Upconversion Effect Research Articles

Design and Analysis of an O+E-Band Hybrid Optical Amplifier for CWDM Systems.

Broadband amplification in the O+E-band is very desirable nowadays as a way of coping with increasing bandwidth demands. The main issue with doped fiber amplifiers working in this band such as the bismuth-doped fiber amplifier is that they are costly and not widely available. Therefore, a wideband and flat-gain hybrid optical amplifier (HOA) covering the O+E-band based on a parallel combination of a praseodymium-doped fiber amplifier (PDFA) and a semiconductor optical amplifier (SOA) is proposed and demonstrated through numerical simulations. The praseodymium-doped fiber (PDF) core is pumped using a laser diode with a power of 500 mW that is centered at a wavelength of 1030 nm. The SOA is driven by an injection current of 60 mA. The performance of the HOA is analyzed by the optimization of various parameters such as the PDF length, Pr3+ concentration, pump wavelength, and injection current. A flat average gain of 24 dB with a flatness of 1 dB and an output power of 9.6 dBm is observed over a wavelength range of 1270-1450 nm. The noise figure (NF) varies from a minimum of 4 dB to a maximum of 5.9 dB for a signal power of 0 dBm. A gain reduction of around 4 dB is observed for an O-band signal at a wavelength of 1290 nm by considering the up-conversion effect. The transmission performance of the designed HOA as a pre-amplifier is evaluated based on the bit-error rate (BER) analysis for a coarse wavelength-division multiplexing (CWDM) system of eight on-off keying (OOK)-modulated channels, each having a data rate of 10 Gbps. An error-free transmission over 60 km of standard single-mode fiber (SMF) is achieved for different data rates of 5 Gbps, 7.5 Gbps, and 10 Gbps.

Encapsulation of in-situ generated g-CNQDs with up-conversion effect in Zr/Ti-based porphyrin MOFs for efficient photocatalytic hydrogen production and NO removal

In this study, a highly efficient bifunctional porphyrin-based MOFs with uniformly in-situ generated g-C3N4 quantum dots (g-CNQDs) was fabricated for photocatalytic hydrogen evolution and NO removal, in which PtTCPP as the organic ligand and mixed Zr/Ti-oxo clusters as the metal nodes. Compared with most reported Zr-based porphyrin MOFs, the g-CNQDs@Zr-MOFs(Pt)(Zr/Ti) exhibited outstanding hydrogen evolution activity (14511.57 μmol g−1) and NO removal rate (31.9 %) under visible light irradiation. The obviously improved photocatalytic performance could be attributed to the significantly enhanced charge separation and transfer rates by the mixed Zr/Ti-oxo clusters via the rapid Ti3+/Ti4+ process. Moreover, the uniformly in-situ generated g-CNQDs via confinement effect in the cavity of MOFs could also improve the utilization of visible light especially through the up-conversion effect, and promote charge carriers separation. This work provides an idea for us to expand the scope of light utilization and promote charge transfer and separation rates of MOFs via functionalizing host MOFs matrix and coupling guest active species to improve photocatalytic performance further.

Investigation of quantum dots light emitting diodes with different transition metal oxide as charge injection layers

In this paper, various transition metal oxides serve as charge injection layers being prepared by solution process for the fabrication of quantum dot light emitting diodes (QLEDs) is demonstrated. Magnesium doped zinc oxide (MgZnO) nanoparticles is used as electron injection and transport layer, copper oxide (CuO x ), nickel oxide (NiO x ), cobalt oxide (CoO x ) and molybdenum oxide (MoO x ) are used as hole injection layer (HIL) for the comparison with Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate), PEDOT:PSS. The fabricated red QLEDs with PEDOT:PSS possess highest maximum luminance of 88,713 cd/m 2 and current efficiency of 4.96 cd/A, whereas QLEDs with MoO x and NiO x HILs demonstrate lower turn on voltage of 1.5V and 2.1V and maintain decent maximum luminance of 59,699 and 64,244 cd/m 2 , respectively. The sub-bandgap turn-on voltage of QLED with MoO x can be attributed to thermal-assisted energy up-conversion effect due to its lower series resistance. • Various solution process metal oxides are used as QLEDs charge injection layers. • QLEDs with NiO x and MoO x HILs demonstrate lower turn on and forward voltage. • MoO x device achieve a sub-bandgap turn-on voltage of 1.5 V for red QLEDs.

