Wide Band Gap Research Articles

A cubic perovskite fluoride anode with the surface conversion reactions dominated mechanism for advanced lithium-ion batteries.

Perovskite fluorides are attractive anode materials for lithium-ion batteries (LIBs) because of their three-dimensional diffusion channels and robust structures, which is advantageous for the rapid transmission of lithium ions. Unfortunately, the wide band gap results in poor electronic conductivity, which limits their further development and application. Herein, the cubic perovskite iron fluoride (KFeF3, KFF) nanocrystals (~100 nm) are synthesized by a one-step solvothermal strategy. Thanks to the good electrical conductivity of carbon nanotubes (CNTs), the overall electrochemical performance of composite anode material (KFF-CNTs) has been significantly improved. In particular, the KFF-CNTs delives a high specific capacity (363.8 mAh g-1), good rate performance (131.6 mAh g-1 at 3.2 A g-1), and superior cycle stability (500 cycles). Noted that the surface conversion reactions play a dominant role in the electrochemical process of KFF-CNTs, together with the stable octahedral perovskite structure and nanoscale particle sizes achieving high ion diffusion coefficients. Furthermore, the specific lithium storage mechanism of KFF has explored by the distribution of relaxation times (DRT) technology. This work opens up a new way for developing cubic perovskite fluorides as high-capacity and robust anode materials for LIBs.

A Novel Cross Tetrachiral Honeycomb Metamaterial with Designable Static and Dynamic Performances.

A novel cross tetrachiral honeycomb metamaterial is proposed, which not only possesses the negative Poisson's ratio property, but also has a wide-frequency bandgap. The effective elastic parameters of the cross tetrachiral honeycomb are first theoretically analyzed; then, its designable performances for negative Poisson's ratio and elastic modulus are studied by varying geometric parameters. The dynamic properties of the cross tetrachiral honeycomb metamaterial are investigated by analyzing the band structure. It is shown that without the addition of external mass to the structure, a designable wide bandgap can be generated to isolate the in-plane waves effectively by selecting the ligament angles and the radius of central cylinder. In addition, an effective approach is proposed for tuning the bandwidth without changing the geometric parameters of the structure. Compared to classical negative Poisson's ratio metamaterials, the proposed cross tetrachiral honeycomb metamaterial is designable and tunable for achieving a specific static or dynamic performance, and has potential applications in engineering practice.

Structural, electronic and conductive properties of single wall MgGeN2 nanotube: A first principles investigation

MgGeN2 is a type II-IV-V2 semiconductor with a wide band gap which have previously been studied in bulk, monolayer, and multilayer form. We have investigated single wall MgGeN2 nanotubes in different orientations and diameters by ab initio calculations. It was found that the band gap is strongly dependent on the type and diameter of the tubes, ranging from 2.1 to 2.6 eV. Moreover, the migration of electrons is favored instead of holes. The obtained results also suggest that the radius- and orientation-dependent single wall MgGeN2 nano tubes are promising for optoelectronics and photocatalysis.

Theoretical Optimization of an Earth-Abundant and Environmentally Friendly Photovoltaic Absorber Cu3PSe4 from First-Principles Study to Device Simulation.

To seek an earth-abundant and environmentally friendly absorber for thin-film solar cells, Cu3PSe4 is investigated by first-principles calculations and device simulations. We demonstrate that the compound has a suitable band gap width of 1.3 eV as well as a high sunlight absorption coefficient. However, drawbacks like small electron affinity, high hole concentration, large lattice mismatch with CdS, etc., are revealed, which may degrade the photovoltaic performance. To address those shortcomings, we propose (1) to optimize the carrier concentration by preparing the samples at low temperature and under a Cu-rich environment, (2) to replace the CdS buffer layer by a more suitable wide-gap semiconductor with smaller lattice mismatch, and (3) that the selected buffer layer should have small electron affinity in order to reduce the open-circuit voltage losses. After implementation of these optimization approaches, the device simulations demonstrate that the power conversion efficiency reaches 17.7% for a solar cell with the configuration Mo/Cu3PSe4/WS2/n-ZnO. The combination of first-principles calculations at the atomistic level and device simulations at the macroscopic level provides an appropriate approach to design ideal solar cells.

