Indoor Lighting Conditions Research Articles

Flexible OPV modules for highly efficient indoor applications

The comparison of solution processed organic photovoltaics with two roll-to-roll coated electron transport layers (ETL), as well as printed grid or solid back electrodes provides insight into the future of R2R fabricated architectures. The variation in performance of the R2R slot-die coated zinc oxide (ZnO) versus the tin oxide (SnO2), showed a clear dependence on the spectrum of the illumination source. It was found that under indoor light conditions (200–1000 lux LED and fluorescent sources) the SnO2 outperformed the ZnO with highest efficiencies near 13% and 10% respectively. This is in contrast to results obtained under 1 Sun (AM 1.5) in which the cells fabricated with a ZnO ETL had a higher power conversion efficiency than those prepared with SnO2. The results also confirm the significance of the layout of the printed silver back contact; in which cells with the grid structure outperformed those with full coverage by approximately 35% for ZnO and just under 10% for SnO2 (all light conditions). The combination of a R2R coating and S2S printing process to prepare modules with 8 cells in series (PET/ITO/SnO2/PV2001:PCBM/PEDOT:PSS/silver grid) resulted in a PCE of 13.4% under indoor office light conditions.

Testing multisensory stimuli to drive thermal comfort and space perception using VR/AR: a design strategy to achieve energy saving

Energy consumption of the EU has a crucial environmental impact; several efforts are nowadays thus directed into massively reducing energy consumption by envelope improvement, system efficiency and smart control. On the other hand, the indoor thermal and lighting conditions significantly influence users' wellbeing and productivity, which is especially important when dealing with educational and working facilities. Strategies to enhance system efficiency are focused on design and construction aspects. These strategies ease to promote a powerful approach which is needed when focusing on existing buildings in need of retrofit measures. When dealing with new or refurbished buildings, energy saving has a further step to achieve. In the last years, research trends moved towards an increasing inclusion of human factors in energy evaluation. This allows to account for the occupancy variability in the energy analyses, considering how to bridge the performance gap between predictive models and actual consumptions due to indoor thermal settings. In empty buildings energy consumption is huge and economic efforts are wasted, due to unconscious energy-wasting behaviors. Previous studies with Interactive Virtual Environments confirmed that indoor environments illuminated by different color lights lead to the perception of different levels of thermal comfort. The results of the present paper replicate previous evidence collected in real conditions, suggesting that Virtual Reality is a valid and reliable tool to assess thermal comfort more quickly and cheaply. This paper provides a further perspective on this topic, including also the use of different fragrances to understand how the indoor environment could be enhanced and manipulated to increase wellbeing, thermal perception and finally energy saving.

A2Event: A Micro-Watt Programmable Frequency-Time Detector for Always-On Energy-Neutral Sensing

Internet of Things (IoT) sensors are becoming more and more intelligence and unobtrusive, surrounding us in everyday life. A key requirement for those devices is to be “always-on” performing “smart” detection to catch only the events of interest when they occur. A recent and trend is to design low power circuit to extract features close to the sensors without an analog-digital conversion. The goal is to achieve place-and-forget deployment with perpetual operation: this poses the challenge of achieving micro-watt power consumption of the always-on analog event detector and of harvesting energy from environmental sources, to supply the smart sensor. This paper presents A2Event (Analog to Event), a microwatt programmable pattern recognition circuit for analog sensors, with up to 128 simultaneous time-frequency features exploiting mixed-signal low power design, which is able to generate an event when a targeted pattern is recognized. Moreover, the paper proposes a self-sustaining always-on smart audio detector that combines A2Event with energy harvesting to detect events of interests perpetually. Experimental results show that A2Event consumes only 26.89 μW in always-on mode, during the time-frequency feature-extraction, while the whole system consumes only 63 μW during pattern recognition including the power for a commercial MEMS microphone and the energy harvesting subsystem. We demonstrate that the whole smart sensor operates perpetually when powered with a small form factor flexible photovoltaic panel in indoor lighting conditions, achieving a detection accuracy of 100% in the detection of two different audio streams.

Understanding the Spatial Heterogeneity of Indoor OH and HO2 due to Photolysis of HONO Using Computational Fluid Dynamics Simulation.

