Light Utilization Efficiency Research Articles

Multi‐scale Hierarchical Organic Photocatalytic Platform for Self‐Suspending Sacrificial Hydrogen Production from Seawater

The widespread application of photocatalysis for converting solar energy and seawater into hydrogen is generally hindered by limited catalyst activity and the lack of sustainable large‐scale platforms. Here, a multi‐scale hierarchical organic photocatalytic platform was developed, combining a photosensitive molecular heterojunction with a molecular‐scale gradient energy level alignment and micro‐nanoscale hierarchical pore structures. The ternary system facilitates efficient charge transfer and enhances photocatalytic activity compared to conventional donor‐acceptor pairs. Meanwhile, the super‐wetted hierarchical interfaces of the platform endow it with the ability to repeatedly capture light and self‐suspend below the water surface, which simultaneously improves the light utilization efficiency, and reduces the adverse effects of salt deposition. Under a Xe lamp illumination, the hydrogen evolution rate of this organic platform utilizing a sacrificial agent can reach 165.8 mmol h−1 m−2, exceeding that of mostly inorganic systems as reported. And upon constructing a scalable system, the platform produced 80.6 ml m−2 of hydrogen from seawater within five hours at noon. More importantly, the outcomes suggest an innovative multi‐scale approach that bridges disciplines, advancing the frontier of sustainable seawater hydrogen production driven by solar energy.

Nanoarchitectonics of MIL-101(Fe)/g-C3N4 S-Scheme heterojunction for photocatalytic nitrogen fixation: Mechanisms and performance

Recently, there has been a growing interest in the fundamental understanding of the mechanism of how MIL-101(Fe)/g-C3N4 heterojunctions facilitate the occurrence of photocatalytic nitrogen fixation reactions, especially the electron transfer mechanism has attained increasing attention in photocatalysis. Herein, we implemented a "triple win scenario" strategy to fabricate the S-scheme MIL-101(Fe)/g-C3N4 heterojunction through a straightforward solvothermal process. The MC-6 heterojunction minimizes the recombination of photogenerated carriers, enhances light utilization efficiency, and activates the N≡N bond, thus boosting photocatalytic nitrogen fixation efficiency. The transition metal iron activates the N≡N bond, while S-scheme heterojunctions reduce the photogenerated carrier recombination. In addition, the decrease in band gap (Eg) leads to an increase in visible light utilization efficiency. ISIXPS proved the mechanism of interelectron transfer of MIL-101(Fe)/g-C3N4 heterojunction under illumination. Upon the creation of the heterojunction, electrons migrate from g-C3N4 to MIL-101(Fe), establishing an inherent electric field due to the disparate Fermi levels between the two materials. The electrons (e-) on the g-C3N4 CB with a more negative reduction potential and the holes (h+) on the MIL-101(Fe) VB are retained, which increased the redox capacity to a great extent required for the reduction of N2 to NH3. The ammonia production efficiency of MC-6 photocatalyst was 160 µmol gcat-1 h-1, representing an 8-fold and 2.8-fold improvement over pristine g-C3N4 (20 µmol gcat-1 h-1) and MIL-101(Fe) (57 µmol gcat-1 h-1), respectively.

Initializing Compression Stress to Stabilize the Phase Homogeneity in Bifacial Semitransparent Perovskite Solar Cells

