resulting in open-circuit voltage (Voc) loss. Furthermore, it will accelerate perovskite degradation by deprotonating the precursor amine and oxidizing iodide to interstitial iodine, which induces the severe instability of devices. Herein, a physical separation strategy by introducing a modifier layer to obstruct the detrimental reaction is explored. The results demonstrate that the trimethylolpropane tris(2-methyl-1-aziridinepropionate) (SaC-100) depositing onto NiOx can suppress the reaction between Ni3+ and MAI to endow the improvement of conductivity and reduction of interfacial defects, thus reducing Voc loss and enhancing device stability. Moreover, the interfacial energy level alignment and the morphology of perovskite are also optimized. As a result, the PVSCs device based on NiOx/SaC-100 presents the best power conversion efficiency (PCE) of 20.21% with a superior Voc value of 1.12 V. Furthermore, the device shows better light and thermal stability because of the hindering effect and defect passivation effect of SaC-100.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Tin-based perovskite materials have attracted intensive research due to its environmental friendliness and tremendous potential in the photovoltaic field. However, the extremely poor crystalline ...quality and awful stability of tin-based perovskite have restricted the further improvement in optoelectronic performance. Herein, a novel strategy of crystal orientate manipulation is proposed by introducing a self-assembly molecule, fluorinated-perylene diimide (F-PDI), which provides an external driving force to guide the orientated crystallization of perovskite in the vertical direction, and thus greatly promotes the effective transmission of carriers. The conductive F-PDI simultaneously serves as defect passivator and hydrophobic barrier layer, which boosts the photoelectric performance and contributes to the lattice robustness. As a result, the unencapsulated device based on F-PDI achieves considerable power conversion efficiency (PCE) of 9.49% and exhibits remarkable long-term stability, maintaining over 80% of its original efficiency after ∼3000 h storage under light soaking.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
The effects from the molecular configuration of diammonium spacer cations on 2D/3D perovskite properties are still unclear. Here, we investigated systematically the mechanism of molecular ...configuration‐induced regulation of crystallization kinetic and carrier dynamics by employing various diammonium molecules to construct Dion‐Jacobson (DJ)‐type 2D/3D perovskites to further facilitating the photovoltaic performance. The minimum average Pb‐I‐Pb angle leads to the smallest octahedral tilting of PbX64− lattice in optimal diammonium molecule‐incorporated DJ‐type 2D/3D perovskite, which enables suitable binding energy and hydrogen‐bonding between spacer cations and inorganic PbX64− cages, thus contributing to the formation of high‐quality perovskite film with vertical crystal orientation, mitigatory lattice distortion and efficient carrier transportation. As a consequence, a dramatically improved device efficiency of 22.68 % is achieved with excellent moisture stability.
Various diammonium spacer cations are used to construct 2D/3D perovskite. The mechanism of molecular configuration‐induced regulation of crystal orientation and carrier dynamics is investigated. 2D/3D perovskite solar cells based on 2,2′‐(ethylenedioxy)bis(ethylamine) achieve a device efficiency of 22.68 % and excellent moisture stability, retaining 82 % of initial efficiency after aging at 50±5 % relative humidity for 1560 h.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Defect passivation is a key strategy to prepare high-performance perovskite solar cells (PVSCs). Even though abundant passivation molecules have been applied, the absence of detailed researches with ...regard to different functional groups in polymer additives may inevitably impede the establishment of passivation molecules selection rules. In this work, three passivation molecules including poly(vinyl alcohol) (PVA), polymethyl acrylate (PMA), and poly(acrylic acid) (PAA) are employed to systematically analyze the passivation effect from hydroxyl, carbonyl, and carboxyl groups. In general, PVA (−OH) can form hydrogen bonds with perovskite and PMA (−CO) can complex with uncoordinated Pb2+. Specifically, PAA (−COOH) can interact selectively with MA+ and I– ions via hydrogen bonding and complex with uncoordinated Pb2+ to passivate defects more effectively. Hence, the PAA-incorporated PVSCs based on MAPbI3 achieve the champion power conversion efficiency (PCE) of 20.29% with open-circuit voltage up to 1.13 V. In addition, PAA cross-linking perovskite grains can relieve mechanical stress, as well as occupy the major channels to suppress ion migration and water/oxygen erosion. The corresponding unencapsulated devices demonstrate a superior light soaking stability, retaining more than 80% of the original PCE under one sun illumination for 1000 h.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
