White Light Illumination Research Articles

Photo-oxidative Crack Propagation in Transition Metal Dichalcogenides.

Monolayered transition-metal dichalcogenides (TMDs) are easily exposed to air, and their crystal quality can often be degraded via oxidation, leading to poor electronic and optical device performance. The degradation becomes more severe in the presence of defects, grain boundaries, and residues. Here, we report crack propagation in pristine TMD monolayers grown by chemical vapor deposition under ambient conditions and light illumination. Under a high relative humidity (RH) of ∼60% and white light illumination, the cracks appear randomly. Photo-oxidative cracks gradually propagated along the grain boundaries of the TMD monolayers. In contrast, under low RH conditions of ∼2%, cracks were scarcely observed. Crack propagation is predominantly attributed to the accumulation of water underneath the TMD monolayers, which is preferentially absorbed by hygroscopic alkali metal-based precursor residues. Crack propagation is further accelerated by the cyclic process of photo-oxidation in a basic medium, leading to localized tensile strain. We also found that such crack propagation is prevented after the removal of alkali metals via the transfer of the sample to other substrates.

Photo-Assisted Ferroelectric Domain Control for α-In2Se3 Artificial Synapses Inspired by Spontaneous Internal Electric Fields.

α-In2Se3 semiconductor crystals realize artificial synapses by tuning in-plane and out-of-plane ferroelectricity with diverse avenues of electrical and optical pulses. While the electrically induced ferroelectricity of α-In2Se3 shows synaptic memory operation, the optically assisted synaptic plasticity in α-In2Se3 has also been preferred for polarization flipping enhancement. Here, the synaptic memory behavior of α-In2Se3 is demonstrated by applying electrical gate voltages under white light. As a result, the induced internal electric field is identified at a polarization flipped conductance channel in α-In2Se3/hexagonal boron nitride (hBN) heterostructure ferroelectric field effect transistors (FeFETs) under white light and discuss the contribution of this built-in electric field on synapse characterization. The biased dipoles in α-In2Se3 toward potentiation polarization direction by an enhanced internal built-in electric field under illumination of white light lead to improvement of linearity for long-term depression curves with proper electric spikes. Consequently, upon applying appropriate electric spikes to α-In2Se3/hBN FeFETs with illuminating white light, the recognition accuracy values significantly through the artificial learning simulation is elevated for discriminating hand-written digit number images.

The effect of light on a bioprinted co-culture system of murine rat islets and photosynthetically active microalgae

The co-cultivation of mammalian cells with microalgae is an innovative concept to overcome one major limitation in tissue engineering and regenerative medicine: shortage of oxygen. Under illumination, photosynthetically active microalgae can produce oxygen, consequently increasing the potential construct dimension. In such co-cultures, mammalian cells are exposed to light, which does not reflect their natural conditions and can negatively influence their viability and functionality.In this study, 3D extrusion bioprinted pancreatic murine Islets of Langerhans should be co-cultivated with the bioprinted green microalgae species Scenedesmus sp. to improve the oxygen supply of the Islets in a potential insulin-producing implant. After defining the microalgae partner and a suitable co-culture medium that supported the functionality of both cell types, the focus was put on the effects of long-term red, blue and white light illumination on this system. First, the direct influence of light of different wavelengths on both microalgae and different mammalian cell types was investigated to find an ideal illumination regime, followed by an investigation into the influence of light on the culture medium. It was found that long-term exposure to blue or white light is detrimental to mammalian cells itself as well as the medium, while long-wave light has no effect on the function of mammalian cells.

Photovoltaic and mechanical properties of boron carbide films prepared by magnetron sputtering

In this study, amorphous boron carbide (B x C) and hydrogenated amorphous B x C (B x C:H) films were deposited via magnetron sputtering to investigate the effects of hydrogen on the film properties. The critical load decreased with increasing H2 flow ratio, probably due to an increase in the internal stress. In addition, the optical bandgap increased with the H2 flow ratio increased. The bandgap was controlled by the chemical bonding of carbon atoms and the chemical composition of films. The resistivity of the films increased with the H2 flow ratio and bandgap energy. The current–voltage characteristics of B x C(:H)/n-type Si heterojunctions under white light illumination showed that the short-circuit current density and open-circuit voltage were higher than the previously reported values. Results revealed that the introduction of hydrogen during deposition reduced the short-circuit current density, fill factor, and conversion efficiency, whereas the open-circuit voltage remained almost unchanged.

