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The small size and large trap density have seriously hindered the application of cesium copper iodine single crystals (SCs). Herein, we propose a strategy for synthesizing high-quality and large-sized CsCu2I3 SCs by gradient crystallization. The as-synthesized CsCu2I3 SCs exhibit a large length of 1.7 cm with a low trap density of 4.17 × 109 cm−3. Moreover, such CsCu2I3 SCs show excellent photoelectric response to ultraviolet (UV) irradiation, owing to their high absorption coefficient, large Stokes shift, and one-dimensional electronic structure. The measured responsivity and detectivity of the CsCu2I3 SC-based photodetectors reach the maxima of 24.58 A/W and 1.02 × 1013 Jones, respectively, under 365 nm light irradiation. Due to the outstanding UV detection performance, such photodetectors are also utilized for achieving direct UV imaging with high resolutions. [ABSTRACT FROM AUTHOR]

Flat-panel x-ray scintillators with a high spatial resolution at a low radiation dose rate are desirable for efficient imaging applications in medical diagnostics, security inspection, and nondestructive inspection. To promote the progress of x-ray imaging technologies, it is of great interest to explore transparent scintillators with reduced light scattering, high light yields, and uniform radioluminescence. Herein, we design and prepare a novel lead-free (C12H28N)2Cu2I4 metal halide featuring a high luminescent efficiency and white emission benefiting from the double self-trapped exciton mechanism, which enable to not only match the response of semiconductor-based sensors but also enhance light yields and decrease exposed doses to objects. Furthermore, transparent, and flexible scintillators with large areas of 20.25 cm2 demonstrate an outstanding scintillation performance including a high spatial resolution of 19.8 lp mm−1 and an ultralow detection limit of 28.39 nGyair s−1, which are ∼4 times higher and 194 times lower than typical values for medical imaging, respectively. This work provides not only a new route to explore promising alternatives with broadband emission but also a novel opportunity to develop flexible x-ray imaging technology. [ABSTRACT FROM AUTHOR]

Recently, mixed‐halide inorganic CsPbI3−xBrx perovskite solar cells (PSCs) have had a rapid advancement, which offers balanced efficiency, stability, tunable bandgap, and potential for indoor photovoltaic applications. Despite these advantages, significant challenges remain in the phase segregation phenomena, trap state density, and absorption range limitations. This review presents an analysis of the crystal and electronic structure and optical properties of CsPbI3−xBrx, as well as an in‐depth look at high‐quality CsPbI3−xBrx film preparation, phase segregation inhibition potential solutions, and interface engineering, highlighting the critical role of interface modification in the performance of CsPbI3−xBrx PSCs. Furthermore, how CsPbI3−xBrx PSCs can be strong candidates for indoor photovoltaics because of their adjustable bandgap that enables them to better match the absorption range and notable strength stability is discussed. Finally, the review provides perspectives to address the development bottlenecks and inspires future research prospects concerning CsPbI3−xBrx PSCs. [ABSTRACT FROM AUTHOR]

Lead‐free metal halides are considered a new generation of optoelectronic materials due to their low toxicity, superior optoelectronic properties, ease of synthesis, structural diversity, and low cost. In particular, Mn2+‐based metal halides have earned intensive attention owing to their high emission quantum efficiency, rich physical properties (e.g., triboluminescence and stimuli‐responsivity), low cost, and toxicity. Due to the different coordination environments of Mn ions, Mn2+‐based metal halides can exhibit green, red, and near‐infrared emissions. This review summarizes the recent progress of Mn2+‐based metal halides in synthesis methods, emission mechanisms, photophysical properties, and representative applications in X‐ray scintillations, white light‐emitting diodes, optical anti‐counterfeiting technologies, and fluorescent sensors. Finally, the challenges and potential research directions toward developing Mn2+‐based metal halides are also predicted. [ABSTRACT FROM AUTHOR]