Indoor photolysis of nitrous acid (HONO) generates hydroxyl radicals (OH), and since OH is fast reacting, it may be confined within the HONO-photolyzing indoor volume of light. This study investigated the HONO-photolysis-induced formation of indoor OH, the transformation of OH to hydroperoxy radicals (HO2), and resulting spatial distributions of those radicals and their oxidation products. To do so, a computational fluid dynamics (CFD) model framework was established to simulate HONO photolysis in a room and subsequent reactions associated with OH and HO2 under a typical range of indoor lighting and ventilation conditions. The results showed that OH and HO2 were essentially confined in the volume of HONO-photolyzing light, but oxidation products were relatively well distributed throughout the room. As the light volume increased, more total in-room OH was produced, thereby increasing oxidation product concentrations. Spatial distributions of OH and HO2 varied by the type of artificial light (e.g., fluorescent versus incandescent), due to differences in photon flux as a function of light source and the distance from the source. The HO2 generation rate and air change rate made notable impacts on product concentrations.

$256\times8$ SPAD Array With 256 Column TDCs for a Line Profiling Laser Radar

A receiver circuit for pulsed time-of-flight line profiling laser radar has been designed in $0.35\mu \text {m}$ CMOS technology. The receiver consists of a line detector array with $256\times 8$ SPADs with a pitch of $41.6\mu \text {m}$ . The diameter of the SPAD’s active area is $25.6\mu \text {m}$ , which gives a fill factor of 0.35. Each column has 8 SPADs and a TDC with a range and resolution of 640 ns and 20 ps, respectively. The TDCs are based on the Nutt interpolation method where cyclic converters are utilized as fine converters. A compact demonstrator system has been built with a horizontal FOV of about 37°, which gives a column-wise angular resolution of about 0.15°. This solid-state system uses a pulsed laser diode with cylindrical transmitter optics to illuminate the full FOV of the receiver with a single laser pulse. The system can measure distances up to 30 m @ 28 fps with an accuracy and precision of few millimeters in typical indoor lighting conditions. Outdoors, in direct sunlight conditions, the measurement range is decreased to 5 m. Outdoor range, however, can be increased if frame rate is lowered and more laser shots are accumulated per frame.

High-Efficiency Bifacial Dye-Sensitized Solar Cells for Application under Indoor Light Conditions.

High-efficiency, stable bifacial dye-sensitized solar cells (DSSCs) are prepared for application under indoor light conditions. A 3-methoxypropionitrile solvent and cobalt redox couples are utilized to prepare the electrolytes. To obtain the best cell performance, the components of the DSSCs, including electrolytes, photoanodes, and counter electrodes (CEs), are regulated. The experimental results indicate that an electrolyte comprising a Co (II/III) ratio of 0.11/0.025 M, 1.2 M 4-tert-butylpyridine, Y123 dye, a CE with the platinum (Pt) layer thickness of 0.16 nm, and a photoanode with titanium dioxide (TiO2) layer thickness of 10 μm (6 μm main layer and 4 μm scattering layer) are the best conditions under which to achieve a high power conversion efficiency. It is also found that the best cells have high recombination resistance at the photoelectrode/electrolyte interface and low charge transfer resistance at the counter electrode/electrolyte interface, which contributes to, respectively, the high current density and open-circuit voltage of the corresponding cells. This DSSC can achieve efficiencies of 22.66%, 23.48%, and 24.52%, respectively, under T5 light illumination of 201.8, 607.8, and 999.6 lx. For fabrication of bifacial DSSCs with a semitransparent property, photoanodes without the TiO2 scattering layer, as well as an ultrathin Pt film, are utilized. The thicknesses of the TiO2 main layer and Pt film are reregulated. This shows that a Pt film with 0.55 nm thickness has both high transmittance (76.01%) and catalytic activity. By using an 8 μm TiO2 main layer, optimal cell efficiencies of 20.65% and 17.31% can be achieved, respectively, for the front-side and back-side illuminations of 200 lx T5 light. The cells are highly stable during a long-term performance test at both 35 and 50 °C.