Synergistic effect of upconversion, plasmonic and semiconducting properties of ternary nanocomposites for photocatalytic application under different light regions

The design of the efficient photocatalytic system with extended absorption of the broadband spectrum is the need of the hour. The synergistic effect of upconversion, plasmonic and semiconducting materials can significantly enhance the broadband absorption, and effective separation and transfer of charge carrier. In this work, a novel ternary plasmonic photocatalyst consisting of NaY0.5Gd0.5F4:Yb/Tm@NaYb0.5Gd0.5F4 core@shell (UCP), Au nanoparticles (Au NP) and N-ZnO has been prepared via hydrothermal synthesis route. The prepared nanocomposites are capable of harnessing ultraviolet (UV), visible (VIS) and near-infrared (NIR) light. The work specifically deals with the utilization of these ternary nanocomposites for photocatalytic elimination of tetracycline under UV, VIS and NIR light irradiations. The improved photocatalytic activity of the ternary plasmonic photocatalyst can be ascribed to the synergistic effect of all the components arranged systematically that favours harnessing of broadband spectrum for effective activation of charge carriers. Moreover, rational design and development of the UCNP/Au/N-ZnO photocatalyst shall pave the way for the fabrication of broadband absorption plasmonic photocatalysis.

Columnar cactus-like 2D/1D BiOBr/BiVO4:Yb3+,Er3+ heterostructure photocatalyst with ultraviolet-visible-near infrared response for photocatalytic degrading dyes, endocrine disruptors and antibiotics

An innovative strategy for the integration of the upconversion (UC) effect with a Z-scheme heterojunction is proposed to develop photocatalysts to achieve high carrier separation efficiency and efficient utilization of broadband solar spectra in this work. By the above strategy, novel and columnar cactus-like BiOBr/BiVO4:Yb3+,Er3+ heterostructured nanobelts with an efficient full-spectrum light response are synthesized by electrospinning combined with a solvothermal method and are composed of two-dimensional (2D) BiOBr nanosheets modified on the surface of one-dimensional (1D) BiVO4:Yb3+,Er3+ nanobelts. The optimized BiOBr/BiVO4:Yb3+,Er3+ heterostructured nanobelts exhibit superior photocatalytic activity for degrading 89.2 % tetracycline hydrochloride (TCH, 60 min), 89.8 % bisphenol A (BPA, 180 min) and 95.9 % methylene blue (MB, 120 min) under simulated sunlight irradiation as well as 72.3 % TCH, 24.6 % BPA and 69.7 % MB under 12 h near infrared (NIR) light irradiation. The excellent photocatalytic activity can be ascribed to the synergistic effect among the porous structure of nanobelts for producing a large number of surface active sites, broadening of spectral response range by the remarkable upconversion effect, unique 2D/1D contact interface for fast carrier transfer channel and built-in electric field induced by Z-scheme heterojunction as well as Yb3+/Yb2+ redox center for spatial separation of photogenerated carriers. In addition, the photocatalyst exhibits superior reusability and recycling stability in photocatalytic applications. This work not only puts forward the innovative idea of constructing an efficient broad-spectrum photocatalyst for water purification but also provides key technical guidance for the morphology control of high-efficiency photocatalysts.

Novel Co2+ passivated carbon nanodots with up-conversion effects combined with NH2-MIL-125 for improving photocatalytic NO purification and hydrogen evolution

Novel ionic state Co passivated carbon nanodots (Co-CDs) combined with NH2-MIL-125 as efficient photocatalysts Co-CDs/NH2-MIL-125 were fabricated in a convenient process for the first time. These materials exhibited excellent photocatalytic activity in both NO purification and hydrogen production under visible light irradiation. The NO purification rate of Co-CDs/NH2-MIL-125 increased to 46.6%, which was 20.2% and 13.4% higher than that of NH2-MIL-125 and CDs/NH2-MIL-125, respectively. Moreover, the hydrogen production efficiency of Co-CDs/NH2-MIL-125 reached 2261 μmol g−1, which was 6.86 times and 3.54 times of the values for NH2-MIL-125 and CDs/NH2-MIL-125, respectively. The corresponding properties characterized by Mott-Schottky, UCPL, and in situ DRIFTS, indicated that the introduction of Co2+ could not only passivate the CDs to further improve physicochemical properties, but also enhance the photocatalytic activity via the photosensitization and up-conversion effect. This research provides a promising strategy that adding active metal ions passivated CDs in the catalyst platform to improve photocatalytic performance.