Fully solution-processed oxide thin-film transistors (TFTs) have shown a great potential in future printable electronics. However, high defect densities at the dielectric/channel interface have limited the simultaneous achievement of low operating voltage and high device performance. In this Letter, we study the effects of bilayer gate dielectrics in potential performance enhancement of solution-processed indium zinc oxide (IZO) TFTs. Several single and bilayer gate dielectrics are studied in terms of their physical and electrical properties. Compared with IZO TFTs using single-layer ZrOx gate dielectrics, optimized TFTs with ZrOx/AlOx gate dielectrics show an increase in carrier mobility and current on/off ratio by a factor of 3.5 and 27, respectively. The inner mechanisms of the performance enhancement are systematically studied, showing that the significantly improved TFT performance originates from the passivation effects of AlOx, which reduce the trap/defect states at the dielectric/channel interface by approximately an order of magnitude. With a low operating voltage of 2 V, a high mobility of over 10 cm2/V s, a subthreshold swing as low as 89 mV/dec, and a high current on/off ratio of >105, the reported devices might have a great potential in future low-cost, low-power printable electronics. [ABSTRACT FROM AUTHOR]

Although low‐dimensional hybrid metal halides have emerged as promising light emitters due to their broadband emission originated from self‐trapped exciton (STE), the synthesis of lead‐free halides with high photoluminescence quantum yield remains a challenge. Herein, a series of new luminescent single crystals of antimony‐based metal halides [Na(DMSO)2]3SbBr6−xClx (x = 0, 2, 3, 4, 6) is synthesized. By optimizing the ratio of Br and Cl, [Na(DMSO)2]3SbBr3Cl3 exhibits an ultra‐broadband yellow light emission peaking at 606 nm with a full width at half‐maximum of 160 nm and a high photoluminescence quantum yield of 90.6%. Both experimental characterizations and theoretical calculations indicate that STE emission is responsible for the ultra‐broadband yellow light emission. Furthermore, blue LED chip‐pumped white light‐emitting diodes by using the yellow‐emitting [Na(DMSO)2]3SbBr3Cl3 are demonstrated, showing a correlated color temperature of 3948 K and a color rendering index of 85. Finally, a large‐size and flexible [Na(DMSO)2]3SbBr3Cl3 scintillator used for X‐ray imaging is prepared by a template assembled method, exhibiting a high spatial resolution of 15.5 lp mm−1 and a low detection limit of 285.8 nGyair s−1. This work highlights the potential of Sb‐based halides in solid‐state illumination and X‐ray imaging. [ABSTRACT FROM AUTHOR]

Due to the broadband emission induced by self‐trapped excitons (STEs), low‐dimensional hybrid lead halides are regarded as an emerging class of highly efficient light emitters. However, the toxic lead element impedes their commercial application. Here, a new air‐stable hybrid lead‐free metal halide [Na(DMSO)2]3SbBr6 with a 0D structure constituted by [SbBr6] octahedral and [Na(DMSO)2]3 units is synthesized at room temperature, which exhibits a high photoluminescence quantum yield of 60% and an ultra‐broadband yellow emission centered at 608 nm, with a full width at half‐maximum of 160 nm. First‐principles calculations and experimental studies unveil that the formation of STEs in this 0D structure contributes the broad emission. Then, warm white light‐emitting diodes (WLEDs) are proposed by combining blue LED chips with yellow [Na(DMSO)2]3SbBr6, showing a color rendering index of 85, a correlated color temperature of 3603 K. Finally, the prepared WLEDs are utilized in visible light communication (VLC) with an achieved −3 dB bandwidth of 7.2 MHz and a high transmitted data rate of 81.6 Mbps by applying orthogonal frequency division multiplexing modulation with adaptive bit loading. This research not only enriches the family of perovskite related materials, but also inspires the potential of low‐dimensional metal halide in VLC. [ABSTRACT FROM AUTHOR]

