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Highlights Two pre-crystallization processes of gas quenching and vacuum quenching lead to different order of crystallization dynamics within the perovskite thin film, resulting in the differences of additive distribution. A tailor designed 1,3-bis(4-methoxyphenyl)thiourea was utilized to improve the buried interface, leading to a certified efficiency of 23.75% for blade-coated perovskite solar cell. The perovskite solar module (aperture area: 60.84 cm2) demonstrates an efficiency of 20.18% with excellent operational stability (maximum power point tracking of T90 > 1000 h).

Abstract Lithium (Li) dendrite growth significantly deteriorates the performance and shortens the operation life of lithium metal batteries. Capturing the intricate dynamics of surface localized and rapid mass transport at the electrolyte–electrode interface of lithium metal is essential for the understanding of the dendrite growth process, and the evaluation of the solutions mitigating the dendrite growth issue. Here we demonstrate an approach based on an ultrasensitive tilted fiber Bragg grating (TFBG) sensor which is inserted close to the electrode surface in a working lithium metal battery, without disturbing its operation. Thanks to the superfine optical resonances of the TFBG, in situ and rapid monitoring of mass transport kinetics and lithium dendrite growth at the nanoscale interface of lithium anodes have been achieved. Reliable correlations between the performance of different natural/artificial solid electrolyte interphases (SEIs) and the time-resolved optical responses have been observed and quantified, enabling us to link the nanoscale ion and SEI behavior with the macroscopic battery performance. This new operando tool will provide additional capabilities for parametrization of the batteries’ electrochemistry and help identify the optimal interphases of lithium metal batteries to enhance battery performance and its safety.

High performance flexible all-thin-film electrochromic devices (ATF-ECDs) have been fabricated and systematically investigated by operating with different driving voltages during the electrochromic processes. The device structure (cross-section) and material properties of some main functional layers were presented and analysed. The electrochromic properties including kinetic and spectral tests were systematically investigated through combining chronoamperometry, cyclic voltammetry measurements and optical measurements. In addition, the open circuit memory measurement was also carried out. A much higher driving voltage might lead to a current leakage inside the device during coloring process. A proper driving voltage is needed for achieving high device performances. More details were widely described and deeply discussed.

Highlights A graded inverted solar cell configuration is developed by hole-transport management aiming to suppress interface defects-induced non-radiative recombination for efficient hole transport. NiO x -based inverted PSCs present a power-conversion-efficiency over 23% with a high fill factor of 0.84 and open-circuit voltage of 1.162 volts, one of the best performances reported so far for 1.56-electron volt bandgap formamidinium-based triple-halide perovskites. Devices show high operational stability over 1,200 h during T90 lifetime measurement under 1-sun illumination in ambient-air conditions.

Perovskite (PVK) solar cells (PSCs) have garnered considerable research interest owing to their cost-effectiveness and high efficiency. A systematic annual review of the research on PSCs is essential for gaining a comprehensive understanding of the current research trends. Herein, systematic analysis of the research papers on PSCs reporting key findings in 2023 was conducted. Based on the results, the papers were categorized into six classifications, including regular n–i–p PSCs, inverted p–i–n PSCs, PVK-based tandem solar cells, PVK solar modules, device stability, and lead toxicity and green solvents. Subsequently, a detailed overview and summary of the annual research advancements within each classification were presented. Overall, this review serves as a valuable resource for guiding future research endeavors in the field of PSCs.

Perovskite solar cells have aroused a worldwide research upsurge in recent years due to their soaring photovoltaic performance, ease of solution processing, and low cost. The power conversion efficiency record is constantly being broken and has recently reached 26.1% in the lab, which is comparable to the established photovoltaic technologies such as crystalline silicon, copper indium gallium selenide and cadmium telluride (CdTe) solar cells. Currently, perovskite solar cells are standing at the entrance of industrialization, where huge opportunities and risks coexist. However, towards commercialization, challenges of up-scaling, stability and lead toxicity still remain, the proper handling of which could potentially lead to the widespread adoption of perovskite solar cells as a low-cost and efficient source of renewable energy. This review gives a holistic analysis of the path towards commercialization for perovskite solar cells. A comprehensive overview of the current state-of-the-art level for perovskite solar cells and modules will be introduced first, with respect to the module efficiency, stability and current status of industrialization. We will then discuss the challenges that get in the way of commercialization and the corresponding strategies to address them, involving the upscaling, the stability and the lead toxicity issue. Insights into the future direction of commercialization of perovskite photovoltaics was also provided, including the flexible perovskite cells and modules and perovskite indoor photovoltaics. Finally, the future perspectives towards commercialization are put forward.