A transparent and Pt-free all-carbon nanocomposite counter electrode catalyst for efficient dye sensitized solar cells

Recently, substantial focus has made in the development of cost effective Pt-free dye sensitized solar cells (DSSCs). In this article we report a potential, Pt-free, carbon based nanocomposite as counter electrode catalyst for dye sensitized solar cells. Graphene oxide (GO) was made into reduced graphene oxide (SSrGO) by irradiating with light (Xe source). Suspension of SSrGO in DMF was spray coated onto fluorine doped tin oxide (FTO) coated glass substrate, followed by spray coat of single walled carbon nanohorns (SWCNH) suspension in DMF. SSrGO and SWCNH coated FTO glass substrate was investigated as an effective Pt-free composite counter electrode (CE) for DSSC and also showed the comparable catalytic activity with Pt. The test cell reveals power conversion efficiency (PCE) of 8.27%, whereas the DSSC module exhibited a PCE of 5.18%. By using the fabricated DSSC module, an electric motor (15 mW) was operated both in indoor and outdoor light conditions. The procedures followed in this work pave a way for the easy fabrication of composite CE towards transparent DSSC modules and further the integration of the DSSC module with the standard Si solar cell is of great potential for various real-time application.

Light and Life at Night as Circadian Rhythm Disruptors

Light is an important entraining agent for endogenous circadian rhythms. Artificial light at night (ALAN) negatively influences the circadian system, inducing acute effects on sleep and cognition, as well as chronic endocrine-disrupting effects resulting in obesity, cardiovascular disease, diabetes, and cancer. Although shift workers may be exposed to extreme ALAN, its impact on their health is obscured by factors such as daylight exposure, meal and sleep scheduling, and physical and social behavior. Studies have revealed a significant increase in breast cancer in high ALAN-polluted areas, although the correlation with outdoor or indoor lighting conditions is controversial. Increasing use of electronic devices makes it difficult to assess ALAN exposure in the general population. The development of surrogate markers and critical parameters is crucial for health study by ALAN exposure, and such markers should include risk factors related to ALAN exposure. The present review considers articles investigating the risk of ALAN for shift workers, the general population, and users of electronic devices, and addresses susceptibility factors, including age, sex, and chronotype. Shift workers may be regarded as an extreme ALAN-exposure group, but the growing use of electronic devices and lifestyle changes in the general population make difficult to differentiate ALAN risks to health. Keywords: Circadian rhythm; Sleep disruption; Cognition; Melatonin; Shift work

Dynamic Enhancement of Nitric Oxide Radioluminescence with Nitrogen Purge

Remote detection of alpha radiation is commonly realised by collecting the light, the radioluminescence, that is produced when alpha particles are stopped in air. Radioluminescence of nitric oxide (NO) is primarily emitted between 200 nm and 300 nm, which makes it possible to use it for remote detection under daylight conditions. Quenching by ambient oxygen and water vapour, however, makes it generally difficult to effectively create NO radioluminescence. We present the detection of intense NO radioluminescence in ambient air under standard indoor lighting conditions using a nitrogen purge. The nitrogen contained NO impurities that were intrinsic to the gas and had not explicitly been added. We study the mechanisms that govern the NO radioluminescence production and introduce a model to describe the dynamics of the process. The level of NO contained in the gas was found to determine how successful a purge can be. We conclude by discussing possible applications of the technique in nitrogen-flushed gloveboxes at nuclear facilities where NO concentration of 100 ppb–1 ppm would be sufficient for efficient optical alpha radiation detection in standard lighting conditions.

Comfortable indoor lighting conditions for LEDlights evaluated from psychological and physiological responses

Comfortable light emitting diode (LED) lighting conditions were examined for psychological and physiological responses. Eight male and eight female subjects participated in a series of experiments. They were exposed to light emitted from LED lights of 3000 K in the ranges of 150–400 lux and 1500–5000 lux; 4000 K in the ranges of 140–640 lux and 2000–5000 lux; and 5000 K in the ranges of 70–270 lux and 2500–7000 lux. Illuminance at a given correlated color temperature was first maintained at the lowest value in the designated range and then increased in a stepwise manner. On reaching the highest value in the range, it was then decreased to the lowest value in a stepwise manner. The subjects were required to indicate their perception of brightness, glare, and comfort at the controlled illuminance levels. Electrocardiogram and electroencephalogram data were monitored continuously throughout exposure. The results showed that the boundary illuminances estimated from psychological and physiological responses did not significantly differ between male and female subjects, but differed markedly from those of fluorescent lights tested in a previous study. The high boundaries of the LED lights were higher than those of the fluorescent lights. The low boundaries of the LED lights at 3000 K and 4000 K were higher than those of the fluorescent lights, but the boundaries at 5000 K were lower than those of the fluorescent lights. These differences may be due to differences in the spectral distribution and luminance for a given illuminance between LED and fluorescent lights.