Design is the broad application of discovering new materials and technologies. Nanomaterials have been widely used in product design as a new type of material. The rapid development of nanotechnology is bound to trigger a new design revolution. Combining user needs, design concepts, and material selection, this paper discusses the relationship between user needs and nanoproducts and user needs and nanomaterials. In this paper, the design requirements and related properties of nanomaterials are put forward through the study of the hydration rate of nanomaterials after adding cement, optical microscopy, scanning electron microscopy, and morphology analysis. The effect of the addition of ultrafine materials on the dissolution of ions during cement hydration was studied by ICP technology. The experimental results in this paper show that with the development of the distance, the concentration of calcium ions gradually decreases, and the order of calcium ion concentration is No. 3 tank > No. 4 tank > No. 5 tank. The diffusion of calcium ions was enhanced after the incorporation of nanomaterials, and the diffusion ability of NT to calcium ions was stronger than that of NS group. [ABSTRACT FROM AUTHOR]

Optically pumped white-light emitting diodes (WLEDs), including down conversion phosphors and blue/ultraviolet chips have attracted considerable attention in the solid-state lighting. However, commercial WLEDs contain massive rare-earth elements, which may suffer issues of unsustainability, potential price increasing due to insufficient supply. Thus, it is important to explore rare-earth-free light emitters with a broadband emission, a high photoluminescence quantum yield (PLQY) and an excellent stability. Recently, low-dimensional hybrid metal halides have received remarkable progress in WLEDs due to their high PLQY, ultra-broadband emission and easy synthetic procedures. In this review, the synthesis methods of low-dimensional hybrid metal halides are given followed by the discussions of their photoluminescence mechanisms. After that, low-dimensional hybrid metal halides with diversity colors including blue/blue-violet, green, yellow/orange, red/near-infrared are summarized. Specially, white light-emitting diodes based on low-dimensional metal hybrid halides will be reviewed. Finally, the perspective of the evolutions and challenges, the current limitations of the materials WLEDs are discussed, aiming to point of the inspirational outlook of their future development directions. [ABSTRACT FROM AUTHOR]

Low-voltage, solution-processed oxide thin-film transistors (TFTs) have shown great potential in next-generation low-power, printable electronics. However, it is now still quite challenging to obtain low-voltage oxide TFTs with both high mobility and stability, especially for solution-processed ones. In this work, La-doped InZnO (IZO:La) channel for high performance and stable TFTs is developed using a simple solution process. The effects of La composition in IZO:La on the film and TFT performance are systematically investigated. It is confirmed that the incorporation of appropriate La could control the carrier concentration, improve the surface morphology, and passivate the oxygen-related defects, leading to a reduced trap density both at dielectric/channel interface and within the channel layer. As a result, the optimized TFTs with 1% La dopants exhibit the best overall performance, including a low operating voltage of 1 V, a high mobility of 14.5 cm2/V s, a low subthreshold swing of 109 mV/dec, a turn-on voltage close to 0 V, and negligible changes of performance under both positive and negative bias stresses. This work might support the development of all-solution-processed oxide TFT backplanes for battery-powered active-matrix displays. [ABSTRACT FROM AUTHOR]

Metal halide perovskite‐based high‐performance X‐ray scintillator is considered as one of the most favorable candidates applied in the fields of medicine, industry, and science. However, the current X‐ray scilltillators based on perovskites still suffer from the issue of poor stability, which impedes their further wide applications. Herein, a template assembled method to prepare large‐size, flexible, and stable CsPbBr3@Polymethyl methacrylate composite films in ambient conditions is developed and their detection performance is studied. The composite films can maintain 94% and 81% of the initial PL intensity after 2000 cycles bending and storing in water over 2520 h, respectively. In addition, the prepared scintillators exhibit not only a low detection limit of 40.1 nGyair s−1 and a high spatial resolution of 8.0 lp mm−1, but also an excellent tolerance against radiation (108 h). Thus, this simple but yet effective method would not doubt pave the way for further development of scintillators and might be well applicable to other metal halides. [ABSTRACT FROM AUTHOR]

