Full-spectrum Light Research Articles

Photocatalytic CO2 reduction holds great potential for sustainable solar fuel production, yet its practical application is often limited by inefficient charge separation and poor product selectivity. The photothermal effect presents a viable strategy to address these challenges by reducing activation energies and accelerating reaction kinetics. In this work, we report a rationally designed CN-B/Ti3C2 heterojunction that effectively leverages photothermal promotion for enhanced CO2 reduction. The black carbon nitride (CN-B) framework, synthesized via a one-step calcination of urea and Phloxine B, exhibits outstanding photothermal conversion, reaching 131.4 °C under 300 mW cm−2 illumination, which facilitates CO2 adsorption and charge separation. Coupled with Ti3C2 MXene, the optimized composite (3:1) achieves remarkable CO and CH4 production rates of 80.21 and 35.13 μmol g−1 h−1, respectively, without any cocatalyst—representing a 2.9-fold and 8.8-fold enhancement over CN-B and g-C3N4 in CO yield. Mechanistic studies reveal that the improved performance stems from synergistic effects: a built-in electric field prolongs charge carrier lifetime (3.15 ns) and reduces interfacial resistance, while localized heating under full-spectrum light further promotes CO2 activation. In situ Fourier transform infrared (FTIR) spectroscopy confirms the accelerated formation of key intermediates (*COOH and *CO). The catalyst also maintains excellent stability over 24 h. This study demonstrates the promise of combining photothermal effects with heterojunction engineering for efficient and durable CO2 photoreduction.

White light-emitting diodes (LEDs), the most commonly used artificial light source in indoor farming systems, require spectrum optimization for crop-specific responses. This study evaluated the effects of wavelength-specific blue and green modifications on tomato growth, productivity, and fruit quality. Treatments included normal white LEDs (NWL), two wavelength-specific white LEDs (SWL1 and SWL2), and a red + blue LED combination as control. NWL represented a broad-spectrum baseline, SWL1 was enriched in red and long-green wavelengths, SWL2 emphasized blue and short-green wavelengths, and the red+blue combination served as a conventional control. Both SWL treatments enhanced biomass, leaf area, and fruit yield relative to the control. In particular, SWL1 increased fruit number (+38%), total yield (+48%), °Brix (+16%), and reducing sugar (+30%) relative to the control. SWL2 improved fruit number and yield by 23% and 26%, respectively, but did not enhance °Brix or reducing sugar. In addition, fruits from SWL1 showed higher antioxidant capacity, consistent with elevated lycopene accumulation. Yield and sugar gains under SWL1 suggest that spectral tuning toward long-green wavelengths promotes assimilate partitioning into fruit. Moreover, SWL1 demonstrated superior light use efficiency and energy use efficiency. These findings suggest that tailoring the spectral peaks of white LEDs, particularly in the blue and green regions, can enhance tomato productivity and fruit quality. Wavelength-specific full-spectrum lighting therefore represents a promising strategy for high-efficiency tomato cultivation and provides a practical lighting solution to reduce energy costs while improving crop value in indoor farming systems.

Synthesis of PPy-BiVO4-Cu2+ heterojunction and its visible-light-driven photocatalytic degradation of 2,4-dichlorophenol.

Machine learning-assisted magnetic nanomotors for the identification and degradation of organic pollutants.

Insufficient harvesting of visible photons, limited adsorption, and fast recombination of photogenerated electron-hole pairs restrict the application of graphitic carbon nitride (g-C3N4). Here, we propose a straightforward solid-phase synthesis method for fabricating 2D/2D graphitic carbon nitride/reduced graphene oxide (SCN/GR) hybrid photocatalysts. The synthesis process involves the thermal condensation of three precursors: dicyandiamide (as the g-C3N4 source), NH4Cl (as a pore-forming agent), and graphene oxide (GO, which is in situ reduced to rGO during thermal treatment). The incorporation of reduced graphene oxide (rGO) into the g-C3N4 matrix not only narrows the bandgap of the material but also expedites the separation of photogenerated carriers. The photocatalytic activity of the SCN/GR hybrid was systematically evaluated by degrading ciprofloxacin in aqueous solution under different light conditions. The results demonstrated remarkable degradation efficiency: 72% removal within 1 h under full-spectrum light, 81% under UV light, and 52% under visible light. Notably, the introduction of rGO significantly improved the visible light absorption capacity of g-C3N4. Additionally, SCN/GR exhibits exceptional cyclic stability, maintaining its structural integrity and photocatalytic properties unchanged across five successive degradation cycles. This study offers a simple yet effective pathway to synthesize 2D/2D composite photocatalysts, which hold significant promise for practical applications in water treatment processes.