Fabrication of Er3+/Yb3+ co-doped NiAl-LDH with promoted photocatalytic performance for CO2 reduction under Vis/NIR light irradiation

In this study, Er3+/Yb3+ co-doped NiAl-LDH (LDH:Er3+,Yb3+) photocatalysts were successfully fabricated through a solvothermal process. The results revealed that the LDH:Er3+,Yb3+ displayed promoted photoreduction CO2 activity under Vis/NIR light irradiation. A maximum CO yield of 13.2 μmolg−1h−1 had been obtained on LDH:1%Er,2%Yb, which was 9.4 and 1.5 times higher as high as the pure LDH and the LDH:1%Er, respectively. The improved photocatalytic activity can be ascribed to the expanded photoresponse range to NIR light region caused by the upconversion effect of Er3+/Yb3+, and the improved photogenerated charge separation efficiency with Er3+/Yb3+ serving as an electron trap. The NIR photocatalytic activity and the improved light absorption of LDH: Er3+,Yb3+ indicate that the upconversion mechanism is involved in the whole photocatalytic process. Therefore, this result presents new insights for the rational construction of Vis-NIR light-driven photocatalysts with high-efficient solar energy utilization and practical application prospects in the future.

Strategies for high‐performance perovskite solar cells from materials, film engineering to carrier dynamics and photon management

AbstractIn recent years, halide perovskite solar cells (HPSCs) have attracted a great attention due to their superior photoelectric performance and the low‐cost of processing their quality films. In order to commercialize HPSCs, the researchers are focusing on developing high‐performance HPSCs. Many strategies have been reported to increase the power conversion efficiency and the long‐term stability of HPSCs over the past decade. Herein, we review the latest efforts and the chemical‐physical principles for preparing high‐efficiency and long‐term stability HPSCs in particular, concentrating on the perovskite materials, technologies for perovskite films, charge transport materials and ferroelectric effect to reduce the carrier loss, and photon management via plasmonic and upconversion effects. Finally, the key issues for future researches of HPSCs are also discussed with regard to the requirements in practical application.image

High-performance diode-end-pumped Nd:YLF laser operating at 1314 nm.

A stable, efficient, and powerful 1314 nm Nd:YLF laser inband-pumped by a wavelength-locked narrowband 880 nm laser diode is demonstrated. The influence of mode-to-pump ratio on the performance of the diode-end-pumped Nd:YLF laser has been systematically investigated by taking into account the thermal effect and the energy transfer upconversion effect. For the optimum mode-to-pump ratio of 0.84, the maximum continuous wave output power of 21.9 W was extracted under the pump power of 70 W, which corresponded to the optical power efficiency of 31.3% and the beam quality of M2 ≈ 1.6. The resultant output power stability was determined to be 0.059% (RMS) within 1 h. In addition, by increasing the mode-to-pump ratio to 1.0, the near-diffraction-limited beam (M2 ≈ 1.3) was achieved with the output power of 17.0 W and the optical power efficiency of 24.3%.

A synergistic effect of NaYF4:Yb,Er@NaGdF4:Nd@SiO2 upconversion nanoparticles and TiO2 hollow spheres to enhance photovoltaic performance of dye-sensitized solar cells

Introducing upconversion nanoparticles (UCNPs) or fabricating TiO2 hollow spheres (TiO2-HSs) are considered two feasible strategies to enhance the photovoltaic performance of dye-sensitized solar cells (DSSCs). However, studies investigating a combination of UCNPs and TiO2-HSs for the application in DSSCs are still scarce. In this contribution, NaYF4:Yb,Er@NaGdF4:Nd@SiO2 UCNPs and TiO2-HSs were synthesized and respectively applied as upconversion layers and scattering layers on the TiO2 photoanode of DSSCs. The influence of different doping ratios of UCNPs on cell performance was explored. The present results reveal that the DSSCs device based on conventional P25 photoanode films incorporating the UCNPs with 10% can achieve a photovoltaic efficiency of 6.65%, showing 29.63% enhancement in comparison to the device without UCNPs. When the TiO2-HSs are used as scattering layers above the P25 film, the DSSCs device obtains a higher photovoltaic efficiency of 6.97%. More importantly, combining the UCNPs and TiO2-HSs can further enhance the photoelectrical property of DSSCs, realizing an optimal efficiency of 8.17%. Such an improvement can be attributed to a synergistic mechanism arising from the upconversion effect of UCNPs and the light scattering effect of TiO2-HSs. This work opens a new way of preparing composite photoanode films to improve the photovoltaic performances of DSSCs.