Abstract Indoor photovoltaics (IPVs) are expected to power the Internet of Things ecosystem, which is attracting ever‐increasing attention as part of the rapidly developing distributed communications and electronics technology. The power conversion efficiency of IPVs strongly depends on the match between typical indoor light spectra and the band gap of the light absorbing layer. Therefore, band‐gap tunable materials, such as metal‐halide perovskites, are specifically promising candidates for approaching the indoor illumination efficiency limit of ∼56%. However, perovskite materials with ideal band gap for indoor application generally contain high bromine (Br) contents, causing inferior open‐circuit voltage (VOC). By fabricating a series of wide‐bandgap perovskites (Cs0.17FA0.83PbI3−xBrx, 0.6 ≤ x ≤ 1.6) with varying Br contents and related band gaps, it is found that, the high Br vacancy (VBr) defect density is a significant reason that leading to large VOC deficits apart from the well‐accepted halide segregation. The introduction of I‐rich alkali metal small‐molecule compounds is demonstrated to suppress the VBr and increase the VOC of perovskite IPVs up to 1.05 V under 1000 lux light‐emitting diode illumination, one of the highest VOC values reported so far. More importantly, the modules are sent for independent certification and have gained a record efficiency of 36.36%.

Abstract In the past decades, the inverted structure (p‐i‐n structure) perovskite solar cells (PVSCs) have been attracted more by the researchers owing to their ease of fabrication, cost‐effectiveness, lower processing temperature for the fabrication of large scale and flexible devices with negligible J−V hysteresis effects. The hole transporting layer (HTL) as a major served content of PVSCs has significant influence on light harvesting, carrier extraction and transportation, perovskite crystallization, stability and cost. Generally, the organic materials are used as HTLs which have less stability due to their morphology under thermal conditions; thus, leads to change in properties of them. A tantalizing possibility is replacement of p‐type inorganic materials instead of organic materials but the plenty of options are available for inorganic HTLs. However, the development of more variants for inorganic HTL is a major challenge. Till date, many materials have been reported, but their performances have not superseded that of their organic counterparts. Herein, the review on various inorganic HTLs based inverted PVSCs has been reported and analyzed their performances with appropriate properties such as proper energy level and high carrier mobility which are not only assisted with charge transport, but also improved the stability of PVSCs under ambient conditions.

A high‐performance semitransparent perovskite solar cell (PSC) with small photovoltage loss is highly desired to achieve efficient and stable perovskite/silicon tandem solar cells. Herein, a synergistic passivation strategy is developed to suppress the electronic defects at both the grain boundary and surface of a perovskite layer (Cs0.05FA0.82MA0.13Pb(I2.86Br0.14)). It is found that the incorporation of a small amount of sodium fluoride (NaF) into perovskite precursor solution modulates the crystallization process, which results in large crystal grains with enhanced conductivity at the grain boundaries. Meanwhile, a thin 2D perovskite layer is constructed on the surface of the 3D perovskite film by solution coating a layer of phenethylammonium iodide (PEAI), which passivates the surface defects and improves the stability of perovskite films. As a consequence, the optimized semitransparent p–i–n PSC delivers a high power conversion efficiency (PCE) of 17.55% with an open‐circuit voltage of 1.11 V. Combining the semitransparent PSCs with a silicon cell, the efficiency of the four‐terminal perovskite/silicon tandem solar cells reaches a PCE of 23.82%.