Photocatalytic oxidation of methane to methanol oxygenates (CH3OH and CH3OOH) under mild conditions represents a promising approach for methane valorization, yet achieving both high efficiency and high selectivity remains a significant challenge. Herein, a defect-engineered spatial coupling strategy is devised to construct a heterojunction photocatalyst (Def-CuCN/NU) by integrating copper single atoms (Cu SA) anchored on polymeric carbon nitride (CN) into the defective NH2-UiO-66 (Def-NU). The defective MOFs with porous structure and abundant active sites serve as microreactors that enhance methane adsorption and promote methanol desorption, thus promoting the reaction and minimizing the contact of methanol with ·OH radicals and effectively suppressing overoxidation. Additionally, the heterojunction formed between CuCN and Def-NU accelerates charge separation and transport, which renders efficient photocatalytic conversion of methane to methanol oxygenates. Notably, the Def-CuCN/NU catalyst affords a high production rate of 1718µmolg-1h-1 for methanol oxygenates under full-spectrum light irradiation at a remarkable selectivity of 96.5%. This study presents the first demonstration of employing defect-engineered MOFs-based heterojunction photocatalysts for the regulation of the reaction pathway to enable highly selective photocatalytic oxidation of CH4.

This paper pilots a method for the assessment of non-visual lighting effects based upon annual full-spectrum lighting calculations termed an ipRGC-influenced/Non-Visual Spectral Occupant Model (iNSOM). iNSOM calculates annualized melanopic irradiance, described in our previous paper, and derives seasonal and time-of-day metrics based on a collection of photobiological models from Postnova et al ., Abeysuria et al . and Tekieh et al . to predict circadian dynamics, alertness and melatonin levels due to light exposure. Quantitative outputs of these metrics and novel spatial visualizations are then used to evaluate lighting design based on the predicted intrinsically photosensitive retinal ganglion cell (ipRGC)-influenced effect on occupants. The model is demonstrated using an example hospital ward model and tested under three daylight, electric light and screen device operational scenarios and two types of sleep quality. A comparative analysis between iNSOM and existing ipRGC-influenced lighting design metrics and standards demonstrates how ipRGC-influenced alertness and health metrics differ from existing saturation-based ipRGC-influenced lighting metrics.

Photothermal CO2 hydrogenation is a promising approach for the conversion and valorization of CO2 into value-added products. However, challenges remain in balancing catalytic activity, selectivity, and stability, particularly for non-noble metal catalysts. In this work, a phase engineering strategy is introduced to synthesize CuCo heterophase nanoparticles via in situ photoreduction of oxide precursors under CO2 hydrogenation conditions. Experimental characterization reveals that the abundant Cu-Co3Cu interfaces act as atomic-level channels for photoelectron transfer and localized hot charge accumulation. These features synergistically improve full-spectrum light utilization and photothermal conversion efficiency. The optimal catalyst achieves a CO yield of 0.82mol g-1 h-1 under 3 W cm-2 full-spectrum light illumination and maintains ≈95% selectivity across 100 cycles. In situ spectroscopy combined with theoretical calculations suggests that the phase engineering enhances CO2 adsorption and activation while weakening CO binding, thereby suppressing methanation and enabling an optimal Sabatier balance. This interfacial engineering approach in heterophase nanostructures improves both stability and activity of non-noble metal catalysts in CO2 conversion and offers an effective pathway for developing efficient photothermal systems through rational interfacial engineering.