Is Doping of Spiro-OMeTAD a Requirement for Efficient and Stable Perovskite Indoor Photovoltaics?

Lead halide perovskite (LHP) photovoltaics deliver high voltages even under low-light illumination intensities, thus emerging as a promising indoor photovoltaic (IPV) technology. The doping of the 2,2′,7,7′-tetrakis( N , N -di-p-methoxyphenylamino)-9,9′-spirobifluorene (Spiro-OMeTAD) hole-transport layer (HTL) is the most widely adopted strategy for high-performance LHP-based solar cells. Yet, the importance of Spiro-OMeTAD doping is unclear in the context of indoor photovoltaics. In this report, we examine the role of the traditional Spiro-OMeTAD dopants on the performance of LHP-based IPVs. The diminished influence of the series resistance under indoor lighting leads to an improved fill factor of IPV devices even in the absence of the dopants. The pristine (dopant-free) Spiro-OMeTAD HTL ensures a power conversion efficiency (PCE) as high as 25.6% at 1,000 lux, comparable to that of 29.7% in the presence of the dopants, and an open-circuit voltage of ≈0.65 V even at 50 lux. The undoped Spiro-OMeTAD-containing devices exhibit a ≈25% gain in their PCE under long-term and continuous white light illumination at the maximum power point, thus leading to the PCE values on par or higher than those of employing doped Spiro-OMeTAD. Furthermore, the current–voltage hysteresis behavior of the undoped Spiro-OMeTAD-containing devices remains unchanged in the 100 to 1,000 lux light-intensity range, unlike the case of doped Spiro-OMeTAD HTL. Our findings suggest that the dopants in Spiro-OMeTAD HTL are not required to achieve efficient, stable, and reliable IPV performance, and the optimization of the various device constituents for outdoor solar cell applications may not necessarily lead to the best performance for indoor photovoltaics.

Illumination Effects on Bacteriorhodopsin Accumulation in Archaeon Halobacterium Halobium

Highlights Effects of varying illumination conditions, including light intensity, light color, and illumination pattern on archaeon Halobacterium halobium growth and bacteriorhodopsin (BR) accumulation were first evaluated. LED green light was much more energy-efficient than the red and blue lights in this research. If energy consumption was not a concern, LED blue and red lights (or their combinations) were more effective for cell growth and BR accumulation, respectively, with a similar light intensity. Abstract. This study was to understand the effect of LED light intensity, color, and illumination pattern on the growth of and bacteriorhodopsin (BR) accumulation in archaeon Halobacterium halobium. Experimental results showed that archaeon growth and BR content increased with increasing white light intensity. Green and white LED lights were found to be the most effective for archaeon growth and BR accumulation; here, effectiveness is defined based on photons shined on the bioreactor. The 12-h light/12-h dark cycle illumination pattern resulted in longer lag phase but achieved higher final cell growth and BR accumulation than continuous white light or an instant flash of light/dark illumination. The fade pattern that had smooth transitioning among green, blue, and red lights was better than the jump pattern without transitioning. The highest cell dry weight and BR content of H. halobium were 1.84 g l-1 and 11.76 mg l-1, respectively, under 29.85 µmol/m2s LED white light illumination. The green LED light of 1.39 µmol/m2s had the highest energy-specific conversion effectiveness and saved energy consumption by 84 and 87% per cell biomass and BR dry weight, respectively, compared to the worst case of LED white light of 29.85 µmol/m2s. Keywords: Archaeon, Bacteriorhodopsin, Halobacterium halobium, Illumination pattern, LED light, Light color.

An efficient blue-violet phosphor: an advanced material designed for high-quality full-spectrum lighting.

A highly efficient phosphor with exceptional luminescence properties is crucial for achieving high-quality solid-state white-light illumination. Here, this paper presents a groundbreaking discovery, an innovative blue-violet emitting Ba1.31Sr3.69(BO3)3Cl:Ce3+ (BSBCl:Ce3+) phosphor designed with remarkable thermal stability and quantum efficiency for full spectrum white light-emitting diodes (WLEDs). By employing a high-temperature solid-phase method, we synthesized various BSBCl:xCe3+ phosphors with different Ce3+ doping concentrations. Remarkably, BSBCl:0.03Ce3+ displays a broad excitation band from 250 nm to 400 nm, rendering it compatible with commercial near-ultraviolet (UV) LED chips. Under 330 nm excitation, this phosphor emits blue light with an astonishing 88.2% internal quantum efficiency (IQE) and an impressive 60.9% external quantum efficiency (EQE). Notably, when employed in the temperature range of 298-473 K, the synthesized BSBCl:0.03Ce3+ phosphor exhibits exceptional color stability and thermal stability (I423 K/I298 K = 83%). Utilizing BSBCl:0.03Ce3+ as the blue-violet emitting component in the fabrication of WLED devices has demonstrated significant advancements in the color rendering index. These findings underscore the potential of BSBCl:Ce3+ phosphors for a wide range of applications in health-oriented indoor illumination.