Green synthesis of In2S3-supported Ni-MOF: Bifunctional photocatalyst for sustainable H2O2 production and 2,4,6-trinitrophenol photoreduction

This study describes a unique and sustainable strategy for synthesizing a highly effective photocatalyst using solvothermal synthesis to combine bioderived In2S3 and Nickel Metal-Organic Framework (Ni-MOF) forming In2S3/Ni-MOF. Bioderived In2S3 was produced using Azadirachta indica (neem) leaf extract, providing a green and sustainable source for semiconductor material synthesis. The synergistic interaction of In2S3 with Ni-MOF led to better charge transfer kinetics, a wider band gap, and reduced charge recombination, all contributing to increased photoactivity. The constructed photocatalyst performed admirably under visible light irradiation in producing hydrogen peroxide (H2O2) with an impressive 1528.5 μmol/g.h yield. Furthermore, the photocatalyst demonstrated extraordinary effectiveness in reducing 2,4,6-trinitrophenol (2,4,6-TNP), with a reduction efficiency of 96.31 % in 20 min and high reusability in both applications. The observed results highlight the importance of the collaborative impact between In2S3 and Ni-MOF, demonstrating the promise of this green-synthesized material as a highly efficient photocatalyst with dual uses in various environmental settings. Using renewable neem leaf extract to manufacture In2S3 adds an environmentally beneficial component to the entire strategy, helping to build sustainable and efficient photocatalytic materials.

Physics of Ferroelectric Wurtzite Al1−xScxN Thin Films

AbstractAl1−xScxN emerges as a revolutionary ferroelectric material within the III‐N family. It combines exceptional switchable polarization (80–165 µC cm−2), highly tunable coercive fields (1.5–6.5 MV cm−¹), and a wide bandgap (4.9–5.6 eV). Unlike conventional ferroelectrics, Al1−xScxN exhibits remarkable compatibility with both CMOS and III‐N technologies. It can be fabricated on plastic substrates at low temperatures, demonstrating excellent flexibility and biocompatibility. Remarkably, Al1−xScxN maintains superior performance in harsh environments due to its outstanding thermal stability (up to 1100 °C). These unique characteristics position Al1−xScxN as a highly promising candidate for a wide range of applications, including high‐performance memory, in‐memory computing, neuromorphic computing, and next‐generation wearable and implantable devices, particularly for operation in complex environments. Despite its potential, Al1−xScxN faces challenges such as high coercive fields, significant leakage currents, and limited polarization reversal cycle life. Addressing these challenges require a deeper understanding of the fundamental physics controlling Al1−xScxN films. This review explores the origins of Al1−xScxN's ferroelectricity and phase stability, delves into the fundamental theory of wurtzite ferroelectricity, investigates mechanisms for controlling spontaneous polarization and coercive fields, examines recent research progress in Al1−xScxN ferroelectric devices, and outlines future development directions for this exciting material.

Chemical Synergic Stabilization of High Br-Content Mixed-Halide Wide-Bandgap Perovskites for Durable Multi-Terminal Tandem Solar Cells with Minimized Pb Leakage.

High Br-content mixed-halide perovskites with wide-bandgap (WBG) of 1.6-2.0 eV have showcased vast potential to be used in tandem solar cells. However, they often suffer from severe halide segregation, phase separation and ion migration issues, which would accelerate the decomposition of perovskites films,deteriorate the photovoltaic performance and even aggravate the lead leakage from damaged devices. Here, we report a novel chemical synergic interaction strategy to mitigate the abovementioned issues. A small amount of cationic β-cyclodextrin, composed of multiple ammonium cations, chlorine ions and abundant hydroxyl functional groups, was introduced into WBG perovskites, which effectively stabilized the halide ions and homogenized the phase distribution, comprehensively passivated the defects,and efficiently immobilized the Pb2+ ions. Encouragingly, the cationic β-cyclodextrin was universal and useful for different WBG perovskites, which favorably boosted the efficiencies by 10%-36% and extended the device operational stability to 2680 h. The integrated four-terminal orsix-terminal all-perovskite tandem solar cells exhibited efficiencies up to 24.39% and 22.42%, respectively. We demonstrated the cationic β-cyclodextrin-assisted internal chemical encapsulation effectively prevented the Pb leakage from severely damaged devices with only 5.63 ppb Pb leaching out. The target tandem solar cells with cationic β-cyclodextrin modification also realized a Pb sequestration efficiency of 93.4%.