In-situ one-step synthesis of porous monolayer carbon nitride nanosheets doped with carbon quantum dots for photocatalytic degradation of Meloxicam

The energy storage and upconversion effect of carbon quantum dots (CQDs) could improve the photocatalytic efficiency of materials. In this study, a visible-light-driven photocatalyst, CQDs-doped carbon nitride nanosheets composite (CNS/CQDs) was in-situ synthesized by the thermal stripping of carbon nitride bulk (CNB). The as-prepared CNS/CQDs photocatalyst was systematically characterized and applied to the removal of Meloxicam (Mel) in water. The results showed that the introduction of CQDs could improve the visible light utilization of the carbon nitride. Mel (50 mL, 10 mg L−1) was degraded by 99.60% in 45 min with CNS/CQDs (20 mg). The stability and recycling experiments showed that CNS/CQDs could maintain high photocatalytic activity under complex matrix and multiple cycles. This work will provide a new attempt to synthesize the CQDs doped photocatalytic materials for the effective removal of organic pollutants in water under visible light.

A Gyroscope Nanogenerator with Frequency Up-Conversion Effect for Fitness and Energy Harvesting.

Converting the mechanical energy of human motion into electricity is considered an ideal energy supply solution for portable electronics. However, low-frequency human movement limits conversion efficiency of conventional energy harvesting devices, which is difficult to provide sustainable power for portable electronic devices. Herein, a fitness gyroscope nanogenerator (fg-NG) based on a triboelectric nanogenerator (TENG) and electromagnetic generator (EMG) is developed that can convert low-frequency wrist motion into high-frequency rotation by using the frequency up-conversion effect of the gyroscope. Remarkably, the fg-NG can reach a rotational speed of over 8000rpm by hand, increasing the frequency by more than 280 times. The fg-NG can continuously and stably output a current of 17mA and a voltage of 70V at frequency of 220-230Hz. The fg-NG is demonstrated to consistently power a hygrothermograph, smart bracelet, and mobile phone. Also, it can be applicated to a self-powered intelligent training system, showing its immense application potential in portable electronics and wireless Internet of Things devices.

Performance Enhancement of Praseodymium Doped Fiber Amplifiers

In this paper, we report a simulation study on the performance enhancement of Praseodymium doped silica fiber amplifiers (PDFAs) in O-band (1270–1350 nm) in terms of small signal gain, power conversion efficiency (PCE), and output optical power by employing bidirectional pumping. The PDFA performance is examined by optimizing the length of Praseodymium doped silica fiber (PDF), its mode-field diameter (MFD) and the concentration of Pr3+. A small-signal peak gain of 56.4 dB, power conversion efficiency (PCE) of 47%, and output optical power of around 1.6 W (32 dBm) is observed at optimized parameters for input signal wavelength of 1310 nm. Minimum noise figure (NF) of 4.1 dB is observed at input signal wavelength of 1310 nm. Moreover, the effect of varying the pump wavelength and pump power on output optical power of the amplifier and amplified spontaneous emission (ASE) noise is also investigated, respectively. Finally, the impact of ion-ion interaction (up-conversion effect) on small-signal gain of the amplifier is also studied by considering different values of up-conversion coefficient.

Effects of frequency upconversion layer and two-dimensional arrays of inverted nanocone hole on the performance of ultrathin crystalline silicon solar cells

We report the design and optimization of photonic crystal (PhC) structures within the crystalline silicon absorption layer in ultrathin solar cells with a frequency upconversion layer. In the PhC structure, inverted nanocone hole (ICH) arrays with different diameters and inclination angles are used, and the light-trapping performances of air and Si3N4 filled ICH arrays are systematically studied by COMSOL Multiphysics, respectively. The simulation results indicate that the average optical absorption of the solar cells and the local electric field intensity in the upconversion layer can be greatly improved by using PhC structures within the absorption layer. For ICH in height of 1.6 μm, the maximum absorptivity of the solar cells with air filled ICH arrays is 90.75%, while the maximum absorptivity of solar cells with Si3N4 filled ICH arrays is 85.62%. In addition, the upconversion effects of β-NaYF4:Er3+/Yb3+ nanomaterials on the power conversion efficiency of the solar cells were also investigated. The presented model will be the basis for further preparations of high-efficiency ultrathin crystalline silicon solar cells.