Mn4+-doped oxide red phosphors exhibit significant potential in full-spectrum lighting and plant growth lighting. Far-red emitting CaLuAlO4:Mn4+ phosphor was obtained by a high-temperature solid-phase method. In this structure, Mn4+ occupies the position of [AlO6], and exhibits two broad excitation bands in the 250-600 nm range. Upon 365 nm near-ultraviolet excitation, this phosphor exhibits far-red emission near 707 nm. Its internal quantum efficiency and absorptivity were measured to be 55.04% and 81.48%, respectively. CaLuAlO4:Mn4+ can compensate for the far-red emission deficiency of WLEDs, attaining a low correlated color temperature (CCT = 3548 K) and a high color rendering index (Ra = 96.5). Plant growth experiments using packaged far-red LED verified its positive effects on plant growth. These results demonstrate the potential of CaLuAlO4:Mn4+ red phosphors for applications in full-spectrum lighting and plant growth lighting.

Ce3+ → Pr3+ energy transfer and traps boosting thermal stability of KSrScSi2O7: Ce3+, Pr3+ phosphor for full-spectrum solid-state lighting

ABSTRACT Light serves as the main synchroniser of the circadian system. The amount of light and its spectral distribution throughout the day influence hormonal secretion and sleep-wake regulation. There is a knowledge gap regarding the impact of the spectrum and intensity reduction of short-wavelength light during the day on circadian system outputs. In the present study, 23 participants spent 5 working days in the reference office with full-spectrum lighting. In the experimental week, participants spent five working days in the office with reduced intensity and short-light spectrum up to 500 nm. We measured melatonin, cortisol, and salivary alpha-amylase (sAA) activity in morning and evening saliva under dim light or light exposure (LE) and sleep by wrist actigraphy. Daylight impacted sleep quality only in females. The melatonin did not differ due to a changed daylight, but the LE had a stronger suppressive effect during the experimental week. The cortisol in the morning was higher in females, with no differences between weeks. To conclude, modified daylight has an impact on sleep quality without significant hormonal or sAA changes. LE before sleep can influence melatonin and sleep quality depending on the previous light history with high interindividual differences.

GA participates in FR light-induced internode elongation of cucumber by regulating the expression of genes/proteins related to aquaporins, expansins, cell wall biosynthesis, hormone metabolism, and signal transduction. This study investigated the effects of the interaction between far-red (FR) light and gibberellin (GA) on the internode elongation of cucumber (Cucumis sativus L. 'Zhongnong No. 26') seedlings through combined physiological, biochemical, transcriptomic, and proteomic analyses. The results revealed that FR light and GA significantly promoted internode elongation in cucumber seedlings, whereas a GA biosynthesis inhibitor (PAC) inhibited the promoting effect of FR light. Hormone content determination revealed that FR light and GA decreased the contents of abscisic acid (ABA), indole-3-acetic acid (IAA), cytokinin (CTK), and jasmonate (JA) in cucumber seedling internodes. Bioinformatics analysis revealed that the expression patterns of the Co-DEGs and Co-DEPs were consistent in the FR (WL combined with FR light) and WLG (WL, in which plants were sprayed GA) groups, as well as in the FRP (FR, in which plants were sprayed PAC) and WL (full-spectrum LED white light) groups, suggesting that the mechanisms of FR and GA were similar in these Co-DEGs and Co-DEPs. Further analysis of these Co-DEGs and Co-DEPs revealed that they were involved mainly in cell wall biosynthesis and modification, lignin synthesis, hormone metabolism, and signal transduction pathways. In conclusion, this study revealed the important role of GA in FR light-induced internode elongation in cucumber seedlings, and this promoting effect was achieved mainly through the regulation of aquaporins, expansins, hormone metabolism, and signal transduction-related genes/proteins. This study provides new insights into the molecular mechanism of FR light-induced internode elongation in cucumber seedlings.