Chemical Synergic Stabilization of High Br‐Content Mixed‐Halide Wide‐Bandgap Perovskites for Durable Multi‐Terminal Tandem Solar Cells with Minimized Pb Leakage

High Br‐content mixed‐halide perovskites with wide‐bandgap (WBG) of 1.6‐2.0 eV have showcased vast potential to be used in tandem solar cells. However, they often suffer from severe halide segregation, phase separation and ion migration issues, which would accelerate the decomposition of perovskites films, deteriorate the photovoltaic performance and even aggravate the lead leakage from damaged devices. Here, we report a novel chemical synergic interaction strategy to mitigate the abovementioned issues. A small amount of cationic β‐cyclodextrin, composed of multiple ammonium cations, chlorine ions and abundant hydroxyl functional groups, was introduced into WBG perovskites, which effectively stabilized the halide ions and homogenized the phase distribution, comprehensively passivated the defects,and efficiently immobilized the Pb2+ ions. Encouragingly, the cationic β‐cyclodextrin was universal and useful for different WBG perovskites, which favorably boosted the efficiencies by 10%‐36% and extended the device operational stability to 2680 h. The integrated four‐terminal or six‐terminal all‐perovskite tandem solar cells exhibited efficiencies up to 24.39% and 22.42%, respectively. We demonstrated the cationic β‐cyclodextrin‐assisted internal chemical encapsulation effectively prevented the Pb leakage from severely damaged devices with only 5.63 ppb Pb leaching out. The target tandem solar cells with cationic β‐cyclodextrin modification also realized a Pb sequestration efficiency of 93.4%.

Three-Supercenter Two-Electron Bonds in C16H10: Two-Dimensional Analogue of Halogen-Bridge Bonding.

Three-center two-electron bridging bonding plays a vital role in rationalizing structures and stabilities of certain molecules. Herein, the π electron rule of pyrene (C16H10) was unraveled based on a newly proposed two-dimensional (2D) superatomic-molecule theory, where the superatomic sextet rule was regarded as a π electron counting target. C16H10 can be taken as a ◊N2◊F2 superatomic molecule, where ◊N and ◊F denote 2D superatoms bearing 3π and 5π electrons, respectively. Interestingly, it represents the first 2D superatomic halogen-bridge molecule, which realizes π electronic shell-closure via two three-supercenter two-electron bridging bonds. Additionally, a N-doped nanoporous graphene with a wide band gap (1.22 eV) was designed based on C16H10, which can be considered as a periodic aggregate of 2D superatomic wires composed of 2π-◊C and bridging ◊F superatoms. This work enriches the 2D superatomic-molecule chemistry and provides a practicable bottom-up assemble approach to obtain 2D functional materials with tunable band gaps.

Precise control of photogenerated carrier behavior of zinc oxide through band reconstruction to enhance photocatalytic treatment of dye wastewater

In the field of photocatalytic treatment of dye wastewater, zinc oxide (ZnO) is a typical semiconductor photocatalyst, but it has some disadvantages such as wide band gap, low carrier yield and easy recombination. In this study, Cr-ZnO/N-CQDs catalyst was synthesised using the strategy of p-type doping and construction of Z-scheme heterojunction. The results showed that the removal rate of Cr-ZnO/N-CQDs for MB dye was 97.42 %, which was 70.56 % higher than that of ZnO, and was still 92.16 % after 5 cycles, and the TOC removal rate of methylene blue wastewater was 88.60 %. The reason for the enhanced photocatalytic activity of Cr-ZnO/N-CQDs is that the π* electron (e−) in the N-CQDs interact with the 3d orbitals of Cr-ZnO, so that e− is more easily transferred from the valence band of Cr-ZnO to the conduction band of N-CQDs. The band gap of p-type Cr-ZnO is narrowed, which makes its photogenerated carrier yield increase, hole concentration raise, and the adsorption capacity of H2O molecules reduce by 1.04 eV. The density functional theory calculation shows that the maximum Gibbs free energy of Cr-ZnO for the production of hydroxyl radical is 0.05 eV lower than that of ZnO. This study lays theoretical and practical foundation for the photocatalytic treatment of dye wastewater with ZnO.

Magnetic-assisted alignment of nanofibers in a polymer nanocomposite for high-temperature capacitive energy storage applications.