Collectively Exhaustive Hybrid Triboelectric Nanogenerator Based on Flow‐Induced Impacting‐Sliding Cylinder for Ocean Energy Harvesting

AbstractFor the sustainable application of remote sensing and monitoring in the ocean environment, energy harvesting technology based on flow‐induced vibration is in the spotlight. Herein, based on the flow‐induced self‐excitation of an impacting‐sliding cylinder, a collectively exhaustive hybrid triboelectric nanogenerator (TENG) is reported, that utilizes both freestanding‐sliding (FS) and contact‐separation (CS) modes. Most importantly, the flow‐induced impacting cylinder (FIC) between two side walls is newly implemented to resolve the critical problem of the lock‐in phenomena occurring in conventional vortex‐induced vibration systems of circular cylinders. Owing to the presence of two side walls, the FIC based TENG (FIC‐TENG) shows a stable electrical power generation in a wide range of flow velocity (0.05–1.02 m s−1) without lock‐in phenomena. In addition, the collectively exhaustive FIC‐TENG can be used to continuously produce electric power utilizing both FS and CS hybrid modes. The energy harvesting performance is greatly enhanced by adopting nanopatterns on triboelectric surfaces in the CS mode TENG and a frequency upconversion effect of interdigitated electrodes in the FS mode TENG, resulting in proper remote operation of a wireless fidelity thermometer.

Flash Synthesis of DNA Hydrogel via Supramacromolecular Assembly of DNA Chains and Upconversion Nanoparticles for Cell Engineering

AbstractDeoxyribonucleic acid (DNA) hydrogel has been synthesized generally via the molecular interaction of either DNA base‐pairing, covalent bonding, or physical entanglement. To surmount the limitations of DNA as the sole module in materials, new assembly modes are desired to incorporate to expand the functionalities of DNA hydrogel. Herein, a supramacromolecular assembly‐based strategy is reported to prepare a hybrid DNA hydrogel via interfacial assembly of DNA chains and upconversion nanoparticles (UCNPs), remarkably of which the synthesis process finished within one second, termed as flash synthesis. The flash synthesis is accomplished through the electrostatic attraction, interfacial assembly, and cross‐linking of DNA chains on the surface of UCNPs. The length of DNA and the crystalline form of UCNPs are proven to be essential factors in the construction of a hydrogel network. The rationally designed DNA endowed hydrogel with functions to precisely recognize and isolate specific cells, and lanthanide ions‐doped UCNPs protected cells from the damage of near‐infrared irradiation through the upconversion effect. It is envisioned that the flash synthesis provides a new mode to prepare the DNA hydrogel and expands the functionalities to realize more real‐world applications.

Unveiling the origin of performance enhancement of photovoltaic devices by upconversion nanoparticles

To better utilize the infrared (IR) region in sunlight for photovoltaic devices (PVs), upconversion nanoparticles (UCNPs) have been proposed to improve power conversion efficiency (PCE). However, researchers recently have found that the upconversion (UC) effect is negligible in PVs performance improvement for their ultra-low UC photoluminescence quantum yields of UCNPs solid film, while the real mechanism of UCNPs in PVs has not been clearly studied. Herein, based on the material inorganic perovskites γ-CsPbI3, NaYF4:20%Yb3+,2%Er3+ UCNPs were integrated into different transport layer to optimize device performance. Compared with reference device, the short-circuit current density and PCE of optimized device reached 20.87 mA/cm2 (20.39 mA/cm2) and 18.34% (17.72%), respectively, without sacrificing open-circuit voltage and filling factor. Further experimental characterizations verified that the improved performance was attributable to enhanced visible light absorption instead of IR. To theoretically explain the statement, the light field distribution in device was simulated and the absorption in different layers was calculated. The results revealed that the introduction of UCNPs with different refractive index from other layers caused light field disturbance, and improved visible light captured by γ-CsPbI3. Importantly, through experiments and theoretical calculation, the research deeply explored the potential mechanism of UCNPs in optimizing PVs performance..