Abstract Flexible perovskite solar cells (f‐PSCs) have attracted increasing attention because of their enormous potential for use in consumer electronic devices. The key to achieve high device performance is to deposit pinhole‐free, uniform and defect‐less perovskite films on the rough surface of polymeric substrates. Here, a solvent engineering to tailor the crystal morphology of FA‐alloyed perovskite films prepared by one‐step blade coating is first deployed. It is found that the use of binary solvents DMF:NMP, rather than the conventional DMF:DMSO, enables to deposit dense and uniform FA‐alloyed perovskite films on both the rigid and flexible substrates. As a decisive step, an embedding 2D/3D perovskite heterostructure is in situ formed by incorporating a small amount of 4‐guanidinobutanoic acid (GBA). Accordingly, photovoltage increases up to 100 mV are realized due to the markedly suppressed nonradiative recombination, leading to high efficiencies of 21.45% and 20.16% on the rigid and flexible substrates, respectively. In parallel, improved mechanical robustness of the flexible devices is achieved due to the presence of the embedded 2D phases. The results underpin the importance of morphology control and defect passivation in delivering high‐performance flexible FA‐alloyed flexible perovskite devices.

Abstract Antimony selenide (Sb2Se3) nanorod arrays along the [001] orientation are known to transfer photogenerated carriers rapidly due to the strongly anisotropic one‐dimensional crystal structure. With advanced light‐trapping structures, the Sb2Se3 nanorod array‐based solar cells have excellent broad spectral response properties, and higher short‐circuit current density than the conventional planar structured thin film solar cells. However, the interface engineering for the Sb2Se3 nanorod array‐based solar cell is more crucial to increase the performance, because it is challenging to coat a compact buffer layer with perfect coverage to form a uniform heterojunction interface due to its large surface area and length–diameter ratio. In this work, an intermeshing In2S3 nanosheet‐CdS composite as the buffer layer, compactly coating on the Sb2Se3 nanorod surface is constructed. The application of In2S3‐CdS composite buffers build a gradient conduction band energy configuration in the Sb2Se3/buffer heterojunction interface, which reduces the interface recombination and enhances the transfer and collection of photogenerated electrons. The energy‐level regulation minimizes the open‐circuit voltage deficit at the interfaces of buffer/Sb2Se3 and buffer/ZnO layers in the Sb2Se3 solar cells. Consequently, the Sb2Se3 nanorod array solar cell based on In2S3‐CdS composite buffers achieves an efficiency of as high as 9.19% with a VOC of 461 mV.

Antimony selenide is a promising thin film solar cell absorber material in which grain orientation is crucial for high device performance. Here Li et al. grow the material in nanorod arrays along the [001] direction and obtain record high efficiency of 9.2%.

Abstract Environmentally benign and potentially cost‐effective Sb2Se3 solar cells have drawn much attention by continuously achieving new efficiency records. This article reports a compatible strategy to enhance the efficiency of planar n–i–p Sb2Se3 solar cells through Sb2Se3 surface modification and an architecture with oriented 1D van der Waals material, trigonal selenium (t‐Se). A seed layer assisted successive close spaced sublimation (CSS) is developed to fabricate highly crystalline Sb2Se3 absorbers. It is found that the Sb2Se3 absorber exhibits a Se‐deficient surface and negative surface band bending. Reactive Se is innovatively introduced to compensate the surface Se deficiency and form an (101) oriented 1D t‐Se interlayer. The p‐type t‐Se layer promotes a favored band alignment and band bending at the Sb2Se3/t‐Se interface, and functionally works as a surface passivation and hole transport material, which significantly suppresses interface recombination and enhances carrier extraction efficiency. An efficiency of 7.45% is obtained in a planar Sb2Se3 solar cell in superstrate n–i–p configuration, which is the highest efficiency for planar Sb2Se3 solar cells prepared by CSS. The all‐inorganic Sb2Se3 solar cell with t‐Se shows superb stability, retaining ≈98% of the initial efficiency after 40 days storage in open air without encapsulation.