Synthesis and luminescent properties of a new cyan Ca18Li6-3xYx(PO4)14:0.1Eu phosphors and PVA-based composite films for multifunctional applications

The development of light-emitting materials capable of efficiently emitting broad-band cyan light is of paramount importance in the quest for full-spectrum white light illumination. In this study, a series of new Ca18Li6-3xYx(PO4)14:0.1Eu phosphors with adjustable luminescent properties were synthesized through a high-temperature solid-phase method, and the investigation encompassed an analysis of their crystal structures, luminescence characteristics, and thermal stability. Meanwhile, the optimal doping concentration of Y3+ ions in the Ca18Li6-3xYx(PO4)14:0.1Eu host was identified to be x = 0.3, achieved through the modulation of the substitution ratio of Y3+ to Ca2+ to regulate the occupancy of Eu2+ at different sites. The resulted in the generation of asymmetric cyan color emission spectra (FWHM = 47 nm) with broad-band emission spanning the 425–550 nm range under 378 nm excitation. In addition, the application of the optimized cyan-emitting phosphor Ca18Li5.1Y0.3(PO4)14:0.1Eu in w-LED devices led to a significant enhancement in the CRI from 89.1 to 91.2, accompanied by a reduction in the correlated color temperature from 4896 K to 4566 K. These results highlight the potential utility of the cyan-emitting Ca18Li5.1Y0.3(PO4)14:0.1Eu phosphors in full-visible-spectrum solid-state illumination. Notably, the optimized cyan-emitting phosphor Ca18Li5.1Y0.3(PO4)14:0.1Eu was synthesized in conjunction with soluble polyvinyl alcohol (PVA) to yield a transparent anti-counterfeiting ink. The resulting film exhibited exceptional flexibility, foldability, and superior thermal and optical properties. Moreover, the emission band of this phosphor, situated in the 425 nm–550 nm spectral region, represents a crucial blue light source beneficial for plant growth. In summary, the highly efficient phosphor Ca18Li5.1Y0.3(PO4)14:0.1Eu is a promising material with multifunctional luminescent potential for general illumination, anti-counterfeiting, and light-converting agricultural films.

3D-printed multilayer structures for high-numerical aperture achromatic metalenses.

Flat optics consisting of nanostructures of high-refractive index materials produce lenses with thin form factors that tend to operate only at specific wavelengths. Recent attempts to achieve achromatic lenses uncover a trade-off between the numerical aperture (NA) and bandwidth, which limits performance. Here, we propose a new approach to design high-NA, broadband, and polarization-insensitive multilayer achromatic metalenses (MAMs). We combine topology optimization and full-wave simulations to inversely design MAMs and fabricate the structures in low-refractive index materials by two-photon polymerization lithography. MAMs measuring 20 μm in diameter operating in the visible range of 400 to 800 nm with 0.5 and 0.7 NA were achieved with efficiencies of up to 42%. We demonstrate broadband imaging performance of the fabricated MAM under white light and RGB narrowband illuminations. These results highlight the potential of the 3D-printed multilayer structures for realizing broadband and multifunctional meta-devices with inverse design.

Diffraction patterns of optical discs under the far-field condition

When optical discs are illuminated, bright-colored lines can often be observed on the surface of them. Starting from the oblique incident grating diffraction model, this paper analyzes the physical mechanism behind the appearance of these colored lines and provides the coordinate expression of the location of the colored lines on the optical disc under the far-field condition. The wavelength distribution of the colored lines on the optical disc under white light illumination is also given by the wave vector relationship of the diffraction process. To verify the theoretical analysis results, an experimental apparatus was designed and constructed to measure the position and color of the colored lines. The experimental data, analyzed through Gaussian process regression and direct comparison, demonstrates a good consistency with the theoretical analysis results.