AbstractSemitransparent perovskite solar cells (ST‐PSCs) hold great promise for various commercial applications, including building integrated photovoltaics and tandem solar cells. The all‐inorganic perovskite, known for its outstanding optical transparency and thermal stability, emerges as a top contender for ST‐PSCs. However, challenges persist due to phase segregation, which hampers charge carrier transport and operational stability. In this study, an approach is proposed to address these challenges by employing strain engineering to reconstruct the perovskite texture, eliminating inhomogeneities within the perovskite film. The crucial role of compressive strain in stabilizing lattice rigidity and suppressing light‐induced ion migration is demonstrated. Furthermore, a transparent light‐harvesting architecture is devised utilizing a sandwiched layer of gold embedded between MoO3. This design enhances power generation by efficiently harnessing incident light from both the front and rear panel surfaces. Therefore, bifacial ST‐PSCs achieve an equivalent efficiency (ηeq) of 13.97% with an average visible light transmittance of 41.58%, yielding an outstanding light utilization efficiency of up to 5.8%. This research not only advances the understanding of perovskite material phase‐segregation behavior but also introduces an effective strategy for enhancing optical gain without compromising the semitransparent characteristics.

Integral morphology and structure design of poly (heptazine imide) for efficient utilization of visible light generated charge carriers in proton reduction reactions

AbstractSufficient utilization of visible‐light generated charge carriers in proton reduction reactions is of great significance for the development of effective solar‐fuel technologies. Achieving simultaneous bulk rapid transfer and surface efficient extraction of charge carriers is still very challenging. Herein, it is found for the first time ammonium persulfate (APS) can significantly influence polymerization processes of C3N4 (CN) from melamine to poly (heptazine imide) (PHI) under the simultaneous oxygen doping and etching effect of SO42−. PHI with high crystallinity, porous structure, and in‐situ oxygen doping was therefore obtained through one‐step APS‐assisted salt strategy. Benefiting from sufficient visible‐light absorption and upshifted conduction band originating from regulated electronic structure and optimized morphology through APS modification, the as‐prepared PHI achieved a H2 evolution activity of 3274.23 μmol h−1 g−1 (λ > 420 nm), which is appropriately 148 and 19 times that of conventional and crystalline CN. This work opens up new opportunities for efficient photocatalysis.

Fluorescence and electron transfer of Limnospira indica functionalized biophotoelectrodes

Cyanobacteria play a crucial role in global carbon and nitrogen cycles through photosynthesis, making them valuable subjects for understanding the factors influencing their light utilization efficiency. Photosynthetic microorganisms offer a promising avenue for sustainable energy conversion in the field of photovoltaics. It was demonstrated before that application of an external electric field to the microbial biofilm or cell improves electron transfer kinetics and, consequently, efficiency of power generation. We have integrated live cyanobacterial cultures into photovoltaic devices by embedding Limnospira indica PCC 8005 cyanobacteria in agar and PEDOT:PSS matrices on the surface of boron-doped diamond electrodes. We have subjected them to varying external polarizations while simultaneously measuring current response and photosynthetic performance. For the latter, we employed Pulse-Amplitude-Modulation (PAM) fluorometry as a non-invasive and real-time monitoring tool. Our study demonstrates an improved light utilization efficiency for L. indica PCC 8005 when immobilized in a conductive matrix, particularly so for low-intensity light. Simultaneously, the impact of electrical polarization as an environmental factor influencing the photosynthetic apparatus diminishes as matrix conductivity increases. This results in only a slight decrease in light utilization efficiency for the illuminated sample compared to the dark-adapted state.

Light footprint of microalgae cultivation system addressed by modified Cornet model

The cultivation of microalgae is significantly influenced by light intensity and utilization efficiency. This study developed a modified Cornet (M−Cornet) model to assess the distribution of light intensity and flux in microalgae cultivation systems. Algal biofilm cultivation represents a more concentrated approach of algal suspension cultivation. Both follow the M−Cornet model and exhibit the same growth rates when cultured under identical conditions. Algal pigments and morphologies greatly impact the light absorption and scattering, resulting in light attenuation in intensity, penetration distance and light flux distribution. Algae varieties exhibit diverse light flux characteristics. 37% − 90% of the incident light is absorbed, of which, 80% to 90% is dissipated as heat. 10% to 63% of the incident light is scattered off the photobioreactor. The overall light utilization efficiency ranges 6% to 13%. The light footprint using the M−Cornet model offers valuable insights for photobioreactors designing and cultivation operating.