The photoluminescence quantum yield (PLQY) of CsPbBr3 perovskite nanocrystals (NCs) prepared by the hot‐injection method can exceed 90%, which have attracted intensive attention for white light‐emitting diodes (WLEDs). However, the whole hot‐injection experiment requires air isolation and relatively high temperature. In addition, the poor stability of CsPbBr3 NCs impedes their applications. Here, a facile method is reported to synthesize CsPbBr3@ZrO2 NCs at room temperature in air. Owing to using ZrO2 coated CsPbBr3 NCs, the prepared CsPbBr3@ZrO2 NCs not only present a PLQY of 80% but also exhibit an enhanced stability to heat and moisture. Furthermore, WLEDs are fabricated with CsPbBr3@ZrO2 NCs and commercial red phosphors (CaAlSiN3:Eu2+) on blue LEDs chips. The fabricated WLEDs exhibit a correlated color temperature (CCT) of 4743 K and luminous efficacy as high as 64.0 Lm W–1. In addition, visible light communication with a high data rate of 33.5 Mbps is achieved using the WLEDs. This work provides a room temperature strategy to coat zirconia for CsPbBr3@ZrO2 NCs, benefiting to enhance the optical performance and stability, as well as the promotion of the great potentials in solid‐state illuminating and visible light communication applications. [ABSTRACT FROM AUTHOR]

Compared with organic–inorganic hybrid perovskites, fully inorganic perovskites show an increased stability and are therefore attracting considerable attention, especially in recent years. Such materials are not only being extensively used in applications such as solar cells and light-emitting diodes, but also show great potential as photodetectors due to their exceptional optoelectronic properties. In this review, the recent progress on emerging photodetectors based on inorganic perovskites is comprehensively summarized, focusing on the versatile compositions and morphologies of constituent materials and diverse device architectures, and covering the sensing regions from UV–visible–NIR to x-ray and even gamma-ray. A brief outlook that highlights the current challenges impeding the commercialization of inorganic perovskite-based photodetectors is also included, and possible solutions to these problems are provided. [ABSTRACT FROM AUTHOR]

The poor stability of lead‐free Cs3Cu2Cl5 nanocrystals (NCs) is the main impediment for their broad practical applications. Here, a sol‐gel reaction using tetraethoxysilane (TEOS) as the silica coating precursor to prepare Cs3Cu2Cl5@SiOx NCs is proposed. Due to the efficient passivation and robust protection of SiOx shells on the NCs surface, Cs3Cu2Cl5@SiOx NCs solution and films exhibit a high photoluminescence quantum yield of 98% and 76%, respectively, and improved stability against water and heat. Cs3Cu2Cl5@SiOx NCs are then used to fabricate warm white light‐emitting diodes (WLEDs), which show a high color‐rendering index of 94 and a proper correlated color temperature of 5049 K, and maintain an excellent thermal (265–360 K) and prolonged operating (380 h) stability. In addition, the good white light emission facilitates the application in visible light communication (VLC). The VLC light source demonstrates a −3 dB bandwidth of 420 kHz, and the achieved data rate of the VLC system reaches 2.65 Mbps using orthogonal frequency division multiplexing modulation with a bit loading. As a result, lead‐free Cs3Cu2Cl5@SiOx NCs with an efficient optical performance and an excellent stability might promote the development of stable NCs and extend the applications in optoelectronics. [ABSTRACT FROM AUTHOR]

Indium–gallium–zinc-oxide (IGZO) thin-film transistors (TFTs) gated with sputtered silicon dioxide dielectric were fabricated. Under different sputtering pressures of silicon dioxide, the device is able to produce transfer curves from clockwise hysteresis to anticlockwise hysteresis, corresponding to different operation modes and thus adding complementary performance by the same material system and device structure. In the interface trapping mode, the transistor exhibited inhibitory synaptic spiking behavior induced by positive stimuli. In the electric double-layer coupling mode, positive stimuli led to excitatory synaptic spiking behavior, while negative stimuli resulted in inhibitory synaptic spiking behavior. All the transistor and synaptic spiking behaviors are conducted within ±1 V range. Enriched functionality and ultralow operation voltage make sputtered SiO2-gated IGZO TFTs promising candidate for neuromorphic applications. [ABSTRACT FROM AUTHOR]