Longevity is a key constraint for hybrid perovskite based photovoltaics. Here it is demonstrated that ion migration‐induced degradation can be eliminated by incorporation of multifunctional ...poly(ionic‐liquid)s (PILs) additives, resulting in ultrastable perovskite solar cells (PVSCs). The presence of PILs suffices to construct an “ionic polymer network,” providing the functionalities of defect passivation and ion immobilization by concurrently forming a physical barrier and chemical bonding. Compared with the defect passivation effect for the imidazolium‐based PIL (PIL‐Im) case, the quaternary ammonium‐based PIL (PIL‐Am) shows a higher interaction energy with the perovskite due to the stronger electronic coupling ascribed to the additional complexation, which endows the corresponding perovskite with higher migration energy for iodide ions. As a result, the power conversion efficiency (PCE) of anion‐cation‐mixed hybrid n‐i‐p PVSCs with PIL‐Am is remarkably improved from 20.26% to 22.22%. Specifically, the PILs‐modified device perfectly retains its dark current characteristics upon a cooling (−40 °C)–heating (85 °C) process. The unencapsulated PIL‐Am stabilized PVSC maintains 80% of the initial PCE under AM 1.5G light soaking for nearly 1500 h. The corresponding device also displays pronounced stability under thermal stress or realistic operation conditions.
Poly(ionic‐liquid)s (PILs) are employed to construct an “ionic polymer network” in perovskites for defect passivation and ion immobilization. The device that incorporates quaternary ammonium‐based PIL perfectly retains dark current characteristics during a cooling‐heating (−40–85 °C) process. The corresponding perovskite solar cells maintain 80% of their original efficiency under either 1500 h light‐soaking or 300 h thermal stress (85 °C).
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Tin-based perovskites are the most likely alternative candidates for lead-based counterparts due to their low toxicity and excellent optoelectronic properties. However, their uncontrollable ...crystallization process limits the improvement of device performance. Here, a green anti-solvent (acetic acid, HAc) has been first applied to adjust the crystallization process of tin-based perovskites, that is, to accelerate solution nucleation by salting-out crystallization and to slow down the crystal growth rate by hydrogen bond interactions. Furthermore, the non-volatilized residual HAc reduces the loss of organic amine salts and passivates defect states in the perovskites. Consequently, a device prepared using HAc realizes the highest efficiency of 12.78% (an open circuit voltage of 0.92 V) among non-chlorobenzene-based devices. Pioneeringly, we point out a general principle that the congeners of HAc, whose ability to form a hydrogen bond is not higher than that of HAc, can act as anti-solvents to prepare tin-based perovskites.
Pioneeringly, we point out a general principle for selecting an appropriate anti-solvent. Salting-out crystallization induced by a green anti-solvent (acetic acid, HAc) has been used for the first time to fabricate Sn-based PVSCs with an efficiency of 12.78%.
The limited solar spectrum utilization hinders the further amelioration of the performance of perovskite solar cells (PVSCs). An up-conversion (UC) process extends the spectral absorption of PVSCs ...from the visible to near-infrared (NIR) range and minimizes the sub-band-gap photon transmission loss. The perovskite-sensitized triplet-triplet annihilation (TTA) from rubrene (Rub) and dibenzotetraphenylperiflanthene (DBP) has shown great potential in UC applications. Herein, the TTA UC mechanism is introduced for the first time into PVSCs for converting NIR photons to visible photons, which facilitates the obvious improvement of photocurrent. Attributed to the TTA UC effect and energy band alignment of the Rub:DBP UC layer with the perovskite, the MAPbI
3
based PVSCs acquire a champion power conversion efficiency (PCE) of 20.18% accompanied by significant enhancements in the short circuit current density (
J
sc
) and open-circuit voltage (
V
oc
). In addition, rubrene doping can promote perovskite growth owing to the formation of π-conjugated agglomerates, which serve as the growing sites for perovskite crystallization nuclei. Furthermore, the Rub:DBP-based unencapsulated devices exhibit excellent moisture stability, and maintain more than 80% of the primitive PCE after 14 days of storage under air conditions (50-70% humidity, 25 °C).
The triplet-triplet annihilation upconversion layer Rub:DBP was introduced to extend the near-infrared response of perovskite solar cells, reduce the sub-band-gap photon transmission loss and ultimately facilitate the photovoltaic performance.