Modulation of optical properties for lighting applications based on CsPbBr3−xIx quantum dot doped glasses

All inorganic halide perovskite quantum dots (PQDs) exhibit excellent optical properties and have been intensively exploited for diverse applications in the field of optoelectronics. However, their inherent frangibility remains an enormous challenge for both practical applications and scientific research. The recently emerged oxide glasses doped with such PQDs exhibit high stability against degradation, which is promising for practical applications. Here, borosilicate glasses doped with CsPbBr3−xIx PQDs were prepared by the traditional melt-quenching and subsequent annealing process. By introducing alkaline metal oxides as the glass network modifier to adjust glass network structure, the optical properties of the precipitated PQDs are significantly enhanced. The photoluminescence (PL) intensity and photoluminescence quantum yield (PLQY) can be enhanced by up to 200 % and 29 % for the sample fabricated under optimal conditions, respectively. By leveraging the strong PL of the developed PQD-doped glasses, we demonstrate the fabrication of phosphor-converted light emitting devices for white light illumination and plant illumination based on samples with PL peak wavelengths at approximately 570 nm and 650 nm, respectively.

Fast Near-Infrared Photodetectors Based on Nontoxic and Solution-Processable AgBiS2.

Solution-processable near-infrared (NIR) photodetectors are urgently needed for a wide range of next-generation electronics, including sensors, optical communications and bioimaging. However, it is rare to find photodetectors with >300kHz cut-off frequencies, especially in the NIR region, and many of the emerging inorganic materials explored are comprised of toxic elements, such as lead. Herein, solution-processed AgBiS2 photodetectors with high cut-off frequencies under both white light (>1MHz) and NIR (approaching 500kHz) illumination are developed. These high cut-off frequencies are due to the short transit distances of charge-carriers in the ultrathin photoactive layer of AgBiS2 photodetectors, which arise from the strong light absorption of this material, such that film thicknesses well below 120nm are sufficient to absorb >65% of NIR to visible light. It is also revealed that ion migration plays a critical role in the photo-response speed of these devices, and its detrimental effects can be mitigated by finely tuning the thickness of the photoactive layer, which is important for achieving low dark current densities as well. These outstanding characteristics enable the realization of air-stable, real-time heartbeat sensors based on NIR AgBiS2 photodetectors, which strongly motivates their future integration in high-throughput systems.

Biocompatible optical physically unclonable function hydrogel microparticles for on-dose authentication

On-dose authentication (ODA) enhances security by incorporating customized molecular or micro-tags into each pill, preventing counterfeit products in genuine packages. ODA's security relies on tag non-replication and non-reverse engineering. Combining ODA with graphical Physical Unclonable Functions (PUF) promises maximum security. PUF uses intrinsic micro or nanoscale randomness as a unique ‘fingerprint’. However, current graphical PUFs have limitations like specific illumination requirements and the use of toxic materials, restricting their use in pharmaceuticals.In this study, we propose a novel approach called on-dose PUF. This method involves embedding microspheres randomly within micro biocompatible hydrogel particles. We showcase two distinct types of such on-dose PUFs. The first type utilizes randomly distributed superparamagnetic colloids (SPC) of identical diameters, while the second type utilizes vortexed sunflower oil drops of various diameters. The diameter and coordinates of the microspheres serve as input for generating cryptographic keys. A universal circle identification and binning program is used for extracting this information. One advantage of this approach is that it enables imaging using white light illumination and low-magnification microscopy, as color and signal intensity information are not crucial. This method enables patients to verify their medication by using their mobile phones from home.To assess the performance of the proposed on-dose PUF, we conducted canonical investigations on the single-diameter system. This system can only generate one layer of cryptographic keys, making it potentially more vulnerable than the multiple-diameter system. However, the single-diameter system successfully passed NIST Statistical tests and exhibited sufficient randomness, ideal bit uniformity, Hamming distance, and device uniqueness. Furthermore, we found that the encoding capacity of the single-diameter system was 9.2×1018, providing ample labeling potential.

Defect engineering of RF sputtered Mg doped ZnO thin film for efficient photodetector application

Mg0.1Zn0.9O thin films were deposited using RF magnetron sputtering system on p-Si substrate, which were then annealed at various temperatures in air. The experiments showed that the crystallinity and surface roughness of the Mg0.1Zn0.9O films increased with the annealing temperature, meanwhile red shift was observed in the optical bandgap. The field emission scanning electron microscope (FESEM) analysis revealed that the surface morphology becomes more homogeneous with annealing temperature. A near band emission (NBE) and three deep level emission (DLE) (violet, blue and weak green emission) were observed from PL analysis for all the samples (as-deposited, 100 °C, 300 °C, 500 °C, and 700 °C). A red shift in the NBE (from 352 nm to 371 nm) and also disappearance of DLE at around 540 nm was observed with increase in annealing temperature. The MgZnO/p-Si device (500 °C) exhibits great photosensitivity (24-fold enhancement) as compare to as-deposited device because the thin film (TF) has high surface to volume ratio and the massive amount of photogenerated carriers. In addition, MgZnO/p-Si (500 °C) demonstrated quick device response with a rise time of 0.78 s and a fall time of 0.26 s under white light illumination.