Flexible polymer-based dielectrics with high energy storage characteristics over a wide temperature range are crucial for advanced electrical and electronic systems. However, the intrinsic low dielectric constant and drastically degraded breakdown strength hinder the development of polymer-based dielectrics at elevated temperatures. Here, we propose a magnetic-assisted approach for fabricating a polyethyleneimine (PEI)-based nanocomposite with precisely aligned nanofibers within the polymer matrix, and with Al2O3 deposition layers applied on the surface. The resulting polymer nanocomposite exhibits simultaneously increased dielectric constant and enhanced breakdown strength at high temperatures compared to pristine PEI. The enhanced dielectric constant is contributed by the depolarization effect of out-of-plane orientated nanofibers in composite films, while the surficial Al2O3 layers, with a wide bandgap, effectively prevent charge injection and transport at the electrode/dielectric interface. The optimally aligned composite films exhibit a significantly enhanced discharged energy density of 6.5 J cm-3 at 150 °C, with approximately 41% and 132% enhancement compared to random films and pristine PEI films, respectively. Additionally, a metalized multilayer polymer-based capacitor utilizing this composite film produces a high capacitance of 88 nF, while demonstrating excellent cyclability and flexibility at 150 °C. This work offers an effective strategy for developing polymer-based composite dielectrics with superior capacitive performance at elevated temperatures and demonstrates the potential of fabricating high-quality flexible capacitors.

Perovskite-Like Carbodiimides AB(NCN)3: Synthesis and Characterization of MnHf(NCN)3 and FeHf(NCN)3.

Two novel ternary air-stable transition-metal carbodiimides, MnHf(NCN)3 and FeHf(NCN)3, were synthesized via solid-state metathesis using either ZnNCN or Na2NCN as the carbodiimide source and the corresponding binary metal chlorides. These two phases are the first examples of transition-metal carbodiimides with an AB(NCN)3 composition, akin to ubiquitous ABO3 perovskite oxides. The crystal structure of MnHf(NCN)3 was determined and refined from powder X-ray diffraction (XRD) data in the non-centrosymmetric space group P6322 allowing for chirality, the assignment of which is supported by second-harmonic generation (SHG) measurements. FeHf(NCN)3 was found to crystallize isotypically, and the presence of iron(II) in a high spin state was confirmed by 57Fe Mößbauer spectroscopy. The structures are revealed to be NiAs-derived and can be described as a hexagonal stack of NCN2- anions with metal cations occupying 2/3 of the octahedral voids. Both IR spectroscopic measurements and DFT calculations agree that the NCN2- unit is a bent carbodiimide with C2v symmetry, necessary to account for the size difference present in such a vacancy-ordered structure. Magnetic studies reveal predominantly strong antiferromagnetic interactions but no long-range order between the paramagnetic Mn2+ centers, likely due to the dilution of Mn2+ over the octahedral sites or perhaps even due to some degree of magnetic frustration. The optical and electrochemical properties of MnHf(NCN)3 were then studied, revealing a wide band gap of 3.04 eV and p-type behavior.

Rational Molecular Design of Phenanthroimidazole-Based Fluorescent Materials toward High-Efficiency Deep-Blue OLEDs by Molecular Isomer Engineering.

Organic light-emitting diodes (OLEDs) have been extensively investigated in full-color displays and energy-saving lighting owing to their unique advantages. However, deep-blue OLEDs based on nondoped emitting layers with a satisfactory external quantum efficiency (EQE) are still rare for applications. In this work, six hot exciton materials, PPIM-12F, PPIM-22F, PPIM-13F, PPIM-23F, PPIM-1CN, and PPIM-2CN, are designed and synthesized via an isomer engineering design strategy and their photophysical properties and OLED performance are systematically investigated. These emitters all possess wide band gaps (3.53-3.69 eV), hybrid local and charge transfer (HLCT) characteristics, and good thermal stabilities. The C2 series compounds, PPIM-22F, PPIM-23F, and PPIM-2CN, all show redder emission peaks than the N1 series counterparts of PPIM-12F, PPIM-13F, and PPIM-1CN. In addition, the LUMO energy levels decrease consecutively in the sequence of PPIM-22F < PPIM-23F < PPIM-2CN and are all lower than their respective N1 series position isomers of PPIM-12F, PPIM-13F, and PPIM-1CN. The CV measurements indicate that such a design strategy renders the fine-tuning of LUMO energy levels, and the incorporation of electron acceptors at the extended C2 position of the PI unit is a better choice to improve the electron injection ability. Theoretical simulations indicate that they may harvest the triplet exciton through an upper-level reverse intersystem crossing process, which decreases the gathering of triplet excitons and allows the OLEDs to be fabricated by nondoping technology. Among them, PPIM-22F with a difluorobenzene substituent at the C2 position manifests the best performance in OLEDs, which exhibits the maximum EQE of 7.87% and Commission Internationale de ĺEclairage (CIE) coordinates of (0.16, 0.10). This work demonstrates an effective strategy for considerable improvement in device performance by a subtle change in the molecular structure through isomer engineering.