Organic-inorganic perovskite solar cells (PSCs) have achieved an inspiring third-party-certificated power conversion efficiency (PCE) of 25.2%, which is comparable with commercialized silicon (Si) and copper indium gallium selenium solar cells. However, their notorious instability, including their deterioration at elevated temperature, is still a serious issue in commercial applications. This thermal instability can be ascribed to the high volatility and reactivity of organic compounds. As a result, solar cells based on inorganic perovskite materials have drawn tremendous attention, owing to their excellent stability against thermal stress. In the last few years, PSCs based on inorganic perovskite materials have seen an astonishing development. In particular, CsPbI3 and CsPbI2Br PSCs demonstrated outstanding PCEs, exceeding 18% and 16%, respectively. In this review, we systematically discuss the properties of inorganic perovskite materials and the device configuration of inorganic PSCs as well as review the progress in PCE and stability. Encouragingly, all-inorganic PSCs, in which all functional layers are inorganic, provide a feasible approach to overcome the thermal instability issue of traditional organic-inorganic PSCs, leading to new perspectives toward commercial production of PSCs.

Abstract Metal halide perovskite solar cells (PSCs) have raised considerable scientific interest due to their high cost‐efficiency potential for photovoltaic solar energy conversion. As PSCs already are meeting the efficiency requirements for renewable power generation, more attention is given to further technological barriers as environmental stability and reliability. However, the most major obstacle limiting commercialization of PSCs is the lack of a reliable and scalable process for thin film production. Here, a generic crystallization strategy that allows the controlled growth of highly qualitative perovskite films via a one‐step blade coating is reported. Through rational ink formulation in combination with a facile vacuum‐assisted precrystallization strategy, it is possible to produce dense and uniform perovskite films with high crystallinity on large areas. The universal application of the method is demonstrated at the hand of three typical perovskite compositions with different band gaps. P‐i‐n perovskite solar cells show fill factors up to 80%, underpinning the statement of the importance of controlling crystallization dynamics. The methodology provides important progress toward the realization of cost‐effective large‐area perovskite solar cells for practical applications.

Abstract Sb2S3 has attracted great research interest very recently as a promising absorber material for photoelectric and photovoltaic devices because of its unique optical and electrical properties and single, stable phase. However, the intrinsic high resistivity property of Sb2S3 material is one of the major factors restricting the further improvement of its application. In this work, the C60 modification of Sb2S3 thin films is investigated. The conductivity of Sb2S3 thin films increases from 4.71 × 10−9 S cm−1 for unmodified condition to 2.86 × 10−8 S cm−1 for modified thin films. Thin‐film solar cells in the configuration of glass/(SnO2:F) FTO/TiO2/Sb2S3(C60)/Spiro‐OMeTAD/Au are fabricated, and the conversion efficiency is increased from 1.10% to 1.74%.

Pure-sulphide Cu2ZnSnS4 (CZTS) thin film solar cells were prepared by a low-cost, non-toxic and high-throughput method based on the thermal decomposition and reaction of sol–gel precursor solution, followed by a high temperature sulfurization process in sulphur atmosphere, which usually gave rise to the unexpected Cu-poor and Zn-rich phase after sulfurization. In order to remove the formation of detrimental secondary phases, e.g. ZnS, a novel method with hydrochloric acid solution treatment to the CZTS absorber layer surface was employed. By using this method, a competitive power conversion efficiency as high as 4.73% was obtained, which is a factor of 4.8 of that of the control CZTS solar cell without surface treatment. This presents a customized process for CZTS photovoltaic technologies that is more environmentally friendly and considerably less toxic than the widely used KCN etching approach.