High-color-purity and full-spectrum white light emission of Sn2+/Mn2+ co-doped BaO-ZnO-P2O5 glasses and novel single-phase BaZnP2O7 glass-ceramics

Multi-site occupied Cs2Ba3(P2O7)2:Eu2+ phosphor with blue-green dual emission for full-spectrum lighting

Optimization of full-spectrum light absorption performance in all-inorganic perovskite solar cells doped with Ge2+

Understanding the mechanism of photocatalysis has long been a challenge, particularly its implications for photothermal reactions. The role of the particle nature of light in this field is well-recognized, while the other property involved in the duality of light remains neglected. This study bridges the gap between the classical and quantum mechanical perspectives of light's interaction with matter, unveiling the critical role of its wave properties. Through high-throughput experiments on pigment decomposition under varied temperatures and light wavelengths, combined with AI-driven analysis, we identify nonclassical kinetic behavior that deviates from the Arrhenius model. Our findings demonstrate that light's wave properties facilitate quantum tunneling, enabling chemical reactions below conventional energy barriers. This breakthrough highlights an independent, noncoupled influence of light and heat on catalytic processes. A novel theoretical framework integrating tunneling dynamics is introduced, offering superior predictive accuracy for reaction rates across experimental and literature data. This paradigm shifts the fundamental understanding of photocatalysis, paving the way for innovative catalytic systems leveraging light's full spectrum to enhance efficiency and selectivity.

Black soldier flies (BSF; Hermetia illucens) are insects known for their ability to upcycle food waste into useful agricultural products such as fertilizers, soil amendments, proteins, fats, and chitin. These qualities make BSF larvae pivotal in the food waste recycling industry. Consequently, significant research has been dedicated to optimizing larval growth conditions, while adult BSF behavior remains largely unexplored. This gap may impede further improvements in rearing operations and overall production. To address this, we tested BSF adults using a Y-tube olfactometer—a robust assay for olfaction—to evaluate the olfactory preferences of adult BSF. We compared the response rate of adult BSF to a known attractant and a negative control. Our experimental setup involves varied light conditions ranging from no light, fluorescent lamps, and a custom-made UV full spectrum light to simulate outdoor conditions. Our preliminary results suggest that BSF adults exhibit a higher response to the known attractant under full spectrum light, suggesting that specific lighting conditions enhance responsiveness to olfactory cues. These insights imply that light may play a crucial role in key behaviors such as oviposition, mating, and attraction. By better understanding these processes, we can refine BSF rearing techniques, which could lead to advancements in the waste recycling industry.

The inclusion of the Internet of Things (IoT) in indoor agricultural systems has become a fundamental tool for improving cultivation systems by providing key information for decision-making in pursuit of better performance. This article presents the design and implementation of an IoT-based agricultural system installed in a plant growth chamber for hydroponic cultivation under controlled conditions. The growth chamber is equipped with sensors for air temperature, relative humidity (RH), carbon dioxide (CO2) and photosynthetically active photon flux, as well as control mechanisms such as humidifiers, full-spectrum Light Emitting Diode (LED) lamps, mini split air conditioner, pumps, a Wi-Fi surveillance camera, remote monitoring via a web application and three Nutrient Film Technique (NFT) hydroponic systems with a capacity of ten plants each. An ATmega2560 microcontroller manages the smart system using the MODBUS RS-485 communication protocol. To validate the proper functionality of the proposed system, a case study was conducted using lettuce crops, in which the impact of different nutrient solution concentrations (50%, 75% and 100%) on the phenotypic development and nutritional content of the plants was evaluated. The results obtained from the cultivation experiment, analyzed through analysis of variance (ANOVA), show that the treatment with 75% nutrient concentration provides an appropriate balance between resource use and nutritional quality, without affecting the chlorophyll content. This system represents a scalable and replicable alternative for protected agriculture.

Efficient broadband green-emitting Ca2LuScGaAlSi2O12:Ce3+ garnet phosphor towards high-color-rendering full-spectrum WLED lighting

Exploring the potential of KSr6ScSi4O16:Eu2+ phosphors for full-spectrum light emitting diodes