Color-restoring and energy-saving imaging monitoring for intelligent offshore engineering

Images play a crucial role in artificial intelligence (AI) for offshore engineering, which provide a large amount of data for machine intelligence to ensure the safe operation and maintenance of offshore structures. However, due to the attenuation of sunlight in water or monitoring at nighttime, underwater imaging monitoring systems need a light source, which consumes a lot of energy and impacts the load capacity of an offshore monitoring system. In addition, due to the nonlinearity of attenuation at different wavelengths, underwater images generally suffer from color deviation, tending to be blue and green, which decreases the accuracy of machine learning and intelligent recognition in unmanned offshore engineering. In order to reduce energy consumption and enhance color restoration, we proposed and designed a three-detector underwater imaging system (TD&TP-UIS) based on a prism, in which three detectors were used to enhance the utilization efficiency of light, and a gated band coating was designed on the prism to enhance the color reproduction. A series of experiments were carried out in water tanks, pools, Qiandao Lake, and other places to verify the advantage of color restoration and energy saving using the TD&TP-UIS.

In situ constructed Bi5O7I/NiO-NF heterojunction on 3D nickel foam for photocatalytic sulfamerazine degradation: Structure-performance, application, and mechanism

Photocatalysis is a promising technology for water purification, but the inadequate separation of photogenerated charge carriers and light utilization efficiency limits its practical application. Herein, a highly solar-responds photocatalyst Bi5O7I/preoxidized nickel foam (Bi5O7I/NiO-NF) with p-n heterojunction was constructed by impregnation and microwave-assisted co-precipitation method to remove typical antibiotic efficiently. The special pretreatment is conducive to the formation of NiO on the NF surface, which participates in the construction of p-n heterogeneous structures and strengthens the bonding force between NiO-NF and surface Bi5O7I. The macroscopic renewable Bi5O7I/NiO-NF could effectively degrade sulfamerazine (SMR) nearly 100 % under sunlight irradiation and be convenient for separating from aqueous. Variety pollutants are degraded with high efficiency in the solar Bi5O7I/NiO-NF system, and the system performs the resistance to co-existing ions (≥89 % removal efficiency) and water matrix interference (≥95 % removal efficiency). Quenching experiments and electron paramagnetic resonance spectroscopy characterization results indicate that h+, 1O2 and O2− are the dominant reactive substances in SMR elimination. Based on the DFT calculation and quadrupole-time of flight-liquid chromatography/mass spectrometry (Q-TOF-LC/MS) detection, C-S and N-S bonds tend to be attacked in the SMR degradation pathway. This work opens up novel insights for constructing efficient macroscopic photocatalysts for practical water treatment.

Enhancing Light Utilization Efficiency of Semi‐Transparent Perovskite Solar Cells via Tailored Interfacial Engineering

AbstractSemi‐transparent perovskite solar cells (ST‐PSCs) are promising for their application in building integrated photovoltaics (BIPVs). For BIPVs, a light utilization efficiency (LUE) > 2.5 is required which is multiplication of average visible transmittance (AVT) and power conversion efficiency (PCE). Generally, semitransparency is achieved by reducing film thickness which increases AVT but decreases PCE resulting in lower LUE. Here, an interface engineering strategy is employed on a wide bandgap perovskite thin absorber layer to increase PCE and LUE. The study employs three different alkylamine hydrochlorides molecules with varied alkyl chain length, viz., 2‐chloroethylamine‐hydrochloride, 3‐chloropropylamine‐hydrochloride, and 4‐chlorobutyalamine‐hydrochloride at perovskite/electron transport layer (ETL) interface and investigates their effect on perovskite crystallization. Further, it is demonstrated that 4‐chlorobutyalamine‐hydrochloride can strongly interact with perovskite and suppress non‐radiative recombination facilitating charge transport at the perovskite/ETL interface. Devices post‐treated with 4‐chlorobutyalamine‐hydrochloride interfacial layer, demonstrate a higher LUE of 3.45% (PCE 14.11%) and AVT of ≈25% (400–800 nm), with Voc of 1.23 V. Moreover, the unencapsulated devices retain ≈89% of the initial efficiency after storage for 1500 h under a relative humidity of ≈35–40%. This study provides an efficient approach to improve LUE and stability of ST‐PSCs for the application in energy‐efficient smart windows.