Carbon dot-coupled BiVO4/reduced graphene hydrogel for significant enhancement of photocatalytic activity: Antibiotic degradation and CO2 reduction

In this study, we fabricated a novel hybrid photocatalyst (CD-BVO/rGH) by coupling carbon dot (CD)-decorated BiVO4 (BVO) with a reduced graphene hydrogel (rGH). The CD-BVO/rGH photocatalyst significantly enhanced the photocatalytic efficiency for tetracycline hydrochloride (TCH) degradation compared with pure BVO and BVO/rGH under simulated solar irradiation. CD-BVO/rGH also showed a substantial performance in the photocatalytic reduction of CO2. The enhanced photocatalytic activity of CD-BVO/rGH is attributed to synergistic effects, such as better light energy utilization via the upconversion effects of the CDs and the enhanced migration and separation of photoexcited carriers by the three-dimensional (3D) network structure of the rGH. The systematic analysis of the band structure, electron spin resonance, and free radical trapping revealed that h+ and O2– mediate the final photocatalytic degradation of pollutants. Our results provide insight into the design and construction of highly efficient hybrid photocatalysts combined with functional carbon nanostructures to enhance the photocatalytic activity for the photodegradation of environmental pollutants and CO2 reduction.

Strategic combination of nitrogen-doped carbon quantum dots and g-C3N4: Efficient photocatalytic peroxydisulfate for the degradation of tetracycline hydrochloride and mechanism insight

• N-CQDs/g-C 3 N 4 /PDS photocatalytic system was firstly used for HTC degradation. • N-CQDs/g-C 3 N 4 efficiently activated PDS under visible-light irradiation. • Excellent charge separation efficiency can be obtained due to N-CQDs and PDS. • •SO 4 − , O 2 − and h + were found as the dominant contributors to the HTC degradation. • The mechanism of N-CQDs/g-C 3 N 4 /PDS photocatalytic system was proposed. Photo-assisted peroxydisulfate (PDS) activation has exhibited a great potential for pollution control. In this study, metal-free nitrogen-doped carbon quantum dots (N-CQDs) modified g-C 3 N 4 composite was fabricated and used to activate PDS under visible light to effectively remove tetracycline hydrochloride (HTC) in wastewater. Specifically, almost 90% of HTC (20 mg/L) was removed in 60 min under the conditions of an initial value of catalysis dose of 0.5 g/L and PDS dose of 0.6 g/L. Electron spin resonance analysis and trapping experiments confirmed that SO 4 − , O 2 − and h + were found as the dominant contributors to the HTC degradation. PDS and N-CQDs acted as an electron acceptor to transfer the photogenerated charges, resulting in the successful activation of PDS. The promoting visible light absorption can be ascribed to up-conversion effect of N-CQDs. The combination strategy provides an innovative approach to synthesize binary metal-free carbonaceous photocatalysts for implementing PDS-based oxidative degradation of pollutants.

Fast electron transfer and enhanced visible light photocatalytic activity of silver and Ag2O co-doped titanium dioxide with the doping of electron mediator for removing gaseous toluene

Volatile organic compounds (VOCs) can influence air quality and threaten human health; however, the development of an effective method to remediate toxic VOCs is still remain challenge. Herein, a novel silver and Ag2O co-doped TiO2 with fast electron transfer modified by nitrogen doping carbon dots was prepared via a facile chemical precipitation-reduction method. Under 50 min of visible light irradiation, the novel photocatalyst exhibited approximately 50% gaseous toluene degradation efficiency, which was ca. 9.7 times and 2.2 times higher than that of bare TiO2 and silver and Ag2O co-doped TiO2, respectively. Importantly, the photocatalyst also showed a stable structure and good recycling ability after 400 min of photocatalytic degradation with little amount of NCDs. Besides, the up-conversion effect of NCDs could emit high-energetic light and thus generate more e−-h+ pairs, which could facilitate the SPR effect of Ag and thus showed strong visible light response because of the localized surface plasmon resonance (LSPR) excitation. Thus, the excellent photocatalytic performance could attribute to the synergetic effect of up-conversion effect of NCDs and SPR effect of silver which could both facilitate charge carriers separation and improve visible-light response. Finally, a possible mechanism for the excellent photocatalytic activity was proposed, in which the active species including ·O2−, ·OH and h+ were generated and contributed to photocatalytic process. The successful fabrication of DACT provides a potential strategy for the treatment of VOCs in practical applications.