Rational structure design of 3D hosts is one of the most promising strategies to achieve uniform Li deposition and inhibit the uncontrolled growth of Li dendrites. Herein, a 3D-CTPA skeleton with lithiophobic–lithiophilic properties was used for the fabrication of a 3D composite Li anode (3D-CTPA@Li) by electrodeposition. The resulting 3D-CTPA@Li symmetric cell showed a long lifespan of 2000 h at 1 mA cm−2 for 1 mA h cm−2. Additionally, the 3D-CTPA@Li/LiFePO4 full cell exhibited long cyclic stability with 86.6% capacity retention after 500 cycles at 0.5C. The good electrochemical performance of the 3D-CTPA@Li anode can be attributed to the unique features of the 3D-CTPA skeleton, which resulted in dominant Li(110) facets for enhanced electrochemical kinetics. This was supported by XPS results, which indicated the formation of an inorganic-rich SEI layer on the surface of the 3D-CTPA@Li anode. The robust SEI layer with heterogenous electronic insulated/ionic conductive (Li3N/LiF) properties could effectively inhibit the reduction of Li+ and the electrolyte on the surface of the 3D-CTPA@Li anode, as well as serve as an “ionic sieve” to realize uniform and fast Li+ transport through the interface. Consequently, metallic Li preferentially nucleated/grew inside the 3D-CTPA pore spaces with bottom-up Li deposition. [ABSTRACT FROM AUTHOR]

To overcome the efficiency limit of perovskite single-junction solar cells, it is vital to develop various types of tandem solar cells. Especially, wide-bandgap (WBG) perovskite solar cells (PSCs) have played an important role in high-efficiency tandem solar cells. Herein, an indium zinc oxide-based interfacial structure is developed to improve the performance of a WBG PSC and used as the transparent electrode for semitransparent (ST) PSCs. This approach minimizes ohmic contact between the electron-transport layer and metallic electrode, which also accelerates electron transfer and suppresses trap-assisted carrier recombination. As a result, the WBG PSC (1.71 eV) shows the best power conversion efficiency of 19.26% and improves operational stability. When the optimized ST-PSC is used as the ST-top cell, perovskite/CdTe four-terminal and perovskite/silicon (doubleside polished) two-terminal tandem solar cells achieve a maximum efficiency of 22.59% and 26.34%, respectively. [ABSTRACT FROM AUTHOR]

A hysteresis loop of minority carrier lifetime vs voltage is found in polystyrenesulfonate (PSS)/Si organic-inorganic hybrid heterojunctions, implying an interfacial memory effect. Capacitance-voltage and conductance-voltage hysteresis loops are observed and reveal a memory window. A switchable interface state, which can be controlled by charge transfer based on an electrochemical oxidation/deoxidation process, is suggested to be responsible for this hysteresis effect. We perform first-principle total-energy calculations on the influence of external electric fields and electrons or holes, which are injected into interface states on the adsorption energy of PSS on Si. It is demonstrated that the dependence of the interface adsorption energy difference on the electric field is the origin of this two-state switching. These results offer a concept of organic-inorganic hybrid interface memory being optically or electrically readable, low-cost, and compatible with the flexible organic electronics. [ABSTRACT FROM AUTHOR]

Light-induced degradation has been identified to be a critical issue for most silicon-based solar cell technologies. This study presents an observation of an opposite light-induced enhancement (LIE) effect in photovoltaic performance in poly(3,4-ethylthiophene):polystyrenesulfonate/n-Si organicinorganic hybrid solar cells. The reduced density of interface states under light soaking (LS) is found to be responsible for the LIE of the hybrid solar cells. An increased minor carrier lifetime under LS and a switchable photoluminescence intensity while applying a voltage bias are observed, providing evidence for the underlying physical mechanism [ABSTRACT FROM AUTHOR]

The use of polystyrenesulfonate (PSS) thin films in a high-quality passivation scheme involving the suppression of minority carrier recombination at the silicon surface is presented. PSS has been used as a dispersant for aqueous poly-3,4-ethylenedioxythiophene. In this work, PSS is coated as a form of thin film on a Si surface. A millisecond level minority carrier lifetime on a high resistivity Si wafer is obtained. The film thickness, oxygen content, and relative humidity are found to be important factors affecting the passivation quality. While applied to low resistivity silicon wafers, which are widely used for photovoltaic cell fabrication, this scheme yields relatively shorter lifetime, for example, 2.40 ms on n-type and 2.05 ms on p-type wafers with a resistivity of 1-5 Ω·cm. However, these lifetimes are still high enough to obtain high implied open circuit voltages (Voc) of 708mV and 697mV for n-type and p-type wafers, respectively. The formation of oxides at the PSS/Si interface is suggested to be responsible for the passivation mechanism. [ABSTRACT FROM AUTHOR]