Near-infrared light-driven biomass conversion.

Current photocatalytic technologies mainly rely on the input of high-energy ultraviolet-visible (UV-vis) light to obtain the desired excited states with adequate energy to drive redox reactions, precluding the use of low-energy near-infrared (NIR) light that occupies ~50% of the solar spectrum. Here, we report the efficient utilization of NIR light by coupling the low-energy NIR photons with reactive biomass conversion. A unique mechanism of photothermally synergistic photocatalysis was revealed for the selective biomass conversion under NIR light. Using biomass-derived 5-hydroxymethylfurfural (HMF) conversion as a model reaction, it was found that NIR and UV-vis light featured markedly different reaction patterns. 5-Formyl-2-furancarboxylic acid (FFCA) was almost exclusively produced under NIR light, whereas UV-vis light favored the formation of 2,5-diformylfuran (DFF) as the major product. This work provides a paradigm for sustainable and selective chemical synthesis using the Earth's abundant resources, sunlight and biomass.

Dielectric Bragg Reflector as Back Electrode for Semi‐Transparent Organic Solar Cells with an Average Visible Transparency of 52%

A crucial challenge in the development of semi‐transparent solar cells is to maintain a reasonable power conversion efficiency (PCE) while reaching a high average visible transparency (AVT). Typically, organic semiconductors are favorable for this application since they can selectively absorb infrared light while transmitting visible light. This ability stems from limited electronic states at high(er) energies in contrast to inorganic semiconductors with their typical rise of the absorption coefficient toward higher photon energies. To increase PCE at high AVTs, a series of infrared dielectric Bragg reflectors is developed for semi‐transparent organic solar cells. Using the multi‐layered back electrode (TiO2|SiN|TiO2|AZO|Ag|AZO) with PV‐X Plus as photoactive layer and a metal‐free PEDOT:PSS top electrode, a light utilization efficiency (LUE = AVT × PCE) of up to 4.32% is achieved, together with an AVT of 47.9%. Although the short circuit current and AVT agree well with optical simulations, a low fill factor (FF) and partial shunting limit the overall device performance. Using ZnO and PFN‐Br as additional electron transport layers and modifying the back electrode stack (TiO2|SiO2|TiO2|AZO|Ag|AZO) accordingly leads to an LUE of up to 4.6% with a remarkable AVT of 51.9% and a maximum PCE of 8.79%.

Promoting Photon-to-Chemical Conversion through a Dielectric Antenna-Hybrid Bilayered Reactor Configuration.

The application of scattered light via an antenna-reactor configuration is promising for converting thermocatalysts into photocatalysts. However, the efficiency of dielectric antennas in photon-to-chemical conversion remains suboptimal. Herein, we present an effective approach to promote light utilization efficiency by designing dielectric antenna-hybrid bilayered reactors. Experimental studies and finite-difference time-domain simulations demonstrate that the engineered SiO2-carbon/metal dielectric antenna-hybrid bilayered reactors exhibit a synergy of absorption superposition and electric field confinement between carbon and metals, leading to the improved absorption of scattered light, upgraded charge carriers density, and ultimately promoted photoactivity in hydrogenating chlorobenzene with an average benzene formation rate of 18 258 μmol g-1 h-1, outperforming the reported results. Notably, the carbon interlayer proves to be more effective than the commonly explored dielectric TiO2 interlayer in boosting the benzene formation rate by over 3 times. This research paves the way for promoting near-field scattered photon-to-chemical conversion through a dielectric antenna-hybrid reactor configuration.

