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Quantum dot enhancement film (QDEF) working in tandem with a blue light-emitting-diode (LED) back-light-unit (BLU) has been recently used in liquid crystal display (LCD) to minimize the cross talks between the polarized emitting B-, G-, and R-light. However, they still exhibit a fundamental and considerable emitting-light-power loss from QDEF because of the light absorption loss in resin and transparent films of QDEF. In this work, we propose and demonstrate the superiority of the LCD using blue-(B-), green-(G-), and red-(R-) perovskite-quantum-dot (PrQD) functional CFs coupled with a blue LED BLU. This LCD using PrQD functional CFs and a blue LED BLU features cross-talk free spectra of polarized emitting B-, G-, and R-light, maximizing the LCD color gamut and exhibiting a world record performance of over 102.7% (137%) of Rec.2020 standard (NTSC standard). Theoretically, such an improvement in color gamut would facilitate unlimited scaling-down of the pixel leading to super ultra-high resolution LCD.

reflection, scattering, and thermalization losses, which limit conversion efficiency. [10] These losses are mostly caused by the energy difference between the incident UV photons (>3.2 eV) and bandgap of PV cells (1.0-1.6 eV). [11] If these photons are not surface reflected, their excess energy will be adversely dissipated in cells as heat via the nonradiative relaxation of the photoexcited electronhole pairs leading to further limitations and faster degradation of PV cells. [12] One of the most promising approaches to overcome these limitations is to implement the surfaces of PV devices with an energydownshift quantum-dot (EDS-QD) layer to harvest the wasted UV photons and reemit them at visible wavelengths absorbed more efficiently by PV cells. [13] Moreover, EDS-QDs have been well demonstrated as an effective layer that boosts the energy density, then the usage active area of PV cells could be reduced by the same percentage of enhancement in PV efficiency for a defined amount of power. Due to the enhanced efficiency along with the low cost of preparing EDS-QDs, the cost of PV electricity generation could be effectively minimized. [1d,14] For the abovementioned reasons, the concept of the EDS-QD layer was proposed for solar energy conversion for both increasing the efficiency and lessening the cost.Motivated by these purposes and attracted by their excellent optical properties, Cd-based core/shell QDs, such as CdSe/ CdS, [13c,15] CdSe/CdZnS, [16] CdSe/ZnS, [11b] and Cd 0.5 Zn 0.5 S/ ZnS [13b,17] QDs have been used recently as EDS layers. However, the relying on the Cd-based QDs in commercial solar cells has been limited due to two main reasons; the toxicity of Cd metal ions [18] and the self-reabsorption losses within their QDs. [13a] For the latter, Mn-doped Cd 0.5 Zn 0.5 S/ZnS QDs have been introduced more recently [13a,14a] as an excellent EDS-QD layer having free-self-reabsorption with large Stokes shift, yet with environmentally hazardous Cd material. [19] As a result, the quest for nontoxic high photoluminescence-quantum yield (PLQY) and the zero-self-reabsorption EDS-QD layer is a priority for their commercial applications.Alternatively, chalcogenide CIGS is one of the most promising semiconductor materials for EDS-QD layers due to its beneficial properties of large absorption coefficient (10 5 cm −1 ), [20] eco-friendly nature, [19,21] long-term stability, [22] It is presented for the first time nontoxic CuGaS 2 /ZnS quantum dots (QDs) with free-self-reabsorption losses and large Stokes shift (>190 nm) synthesized on an industrially gram-scale as an alternative for Cd-based energydownshift (EDS)-QD layers. The QDs exhibit a typical EDS that absorbs only UV light (<407 nm) and emits the whole range of visible light (400-800 nm) with a high photoluminescence-quantum yield of ≈76%. The straightforward application of these EDS-QDs on the front surface of a monocrystalline p-type silicon solar cell significantly enhances the short-circuit current density by ≈1.64 mA cm −2 (+4.20%); thereby, improving ...

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advantages of high catalytic activity, good stability, low cost, and other unique properties of nanomaterials. So far, a variety of nanoscale materials, such as fullerene derivatives, [5,6] gold nanoparticles, [7,8] rare earth nanoparticles, [9] and ferromagnetic nanoparticles, [10] have been discovered to possess unique enzyme-mimic catalytic activities. These nanozymes have already found wide applications in numerous fields, including biosensing, disease therapy, detoxification, and pollutant removal. [3] Perovskite nanocrystals (NCs) have emerged as potential candidates for the next-generation lighting systems, because of their extraordinary physiochemical properties, such as, simple synthesis, high fluorescence quantum yield, narrow emission bandwidth, and wide and tunable emission covering the full visible range. [11][12][13] In consideration of their unique advantages and huge success in optoelectronics, [14,15] one may envision perovskite NCs would also hold great potential for biological applications akin to their quantum dots counterparts. However, the application of perovskite NCs in biological fields is largely lagged, because they are limited by some longstanding concerns, including extremely low stability in aqueous CsPbX 3 perovskite nanocrystals (NCs), with excellent optical properties, have drawn considerable attention in recent years. However, they also suffer from inherent vulnerability and hydrolysis, causing the new understanding or new applications to be difficultly explored. Herein, for the first time, it is discovered that the phospholipid membrane (PM)-coated CsPbX 3 NCs have intrinsic biocatalytic activity. Different from other peroxidase-like nanozymes relying on extra chromogenic reagents, the PM-CsPbX 3 NCs can be used as a self-reporting nanoprobe, allowing an "add-to-answer" detection model. Notably, the fluorescence of PM-CsPbX 3 NCs can be rapidly quenched by adding H 2 O 2 and then be restored by removing excess H 2 O 2 . Initiated from this unexpected observation, the PM-CsPbX 3 NCs can be explored to prepare multi-color bioinks and metabolite-responsive paper analytical devices, demonstrating the great potential of CsPbX 3 NCs in bioanalysis. This is the first report on the discovery of nanozyme-like property of all-inorganic CsPbX 3 perovskite NCs, which adds another piece to the nanozyme puzzle and opens new avenues for in vitro disease diagnostics.The ORCID identification number(s) for the author(s) of this article can be found under

Electrochemical biosensing relies on electron transport on the electrode surface. However, the limited functional area of the two-dimensional electrode prevents the qualitative breakthrough in the efficiency of electron transfer. Here, a threedimensional electron transporter was constructed to improve the efficiency of electron transfer by using an interface-immobilized DNA hydrogel. A three-dimensional pure DNA hydrogel is constructed and used as a scaffold for electron transfer. Then, an electron mediator is embedded in the DNA hydrogel through intercalative binding, and DNAzyme with intrinsic peroxidase-like activity is introduced at the node of the hydrogel scaffold to fabricate an electrochemical biosensor. The conduction of the electron mediator in the scaffold enables the acquisition of long-distance DNAzyme catalytic signals, thereby overcoming the limitation of two-dimensional electrodes. This three-dimensional electron transporter is significant for enriching the toolbox of electrochemical biosensing and can provide potential support for the development of highly sensitive biosensors.

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