High power deep ultraviolet radiation generation from short pulse laser induced electron–hole pair production in a wide bandgap semiconductor

High power deep ultraviolet radiation generation from short pulse laser induced electron–hole pair production in a wide bandgap semiconductor

TiO2/AgSbO3 nanophotocatalyst with improved photocatalytic performance in the synthesis of some benzimidazole derivatives

Due to the fact that TiO2 semiconductor has a profound surface and a porous structure, this compound shows a high photocatalytic activity among other similar counterparts. The wide band gap of TiO2 (∼3.2 eV) and existing defects in the structure of this material provides desirable efficacy to enhance absorption of visible-region of the solar energy. Therefore, introducing narrower band-gap semiconductors next to TiO2 is an effective route to expand the range of sunlight absorption in composite photocatalysts. The purpose of this research is to prepare TiO2/AgSbO3 nanophotocatalyst by the well-known hydrothermal method, then, characterized by FT-IR, XRD, EDX, DRS, and FE-SEM. After that, the nanophotocatalyst was performed in the multi-component synthesis of some pharmaceutically important 2-substituted benzimidazoles. This study confirmed that hydroxyl radical, superoxide anion radical, and holes are viable contributing mediators in the photocatalytic process. Speeding up the reaction, green nature, cost-effectiveness and non-toxicity of the nanophotocatalyst are highlight features of the present protocol.

Insight into the Structural and Performance Correlation of Photocatalytic TiO2/Cu Composite Films Prepared by Magnetron Sputtering Method

Photocatalysis technology, as an efficient and safe environmentally friendly purification technique, has garnered significant attention and interest. Traditional TiO2 photocatalytic materials still face limitations in practical applications, hindering their widespread adoption. The research prepared TiO2/Cu films with different Cu contents using a magnetron sputtering multi-target co-deposition technique. The incorporation of Cu significantly enhances the antibacterial properties and visible light response of the films. The effects of different Cu contents on the microstructure, surface morphology, wettability, antibacterial properties, and visible light response of the films were investigated using an X-ray diffractometer, X-ray photoelectron spectrometer, field emission scanning electron microscope, confocal laser scanning microscope, Ultraviolet–visible spectrophotometer, and contact angle goniometer. The results showed that the prepared TiO2/Cu films were mainly composed of the rutile TiO2 phase and face-center cubic Cu phase. The introduction of Cu affected the crystal orientation of TiO2 and refined the grain size of the films. With the increase in Cu content, the surface roughness of the films first decreased and then increased. The water contact angle of the films first increased and then decreased, and the film exhibited optimal hydrophobicity when the Cu target power was 10 W. The TiO2/Cu films showed good antibacterial properties against Escherichia coli and Staphylococcus aureus. The introduction of Cu shifted the absorption edge of the films to the red region, significantly narrowed the band gap width to 2.5 eV, and broadened the light response range of the films to the visible light region.

Fluorinated Polythiophenes with Alkylthiophene Side Chains Boosting the Performance of Wide Bandgap Perovskite Solar Cells.

Wide bandgap (WBG) perovskite solar cells (PSCs) provide their merit of high voltage output but are faced with the overdeepened valence band and the notorious phase segregation. Herein, two alkylthiophene-substituted polythiophenes (PT4T-0F and PT4T-2F) are applied as the interfacial layer for the WBG (1.72 eV) PSCs. Compared with PT4T-0F, PT4T-2F with fluoride (F) on thiophene units in a conjugated backbone exhibits more planar configuration, higher hole mobility, and deeper highest occupied molecular orbital energy. By using PT4T-2F as an additive in antisolvent, crystal growth of FA0.83Cs0.17Pb(I0.7Br0.3)3 is successfully mediated, resulting in high ratio (100) plane exposure of the WBG perovskites, and defect passivation is simultaneously realized. The optimized device presents a high open-circuit voltage of 1.23 V and a power conversion efficiency of 19.20%. The long-term stabilities under moisture and thermal conditions are both improved. This work offers an ideal interlayer material for WBG PSC engineering and further provides a simple process to integrate simultaneous crystal mediation and interface optimization.