Overlapping speckle correlation algorithm for high-resolution imaging and tracking of objects in unknown scattering media

Optical imaging in scattering media is important to many fields but remains challenging. Recent methods have focused on imaging through thin scattering layers or thicker scattering media with prior knowledge of the sample, but this still limits practical applications. Here, we report an imaging method named ‘speckle kinetography’ that enables high-resolution imaging in unknown scattering media with thicknesses up to about 6 transport mean free paths. Speckle kinetography non-invasively records a series of incoherent speckle images accompanied by object motion and the inherently retained object information is extracted through an overlapping speckle correlation algorithm to construct the object’s autocorrelation for imaging. Under single-colour light-emitting diode, white light, and fluorescence illumination, we experimentally demonstrate 1 μm resolution imaging and tracking of objects moving in scattering samples, while reducing the requirements for prior knowledge. We anticipate this method will enable imaging in currently inaccessible scenarios.

Luminescence and thermal stability of CaLu2-x-yMeyMg2Si3O12:xCe3+ (Me = Sr, Ba) fluorescent materials

White light solid-state lighting applications still face significant challenges due to insufficient efficient and stable red light emitting materials. Therefore, a series of orange-red fluorescent materials, CaLu2-xMg2Si3O12:xCe3+ (CLMS:xCe3+; x = 0.02, 0.04, 0.06, 0.08, 0.10, 0.12) were prepared in this paper. Luminescence spectra testing revealed that the optimal concentration of Ce3+ ions in the crystal lattice is x = 0.04. At 460 nm excitation, the emission wavelength is approximately 592 nm. To enhance the thermal stability and luminescence performance of CLMS:Ce3+, the CaLu1.96-yMeyMg2Si3O12:0.04Ce3+ (Me = Sr, Ba; y = 0, 0.02, 0.05, 0.10, 0.15, 0.20) fluorescent materials were successfully prepared. It was found that phosphor's fluorescence intensity was enhanced after the introduction of Sr2+ or Ba2+ ions. Meanwhile, the phosphors were tested for thermal stability, and the emission intensities of CLMS:0.04Ce3+, CLMS:0.04Ce3+,0.10Sr2+, and CLMS:0.04Ce3+,0.05Ba2+ phosphors decreased to 77.60%, 85.53%, and 87.63% at 423 K, respectively. This proves that Sr2+ and Ba2+ ions have a positive effect on the thermal stability performance of CLMS:0.04Ce3+ phosphor. Testing of the w-LED devices, the CCT was reduced. The CRI was improved to 80.4 and 81.6 and luminescence efficiency was improved to 107.71 lm/W and 115.04 lm/W after Sr2+ or Ba2+ ions were introduced. In summary, this study demonstrates that CaLu2-x-yMeyMg2Si3O12:xCe3+ (Me = Sr, Ba) is an auspicious fluorescent material with high thermal stability, which is potentially informative for the field of white-light illumination.

Aggregation‐Induced Emission Photosensitizer‐Armored Magnetic Nanoparticles for Sepsis Treatment: Combating Multidrug‐Resistant Bacteria and Alleviating Inflammation

AbstractSepsis, a life‐threatening condition stemming from an uncontrolled host immune response to bacterial infections, continues to impose a significant global burden with high morbidity and mortality. Addressing the challenges posed by antimicrobial resistance and uncontrollable inflammation remains a challenge in sepsis treatment. Moreover, traditional antibacterial materials have low bacterial trapping efficiency and inevitable prolonged circulation within the bloodstream, resulting in suboptimal antibacterial effects, metabolic complications, and undesirable side effects. In this study, an innovative solution is introduced through the development of Fe3O4@SH@TBTCP‐PMB, an aggregation‐induced emission (AIE) photosensitizer (PS)‐armored magnetic nanoparticles (NPs). It has high reactive oxygen species (ROS) generation efficiency and an exceptional ability to capture Gram‐positive bacteria with over 80% enrichment efficiency within just 1 h, even at low bacterial concentrations. Under white light illumination, 100 µg mL−1 of Fe3O4@SH@TBTCP‐PMB effectively eliminated more than 99.9% of methicillin‐resistant Staphylococcus aureus (MRSA). Furthermore, its magnetic separation properties efficiently prevent systemic blood circulation and associated side effects. Most importantly, Fe3O4@SH@TBTCP‐PMB demonstrates superior anti‐inflammatory effects by regulating cytokines, reducing adhesion molecule expression, and managing oxidative stress levels. This multifunctional approach significantly enhances sepsis survival rates, offering a promising strategy for combating multidrug‐resistant (MDR) bacterial infections in sepsis patients while addressing inflammation‐related complications.