Due to their nontoxicity, stability, and unique optoelectronic properties, all‐inorganic lead‐free halide semiconductors with perovskite and perovskite‐like structures have successfully emerged as promising optoelectronic materials for various applications, such as solar cells, light‐emitting diodes (LEDs), photodetectors, and X‐ray detectors. To further explore their practical potentials, researchers have paid more attention in all‐inorganic lead‐free perovskite (‐like) (ILFP) single crystals. For these single crystals, the advantages of large sizes, uniform surface morphology, and few defects can facilitate their excellent performances and practical applications. Besides, compared with the low dimensional and polycrystalline ILFP materials, the ILFP single crystals feature enhanced performances, including a longer carrier diffusion length and a larger light absorption coefficient, which attract a great deal of attention. Therefore, focus is on the researching progress of ILFP single crystals and the development of their preparation methods, as well as the novel properties of ILFP single crystals. In addition, the reported applications of ILFP single crystals are proposed to highlight their practical importance. With the perspective of the evolution and challenges, the current limitations of the materials and devices are discussed, followed by an inspirational outlook on their future development directions. [ABSTRACT FROM AUTHOR]

In this letter, we report solution-processed, high-performance Indium-Zinc-Oxide (IZO) thin-film transistors (TFTs). The annealing temperature of IZO films are studied and found that devices annealed at 350 °C exhibit the best performance. With the use of a thin AlxOy layer as the gate dielectric, one-volt IZO TFTs are demonstrated, showing a high current on/off ratio of > 105, a high mobility over 10 cm2/Vs, and a low subthreshold swing (SS) of 83 mV/dec, which is fairly close to the theoretical limit of SS at 300 K. Such a high device performance is also found comparable to those deposited using vacuum-based methods. As a result, the presented devices might possess a great potential in low-cost, low-power electronics. [ABSTRACT FROM AUTHOR]

The p‐type conducting polymer poly (3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is widely utilized as the hole transport layer (HTL) for solution‐processed planar perovskite solar cells (PSCs) with a p‐i‐n structure. However, the inverted PSCs based on PEDOT:PSS HTL suffer from deficient open‐circuit voltage (VOC) and poor stability issues, because of the high electron affinity and acid nature of PEDOT:PSS. Herein, sodium benzenesulfonate (C6H5SO3Na) (SBS) is applied to modify the PEDOT:PSS (SBS–PEDOT:PSS) layer to form a smoother surface and better energy‐level alignment with the perovskite layer. In addition, the SBS–PEDOT:PSS layer with improved hole extraction capacity and suppressed charge recombination, significantly increases the grain size and crystallinity of the MA0.8FA0.2PbI3‐xClx perovskite film. Consequently, the power conversion efficiency (PCE) and VOC of the inverted PSCs are improved from 18.07% and 1.04 V to 19.41% and 1.08 V, respectively, after SBS modification. Moreover, the efficiency of the unencapsulated PSCs based on SBS–PEDOT:PSS remains above 90% after storing in ambient condition for 20 days. This research provides an accessible route to surmount the intrinsic imperfection of PEDOT:PSS and ameliorate the performance of PSCs. [ABSTRACT FROM AUTHOR]

Despite being a standard process in fabrication of organic thin‐film transistors (TFTs) to reduce interface trap density and decrease surface energy, self‐assembled monolayer (SAM) treatment of gate dielectrics is rarely used in oxide‐semiconductor‐based TFTs due to possible damage to the SAM during semiconductor deposition. Here, by studying the dependence of plasma damage to SAM on the deposition conditions of InGaZnO (IGZO) semiconductor thin films, the feasibility of enhancing the performance of oxide TFTs using octadecyltrichlorosilane (OTS)‐treated, ultra‐thin AlxOy gate dielectrics is explored. It is discovered that under optimized conditions, the TFTs can be significantly improved, showing a reduction of interface trap density by 50% and an increase of carrier mobility and current on/off ratio by a factor of 2.3 and 76, respectively. The effects on bias stress stability also show substantial improvement after the SAM interface treatment. Finally, such an optimized condition is found to also work for IGZO TFTs gated with OTS‐treated HfOx, showing an increase of mobility from 7.8 to 16 cm2 V−1 s−1 compared with the untreated devices. As a result, this simple and yet effective interface treatment method and the resulting devices may have potential applications in future low‐cost, low‐power electronics. [ABSTRACT FROM AUTHOR]