Inorganic Semiconductor-Based Flexible UV Photodetector Arrays Achieved by Specific Flip-Chip Bonding.

In recent years, flexible UV photodetectors (PDs) with complex environmental adaptability and great wearability have attracted the attention of researchers worldwide. Wide bandgap inorganic semiconductor materials with excellent optoelectronic properties and mechanical stability are key functional materials for UV PD devices. However, the high temperature processing and inherent brittleness limit the further application of high-quality inorganic semiconductors in the field of flexible optoelectronics. In this work, we develop a specific flip-chip bonding fabrication technique that utilizes high-temperature treated inorganic semiconductor materials for high-performance flexible UV detection devices. Leveraging this technique, a 7 × 7 pixel flexible UV photodetector array (UV-FPDA) device based on a vertical architecture Mg-doped ZnO/NiO (Mg:ZnO/NiO) heterojunction transistor is built. The UV-FPDAs exhibit a high responsivity of 75.8 A/W and an outstanding detectivity of 8.5 × 1012 Jones. Besides, the UV-FPDAs also demonstrate excellent bending stability. Furthermore, the photoresponse characteristics of each pixel are trained and learned by an artificial neural network to achieve clear imaging of UV light information. Our results provide a new pathway for the application of inorganic semiconductors in the field of high-performance flexible UV photodetection.

Inverse design of phononic topological pumping in continuous solids

Topological insulators have been widely studied for their unique properties, particularly their ability to propagate energy with minimal losses in a manner that is robust to structural defects. More recently, topological pumping, which provides a mechanism to transport energy from one location to another in a structure without the need for direct coupling between the locations, has emerged as a phenomena of interest. However, previous studies on topological pumping of phonons have been performed without developing an understanding of how the efficiency of the pumping, as well as control over the pumping pathway in continuous solids, can be systematically controlled. Therefore, in this work we introduce a novel framework for the inverse design of continuous structures that can exhibit topological pumping of phonons, that is based on two key steps: (I) shape design of unit cells that not only exhibit topologically non-trivial edge states, but whose edge states span a wide range of phase values and wavenumbers at the excitation frequency to achieve a robust pumping effect; (II) optimizing the functional form to enable nonlinear modulation of the phase, which enables control both over the pumping path, and also the efficiency of the energy transport along the desired pumping pathway. Using this approach, we are able to establish connections between the dynamical properties of the unit cell, and various properties that impact the pumping efficiency, including the bandgap width, wavevector range, unit cell truncation, and the path of the phase modulation. We further demonstrate the ability to perform pumping for both out-of-plane and in-plane elastic waves, as well as for quantum valley Hall-based topological insulators.

Toward sustainable manufacturing of highly efficient and stable semi-transparent perovskite solar cells: The critical role of green solvent properties

Perovskite solar cells, promising a bright future in the energy market, are now being prioritized for high-throughput production to match their remarkable success at the laboratory scale. However, the use of toxic solvents proved to be one of the major constraints on scaling up production. Herein, a green solvent system consist of dimethyl sulfoxide (DMSO) and 1-dodecyl-3-methylimidazolium chloride ([C12MIM]Cl) ionic liquids (ILs) was developed to modulate the crystallization of wide-bandgap (WBG) perovskite films combined with a antisolvent-free process, i.e., nitrogen (N2) quenching method. The [C12MIM]Cl IL promoted the crystallization of WBG perovskite films with large grain sizes, reduced photo-active PbI2, modulated residual strain, prolonged carrier lifetimes as well as improved energy alignment. Consequently, the [C12MIM]Cl-modified single-junction 1.77 eV perovskite solar cells (PSCs) achieved a champion efficiency of 18.75 % with an excellent operational stability, retaining an initial PCE of 93 % after 2000 h of maximum-power-point tacking test. Meanwhile, the positive effect of the [C12MIM]Cl ILs was universal in perovskite with different bandgaps at 1.53, 1.68 and 1.72 eV, respectively. Furthermore, stacking semi-transparent [C12MIM]Cl-modified 1.77 eV WBG PSCs as top cells coupled with 1.27 eV OPV or 1.24 eV Sn-Pb PSC as bottom cells for the 4 T tandem configuration showed impressive PCE of 26.01 % and 27.44 %, respectively. This study opens a new avenue toward the sustainable fabrication of highly efficient and stable perovskite-based semitransparent and tandem solar cells.