Tunable luminescence spectra of solid solution phosphors Gd3(Sb1-yTay)O7:Bi3+ for ultrahigh color rendering index full-spectrum white light-emitting diodes

The development of efficient luminescent materials that can compensate for the cyan gap is essential for actualizing high-quality full-spectrum white light-emitting diode (wLED) illumination. In this paper, a novel blue-emitting phosphor Gd3SbO7:Bi3+ was synthesized with an emission center located at 449 nm. Based on the cation substitution strategy, the cyan-emitting Gd3TaO7:Bi3+ phosphor is developed by completely replacing Sb5+ ions with Ta5+ ions in Gd3SbO7:Bi3+. Compared with Gd3SbO7:Bi3+, Gd3TaO7:Bi3+ also has an orthorhombic phase with the space group Ccmm, except that its emission wavelength is red-shifted by 45 nm from 449 to 494 nm, and the luminescence color is changed from blue to cyan. Thermal stability measurements demonstrate the negative effect of increasing Ta5+ doping concentration on the thermal stability of Gd3SbO7:Bi3+ phosphors. And a full-spectrum wLED device was fabricated using Gd3SbO7:Bi3+, Gd3TaO7:Bi3+, commercial (Sr, Ba)2SiO4:Eu2+ and CaAlSiN3:Eu2+ phosphors, with an impressive color rendering index (Ra = 94.7, R9 = 93) and suitable correlated color temperature (5832 K). The research results demonstrate the important role of Gd3TaO7:Bi3+ phosphors in compensating the cyan gap, and also provide new insights into the application of cyan phosphors in full-spectrum white light illumination.

Tools for classification of growing/non-growing bacterial colonies using laser speckle imaging.

Prior research has indicated the feasibility of assessing growth-associated activity in bacterial colonies through the application of laser speckle imaging techniques. A subpixel correlation method was employed to identify variations in sequential laser speckle images, thereby facilitating the visualization of specific zones indicative of microbial growth within the colony. Such differentiation between active (growing) and inactive (non-growing) bacterial colonies holds considerable implications for medical applications, like bacterial response to certain drugs or antibiotics. The present study substantiates the capability of laser speckle imaging to categorize bacterial colonies as growing or non-growing, a parameter which nonvisible in colonies when observed under white light illumination.

CsPbBr3 Nanocrystals as Efficient Photocatalysts for Dehydrohalogenation: Toward Environmentally Friendly Trichloroethylene Synthesis.

The demand for a benign alternative to energy-intensive industrial chemical transformations is critical. Lead halide perovskites have emerged as promising candidates due to their unique optoelectronic properties, including high absorption coefficients in the visible region, tunable band gaps, and long charge carrier-diffusion lengths. In this study, we present a model reaction to showcase the photocatalytic utility of perovskite nanocrystals (NCs). Specifically, we demonstrate the synthesis of trichloroethylene (TCEt) from 1,1,2,2-tetrachloroethane (TCE) using CsPbBr3 NCs under white light illumination. The band-edge positions of the NCs and the redox potential of TCE enable efficient electron transfer for C-Cl bond activation. Furthermore, while ensuring operational stability, CsPbBr3 NCs undergo light-controlled modification, leading to the formation of mixed-halide perovskite (CsPbBrxCl3-x) NCs during the reaction. This procedure yields a mixed-halide perovskite that maintains stability while containing the desired halide content. Additionally, the reaction produces HBr as a byproduct, serving as a self-cleaning technique to eliminate excess Br- ions from the solution. Ultimately, we achieve nearly 100% conversion of CsPbBr3 to pure CsPbCl3 NCs, with a full width at half-maximum of approximately 11.2 nm. Our clean and efficient approach to synthesizing TCEt using perovskite NCs provides interesting insights into violet light-emitting diode (LED) fabrication and color patterning. This study highlights the promising potential of perovskite materials for sustainable chemical transformations and optoelectronic applications.