Bandgap Engineering Enhances the Performance of Mixed‐Cation Perovskite Materials for Indoor Photovoltaic Applications

AbstractIndoor photovoltaics (IPVs) are attracting renewed interest because they can provide sustainable energy through the recycling of photon energy from household lighting facilities. Herein, the Shockley–Queisser model is used to calculate the upper limits of the power conversion efficiencies (PCEs) of perovskite solar cells (PeSCs) for two types of artificial light sources: fluorescent tubes (FTs) and white light–emitting diodes (WLEDs). An unusual zone is found in which the dependence of the PCEs on the bandgap (Eg) under illumination from the indoor lighting sources follows trends different from that under solar irradiation. In other words, IPVs exhibiting high performance under solar irradiation may not perform well under indoor lighting conditions. Furthermore, the ideal bandgap energy for harvesting photonic power from these indoor lighting sources is ≈1.9 eV—a value higher than that of common perovskite materials (e.g., for CH3NH3PbI3). Accordingly, Br− ions are added into the perovskite films to increase their values of Eg. A resulting PeSC featuring a wider bandgap exhibits PCEs of 25.94% and 25.12% under illumination from an FT and a WLED, respectively. Additionally, large‐area (4 cm2) devices are prepared for which the PCE reaches ≈18% under indoor lighting conditions.

Deep Learning Method for Video-Based Data to Classify Peripheral Edema Grades

Introduction Peripheral edema is a common precursor to decompensation for patients with heart failure (HF), and commonly measured with the pitting test. Video recordings of the pitting peripheral edema test can capture details of skin topography and time-evolution of tissue recovery with much greater precision than a human eye. Video-based deep learning can potentially overcome the subjectivity of the peripheral edema test and assist patients in identifying objective changes in their peripheral edema. We have previously shown that our deep learning model can accurately estimate peripheral edema grade with 98% accuracy using physical edema models. The objective of this study was to evaluate feasibility of collecting videos of peripheral edema from hospitalized patients with heart failure who have various skin colors and features for the purpose of refining the deep learning model for automated edema classification. Methods We enrolled 18 patients from February-April, 2019 from cardiac medical, surgical, and intensive care units at an urban university medical center. Patients were first screened for peripheral edema through the inpatient electronic medical record system. After meeting enrollment criteria and signing informed consent, trained personnel recorded 10 videos of the pitting test on patients with peripheral edema each day of their hospitalization using a Samsung Galaxy S9 phone. The personnel used one index finger to make a circular pit on the left and right side of three bony prominences (foot, ankle, and shin). Videos were taken freehand, under diffuse indoor light conditions and were 5 seconds to 2 minutes long, depending on the time it took for the skin/tissue to fully rebound from the pitting test. Each video was labeled independently with the edema grade by a research assistant and nurse, and downloaded from a secure endpoint (phone) to a central database for analysis. Results We collected 376 videos from 18 patients over an average of three days. Overall, the sample of participants was 16% female, 33% Black, 11% Hispanic and had grades of edema that ranged from grade 0 (12%), grade 1 (51%), grade 2 (18%), grade 3 (9%), and grade 4 (10%). The videos contained a wide variability of diverse skin tones and features to ensure that the method is robust and generalizable to a multiracial patient population (Figure 1). Discussion We established the feasibility of collecting videos of peripheral edema from hospitalized patients with HF. Deep learning holds promise for the automatic classification and objective measurement of clinical signs captured with video data.

Tracking a Golf Ball With High-Speed Stereo Vision System

Professional long drivers can hit golf balls to a speed of up to 350 km/h. Extremely short exposure time is required to capture the objects moving that fast without blur. The very high frame rate is also required to capture the sufficient sequence of object movements within the field of view in order to predict trajectory, which means a sacrifice in frame image resolution at fixed data throughput. This paper presents a high-speed stereo vision system that is able to track the golf ball motion at the speed of up to 360 km/h under normal indoor lighting conditions. Binocular camera operated at 810 frames/s with 35- $\mu \text{s}$ exposure time, requiring no additional strobe lights in order not to compromise user experiences. Ball markers were designed for spin measurement. To detect balls and identify markers from highly underexposed low resolution images, new algorithms were developed and implemented on field-programmable gate array board with an advanced RISC machines CPU. The experimental results showed high detection rate and high accuracy with overall processing time less than 300 ms.