Optimization Light Utilization Efficiency of Semitransparent Organic Solar Cells by Regulating Absorption Spectrum

Optimization Light Utilization Efficiency of Semitransparent Organic Solar Cells by Regulating Absorption Spectrum

Effects of Planting Density and Nitrogen Management on Light and Nitrogen Resource Utilization Efficiency and Yield of Summer Maize in the Sichuan Hilly Region

The low efficiency of light and nitrogen resources, poor yield and profit, and environmental pollution of maize production are main problems in many areas of China. We hypothesized that optimizing nitrogen fertilizer density management strategies could alleviate the above issues. To address this, a 3-year on-site experiment with three planting densities and four nitrogen rates was conducted in the Sichuan Hilly Region. The results indicated that increasing the planting density could increase the extinction coefficient and solar radiation interception of maize populations as well as enhance the utilization efficiency of light and nitrogen resources and yield. For every 100 kg ha−1 increase in nitrogen fertilizer, RUE increased by 0.16%, NUE decreased by 25.0%, and soil apparent nitrogen loss quantity increased by 67.8 kg ha−1. There was a certain interaction between planting density and nitrogen rate. The appropriate planting density and nitrogen rate combination was 67,500 plants ha−1 with 180 kg N ha−1 under the experimental condition. Excessive close planting in weak-light areas and excessive nitrogen reduction after densification are not advisable. This study indicated that nitrogen–density strategies should be matched with the local natural resources such as sunlight. The results provide a theoretical for high-yield and high-quality maize production in these areas.

In2S3-modified ZnIn2S4 enhanced photogenerated carrier separation efficiency and photocatalytic hydrogen evolution under visible light

ZnIn2S4 (ZIS) has limited photocatalytic hydrogen production due to low visible light utilisation and insufficient separation efficiency of photogenerated carriers. This study utilized a simple hydrothermal method to prepare In2S3/ZnIn2S4 (INS/ZIS) heterojunctions. The addition of In2S3 (INS) improves the separation and movement of photogenerated charges, and makes better use of visible light. The material was analysed using SEM, TEM, XRD, XPS and photoelectrochemical tests. Results from the transient photocurrent (TPR) and photoluminescence (PL) experiments show a photocurrent density of approximately 1.8 μA/cm2, which is 3 times greater than the ZIS (0.6 μA/cm2) density, when the INS mass is 5 %. And at this time, INS/ZIS boasts the most effective photogenerated carrier separation. The hydrogen photocatalytic generation test results showed that the photocatalytic hydrogen production rate of 5-INS/ZIS (5690 μmol/g/h) was 8.4 and 66.9 times higher than that of pure ZIS (710 μmol/g/h) and INS (89 μmol/g/h), respectively. The enhanced activity is due to the creation of type II heterojunctions, which improve the separation and transfer of light-generated charges. The research presents an innovative approach to creating composites based on ZIS.

Fabrication of S-scheme graphdiyne (g-CnH2n-2)/carbon-nitrogen vacancies hollow Ni–Fe prussian blue analogues heterojunction for boosting wide spectrum photocatalytic hydrogen evolution

Efficient photocatalytic hydrogen evolution can be achieved by adjusting the morphology and constructing suitable heterojunction. In this work, an 2D/3D S-scheme graphdiyne (g-CnH2n-2)/carbon-nitrogen vacancies hollow Ni–Fe prussian blue analogues (Ni–Fe–CN PBA) heterojunction (GNF-CN) was prepared for photocatalytic hydrogen evolution. Ni–Fe–CN PBA were prepared by chemical etching and high temperature calcination. The hollow structure can realize multiple reflections of incident light and effectively improve the light utilization efficiency. The CN vacancy changes the band structure of Ni–Fe PBA and enhances its light absorption capacity. Graphdiyne nanosheets (GDY) prepared by load ball milling can increase the active site. The key lies in the construction of an S-scheme heterojunction between GDY and Ni–Fe–CN PBA, which effectively consume useless holes and increase the utilization rate of photogenerated electrons. The S-scheme electron transfer path are proved by DFT calculation, work function and in situ XPS. The GNF–CN–20 showed excellent photocatalytic hydrogen evolution activity (3755.02 μmol h−1 g−1) and photostability compared with GDY (1116.54 μmol h−1 g−1). The present study introduces a novel approach for the construction of an S-scheme heterojunction based on GDY and PBA, enabling wide‐spectrum‐responsive photocatalytic hydrogen evolution.