A series of BaIn6Y2O13:Yb3+, Er3+, Tm3+ phosphors with different dopant concentrations have been successfully synthesized by a sol-gel method. In order to obtain efficient white light emitting samples, tri-doped and biphasic samples were prepared. Afterwards, we carried out a systematic study on the upconversion luminescence (UCL) properties of the samples as functions of doping concentrations and excitation densities. The up-conversion (UC) white light emission powers and efficiencies of samples with different dopant concentrations at different excitation power densities were obtained. The highest white UCL efficiency of up to 0.38% was achieved at excitation densities down to 17.5 W cm-2 in the biphasic samples. More importantly, we demonstrated that the UC materials with higher efficiency do not necessarily have stronger emission power, and the emission power is the most important parameter. A maximum emission power of up to 1.23 mW was obtained. Furthermore, the impact of temperature on the white UCL was studied, and transparent polymer composites that can emit white light were synthesized by doping BaIn6Y2O13 samples into polymethylmethacrylate (PMMA). [ABSTRACT FROM AUTHOR]

The epitaxial-Si (epi-Si) growth on the crystalline Si (c-Si) wafer could be tailored by the working pressure in plasma-enhanced chemical vapor deposition (PECVD). It has been systematically confirmed that the epitaxial growth at the hydrogenated amorphous silicon (a-Si:H)/c-Si interface is suppressed at high pressure (hp) and occurs at low pressure (lp). The hp a-Si:H, as a purely amorphous layer, is incorporated in the lp-epi-Si/c-Si interface. We find that: (i) the epitaxial growth can also occur at a-Si:H coated c-Si wafer as long as this amorphous layer is thin enough; (ii) with the increase of the inserted hp layer thickness, lp epi-Si at the interface is suppressed, and the fraction of a-Si:H in the thin films increases and that of c-Si decreases, corresponding to the increasing minority carrier lifetime of the sample. Not only the epitaxial results, but also the quality of the thin films at hp also surpasses that at lp, leading to the longer minority carrier lifetime of the hp sample than the lp one although they have the same amorphous phase. [ABSTRACT FROM AUTHOR]

In this work, we present an alternative route to supply excessive selenium (Se) for the deposition of Sb2Se3 thin films by the co-evaporation of Se and Sb2Se3. Scanning electron microscopy (SEM) images showed that additional Se modified the growth process and surface morphology of Sb2Se3 thin films. X-ray diffraction (XRD) patterns confirmed that this co-evaporation process enhanced the beneficiary preferred orientations, and capacitance–voltage (C–V) measurement showed that the carrier concentration of the Sb2Se3 absorber increased with the additional evaporation of Se. Accordingly, the efficiency of the devices employing co-evaporated Sb2Se3 absorber layers increased significantly from 2.1 to 3.47% with a open-circuit voltage (VOC) of 364 mV, a short-circuit current density (JSC) of 23.14 mA/cm2, and a fill factor (FF) of 41.26%. [ABSTRACT FROM AUTHOR]

A series of BaIn6Y2O13:Yb3+, Er3+, Tm3+ phosphors with different dopant concentrations have been successfully synthesized by a sol-gel method. In order to obtain efficient white light emitting samples, tri-doped and biphasic samples were prepared. Afterwards, we carried out a systematic study on the upconversion luminescence (UCL) properties of the samples as functions of doping concentrations and excitation densities. The up-conversion (UC) white light emission powers and efficiencies of samples with different dopant concentrations at different excitation power densities were obtained. The highest white UCL efficiency of up to 0.38% was achieved at excitation densities down to 17.5 W cm-2 in the biphasic samples. More importantly, we demonstrated that the UC materials with higher efficiency do not necessarily have stronger emission power, and the emission power is the most important parameter. A maximum emission power of up to 1.23 mW was obtained. Furthermore, the impact of temperature on the white UCL was studied, and transparent polymer composites that can emit white light were synthesized by doping BaIn6Y2O13 samples into polymethylmethacrylate (PMMA). [ABSTRACT FROM AUTHOR]