In-depth interfacial engineering for efficient indoor organic photovoltaics

Alternative approaches to interlayer optimization are urgently required to realize efficient indoor organic photovoltaics owing to the substantially different indoor light conditions compared to outdoor light conditions (1 sun). In this work, an in-depth study was undertaken on electron-collecting interlayers (ECIs) comprising poly-(ethyleneimine)-ethoxylated (PEIE) modification, zinc oxide (ZnO) nanoparticles (NPs), or a combination of the ZnO NPs and PEIE modification. Morphological, optical, and electrochemical properties of the ECIs were investigated using atomic force microscopy (AFM), ultraviolet-visible (UV–vis) spectrometry, and a Kelvin probe, respectively. Inverted poly(3-hexylthiophene-2,5-diyl):indene-C60 bisadduct (P3HT:ICBA)-OPVs with the ECIs were fabricated. While poor photovoltaic behavior was observed for OPVs with the ZnO NPs owing to the relatively large work function of the ECI under LED light in the absence of UV light, outstanding indoor performance was achieved by OPVs with PEIE modification as the PEIE contributed to work function reduction of the ECI. In particular, OPVs with the ZnO NPs/PEIE ECI yielded the highest efficiencies of up to 14.1 ± 0.3% under 1000-lx LED lamp.

Occupant perception of spectral light content variations due to glazing type and internal finish

Indoor Environmental Quality (IEQ) is a key issue in the design and renovation of any indoor building environment. It is comprised of different aspects (e.g. visual, thermal, acoustic comfort, etc.), which directly affect the building occupants’ wellbeing. Studies on this topic have grown rapidly in recent years, as the time that occupants spend indoors is increasing. In this regard, indoor luminous conditions are crucial for providing sufficient task illuminance as well as to stimulate the human circadian system. Insufficient lighting conditions have been proven to be related with reduced productivity/learnability, mood swings and health disorders, thus emphasizing the necessity for further research in this field. Therefore, proper performance evaluation criteria for managing and optimizing lighting spectral composition is needed. For instance, indoor lighting conditions can be evaluated by quantity, intensity, and/or uniformity, but also by spectral content, which determines the energy conveyed and the level at which the human body is stimulated. This spectral content can vary depending on the preferred or prevalent light source, interior finishes and glazing properties generating a singular indoor lighting environment. Thus, a preliminary study on the variation of the indoor daylight spectral content is conducted using a scaled model, applying various glazing types and interior finishes. Then, daylight simulations are performed on a calibrated virtual model to evaluate the effect of various environmental conditions. Results show a considerable impact of the interior finishes as well as glazing type on the attained circadian potential of studied indoor environment.

The Crucial Role of Quaternary Mixtures of Active Layer in Organic Indoor Solar Cells

A bulk heterojunction (BHJ) consisting of more than one donor/acceptor is one plausible way to improve the charge transport and/or the spectral absorption range in organic solar cells. Ternary and quaternary solar cells have shown promise in this regard. However, quaternary structures have not yet been intensively tested under indoor lighting conditions. A finite-difference time-domain (FDTD)-based simulation was used to solve for the electric field intensity distribution inside a quaternary photovoltaic device illuminated by 500 lx indoor white light emitting diodes (LEDs). We found that quaternary indoor photovoltaics (IPVs) showed peculiarly high oscillations in the simulated ideal short-circuit current density (Jsc,ideal). Here, we simulated the electric field intensity inside the photovoltaic, compared it to single BHJ photovoltaics, and deduced that the electric field intensity inside the active layer of the IPV was highly sensitive to its thickness due to interference between the incident light and the light reflecting from the back electrode. We also found that Poly[N-9′-hepta-decanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) acted as the primary light absorber in the quaternary blend while poly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl}) (PTB7) acted primarily as a cascade energy level and secondarily as a supplementary light absorber.