Efficient photocatalytic H2O2 production and photodegradation of RhB over K-doped g-C3N4/ZnO S-scheme heterojunction

Designing efficient dual-functional catalysts for photocatalytic oxygen reduction to produce hydrogen peroxide (H2O2) and photodegradation of dye pollutants is challenging. In this work, we designed and fabricated an S-scheme heterojunction (g-C3N4/ZnO composite photocatalyst) via one-pot calcination of a mixture of ZIF-8 and melamine in the KCl/LiCl molten salt medium. The KCN/ZnO composite produced 4.72 mM of H2O2 within 90 min under illumination (with AM 1.5 filter), which is almost 1.3 and 7.8 times than that produced over KCN and ZnO, respectively. Simultaneously, the KCN/ZnO also showed excellent photodegradation performance for the dye pollutants (Rhodamine B, RhB), with a removal rate of 92 % within 2 h. The apparent degradation rate constant of RhB over KCN/ZnO was approximately 5–8 times that of KCN and ZnO. In the photocatalytic process, photo-generated holes and superoxide radicals are the main active species. Oxygen (O2) was mainly reduced to produce H2O2 via a two-electron (2e−) pathway with superoxide radicals as intermediates and the 2e− oxygen reduction reaction selectivity of KCN/ZnO was close to 69.82 %. Photo-generated holes are mainly responsible for the degradation of RhB. Compared with pure KCN and ZnO, the enhanced photocatalytic activity of the KCN/ZnO composite is mainly attributed to the following aspects: 1) larger specific surface area and pore volume is beneficial to expose more active sites; 2) stronger light harvesting ability and red-shifted absorption edge bestow the compound a stronger light utilization efficiency; 3) the construction of S-scheme heterostructure between KCN and ZnO improve the photogenerated electron-hole pairs separation ability and bestow photogenerated carriers a higher redox potential.

A hollow core-shell TiO2/NiCo2S4 Z-Scheme heterojunction photocatalyst for efficient hydrogen evolution

Constructing heterojunctions have received significant attention in photocatalysis because of their efficient separation of photogenerated carriers and improving light utilization efficiency. Bimetallic sulfides (e.g. NiCo2S4) are applied in electrocatalysis and supercapacitors that can be coupled with TiO2 to form a heterojunction. Owing to the staggered energy band arrangement between TiO2 and NiCo2S4, the establishing of a Z-scheme heterojunction between them is expected to enhance the carrier separation efficiency and reduce the sulfide photo-corrosion. However, the application of NiCo2S4 in photocatalysis and studies on the mechanism of the TiO2/NiCo2S4 Z-scheme heterojunction have seldom been reported. In this work, we obtained a hollow core-shell TiO2/NiCo2S4 Z-scheme photocatalyst through a solvothermal method for photocatalytic hydrogen evolution (PHE). The PHE rate of the optimized TiO2/NiCo2S4-0.3 is 8.55 mmol g−1 h−1, approximately 34 times higher than pure TiO2, 94 times higher than pure NiCo2S4. The remarkable photocatalytic activity can be ascribed to the hollow structure and the in-situ constructed Z-scheme heterojunction. The photogenerated charge transfer mechanism is revealed by hydroxyl radical trapping experiments and electron paramagnetic resonance (EPR) characterization. The in-situ construction of the Z-scheme heterojunction not only enhances the efficiency of separating the photogenerated carriers but also reduces the photo-corrosion of NiCo2S4. This study proposes an effective strategy for the design of TiO2-based Z-scheme heterojunctions and the application of NiCo2S4 in photocatalysis.

Insights into the function of metallic 1T phase tungsten disulfide as cocatalyst decorated zinc indium sulfide for enhanced photocatalytic hydrogen production activity

Improving the separation efficiency of carriers is an important part of enhancing photocatalytic activity. Herein, we successfully decorated metallic 1T phase tungsten disulfide (1T-WS2) on the surface of zinc indium sulfide (ZnIn2S4) and investigated the synergistic effect of 1T-WS2 on ZnIn2S4. The characterization results show that 1T-WS2 improves the light absorption capacity and utilization efficiency, increases the catalytic active site, improves the photogenerated charge separation efficiency, and optimizes the reduction potential of ZnIn2S4. Theoretical calculations show that compared with ZnIn2S4, 1T-WS2/ZnIn2S4 has a smaller adsorption Gibbs free energy of the intermediate state H*, which is conducive to the catalytic reaction. Under simulated solar irradiation, the hydrogen (H2) production rate of 1T-WS2/ZnIn2S4 with a loading of 12 wt% reaches 30.90 mmol h−1 g−1, which is 3.38 times higher than that of single ZnIn2S4 (9.13 mmol h−1 g−1). In addition, the apparent quantum efficiency of 1T-WS2/ZnIn2S4 with a loading of 12 wt% reaches 21.14 % under monochromatic light at a wavelength of λ = 370 nm. This work analyzes the light absorption and carrier separation to the catalytic site, and elucidates the mechanism for the enhancement of the photocatalytic hydrogen production performance.

Contrasting light capture strategies between shade-tolerant and -intolerant tree seedlings responding to solar canopy spectral composition

Forest regeneration is a crucial ecological process for promote self-reproduction and restoration, which is essential for maintaining complex community structure and preserving biological resources. Although sunlight have been considered as the main driver of forest regeneration, how light quality shapes functional traits of seedlings is poorly understood in the forest understorey, where spectral compositions of solar radiation change dramatically. We investigated the responses of 15 typical functional traits of Pinus koraiensis and Quercus mongolica to five filter treatments that differed in the spectral transmittance: (a) 95 % of solar radiation was transmitted (280–700 nm); (b) ultraviolet (UV)-B radiation was attenuated (>315 nm); (c) all UV radiation was attenuated (>400 nm); (d) all UV radiation and blue light was attenuated (>500 nm); (e) all UV radiation, blue-green light was attenuated (>580 nm). Our results showed that functional traits responded to UV-B radiation (contrasting treatment [a] vs. [b]) with species-dependence, but consistently showed a positive response to blue light (contrasting treatment [c] vs. [d]). UV-B radiation decreased the relative growth rate (RGR) and leaf area ratio (LAR) of P. koraiensis seedlings by 48 % and 42 %, respectively; however, it increased seedling height, total leaf area (TLA), and above-ground biomass of Q. mongolica. Blue light consistently increased LAR and RGR of two species. Furthermore, Q. mongolica was more plastic in morphological traits (including plant height and TLA) and root/shoot ratio than P. koraiensis to the single spectral region (UV-B, UV-A, blue, and green light), but opposite in physiological and biochemical traits (such as chlorophyll and anthocyanidin). These suggest that two studied species have evolved different light capture strategies in the understorey: Q. mongolica seedlings tended to adjust morphology and biomass allocation to enhance light interception capacity, while P. koraiensis seedlings preferred to adjust physiological and biochemical traits to enhance light utilization efficiency. A better understanding how canopy spectral compositions affect seedling regeneration may provide a new insight for future forest management (i.e. the appropriate gap creation or tree species combination).