Tailoring Opto-electrical properties of ultra-thin indium tin oxide films via filament doping: Application as a transparent cathode for indoor organic photovoltaics

Either side of organic photovoltaics incorporates a transparent conducting electrode for light entry, which becomes particularly crucial under indoor light conditions with low light intensity. However, since electrical resistivity and optical transparency with respect to film thickness are mutually contradictory, sufficiently thick (>150 nm) electrodes are inevitably required to ensure the appropriate electrical conductivity, at the sacrifice of transmittance. This paper introduces an electric field induced filament doping method to realize ultra-thin indium tin oxide with high conductivity. The proposed method allows for injecting metal dopants (i.e., Ni) into ultra-thin indium tin oxide under an electric field, enabling substantial resistance reduction while retaining high transmittance and low surface roughness. Optimum light absorption and effective carrier transport via filament doping provides improved performance for indoor organic photovoltaics. As a proof-of-principle demonstration, we fabricate poly(3-hexylthiophene):indene-C60 bisadduct based inverted organic photovoltaics with 10 nm Ni-doped indium tin oxide as a transparent cathode, leading to a power conversion efficiency of 14.6 ± 1.8% under the 1000-lux light-emitting diode. This efficiency is 40% higher than that achieved from the device using commercially available 150 nm indium tin oxide.

Staphylococcus aureus resists UVA at low irradiance but succumbs in the presence of TiO2 photocatalytic coatings

The aim of this study was to evaluate the bactericidal effect of reactive oxygen species (ROS) generated upon irradiation of photocatalytic TiO2 surface coatings using low levels of UVA and the consequent killing of Staphylococcus aureus. The role of intracellular enzymes catalase and superoxide dismutase in protecting the bacteria was investigated using mutant strains. Differences were observed in the intracellular oxidative stress response and viability of S. aureus upon exposure to UVA; these were found to be dependent on the level of irradiance and not the total UVA dose. The wild type bacteria were able to survive almost indefinitely in the absence of the coatings at low UVA irradiance (LI, 1 mW/cm2), whereas in the presence of TiO2 coatings, no viable bacteria were measurable after 24 h of exposure. At LI, the lethality of the photocatalytic effect due to the TiO2 surface coatings was correlated with high intracellular oxidative stress levels. The wild type strain was found to be more resistant to UVA at HI compared with an identical dose at LI in the presence of the TiO2 coatings. The UVA-irradiated titania operates by a “stealth” mechanism at low UVA irradiance, generating low levels of extracellular lethal ROS against which the bacteria are defenceless because the low light level fails to induce the oxidative stress defence mechanism of the bacteria. These results are encouraging for the deployment of antibacterial titania surface coatings wherever it is desirable to reduce the environmental bacterial burden under typical indoor lighting conditions.

High-Performance Organic Energy-Harvesting Devices and Modules for Self-Sustainable Power Generation under Ambient Indoor Lighting Environments.

Organic photovoltaics (OPVs) that perform more efficiently under artificial indoor lighting conditions than they do under sunlight are attracting growing interest as they can potentially serve as ambient energy harvesters for powering low-power electronics and portable devices for the Internet of Things. Herein, solution-processed small-molecule OPVs are demonstrated to exhibit high power conversion efficiencies exceeding 16% under white LED illumination, delivering high output power densities of up to 12.4 and 65.3 μW cm-2 at 200 and 1000 lx, respectively. Increasing the open-circuit voltage ( Voc) of OPVs is a critical factor for achieving higher indoor photovoltaic performance. Toward real applications, this small-molecule OPV system is adopted to fabricate six series-connected modules with an active area of ∼10 cm2 that are capable of generating a high output power surpassing 100 μW and a high Voc of over 4.2 V even under dimly lit indoor conditions of 200 lx. These results indicate that OPVs are promising as indoor electric power sources for self-sustainable electronic devices.

Effects of acetylacetone on the thermal and photochemical conversion of benzoquinone in aqueous solution

Quinones are components of electron transport chains in photosynthesis and respiration. Acetylacetone (AA), structurally similar to benzoquinone (BQ) for the presence of two identical carbonyl groups, has been reported as a quinone-like electron shuttle. Both BQ and AA are important chemicals in the aquatic environment. However, little information is known about their interactions if co-existed. We found here that AA significantly enhanced the conversion of BQ. By analyzing the evolution of chemical concentration, solution pH, dissolved oxygen, and the final products, the interactions between AA and BQ were elucidated. The reactions between BQ and AA generated oxygen but ultimately led to the reduction of solution pH and dissolved oxygen. The reactions proceeded faster under indoor lighting condition than in the dark. The formation of semiquinone radicals is believed as the primary step. The secondary AA-derived radicals might be strongly oxidative or reductive, depending on the concentration of dissolved oxygen. Insoluble humus was generated in the mixture of BQ and AA. These results suggest that the presence of AA might interfere with photosynthesis and respiration through the interactions with quinones.