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Here, we firstly propose an A-site engineering strategy to improve the luminescence performance of Cs3Cu2I5. Through the incorporation of FA+, the lattice defects in Cs3Cu2I5 can be reduced and the PLQY of the optimized sample is increased to 95%.

High-quality CsPbBr3 QDs were regulated to be precipitated in borosilicate glass by introducing a network modifier, CaF2, and the roles of Ca ions and F ions on the nucleation/growth of CsPbBr3 QDs in glass were revealed.

A narrow band and stable CsPbBr3 light converter was elaborately designed for laser-driven projection displays.

This fluorescent sensing material has the excellent optical properties of g-CDs and the selective detection and adsorption capability of UiO-66 for the target analyte; it determines the norfloxacin concentration via the F432/F530 fluorescence ratio.

The desired dynamic spectra of plants can be achieved by placing PSC light convertors with different light qualities on blue LED chips.

Both perovskites and organic semiconductors are promising candidates for next-generation portable and wearable photodetectors (PDs), owing to their facile solution processibility and remarkable optoelectronic features. In recent years, there has been growing interest in combining the two and constructing perovskite/organic hybrid PDs, which are demonstrated to present a broad photoresponse spectrum, high photoresponsivity and good environmental stability. Since great progress has already been made, a comprehensive summary would be very important for this field. However, this is still lacking. In this review, we provide a thorough progress report and in-depth discussion on the perovskite/organic hybrid PDs, from the very fundamental device operation principles to advanced design strategies. Firstly, the main parameters of the PD devices are introduced. Then, the developments of the perovskite/organic hybrid PDs, including photodiodes, photoconductors and phototransistors, are discussed in detail. Finally, current challenges are summarized and potential solutions are proposed.

Random resistive access memory (RRAM) devices with a simple structure, low power consumption, and tunable switching behavior have emerged as promising candidates to simulate biological synapses. Here, we demonstrate solution-processable RRAM devices with FeC–rGO nanocomposites by intercalating nano-aggregating ferrocenes (FeCs) between the reduced graphene oxide (rGO) sheets, in which FeCs anchor on the surface of rGO through π–π stacking interactions. The Al/FeC–rGO/ITO devices fabricated by spin-coating exhibit a low SET/RESET voltage of −1.7 V/+2.1 V and a high ON/OFF ratio of 108, which results from the formation/rupture of conductive paths between rGO sheets gated by the redox of FeCs. Besides, the devices show high repeatability, excellent durability and favorable flexibility. In addition, the obtained device can be utilized to simulate the potentiation and depression of synapses by applying a pulse voltage below VSET, further contributing to image pattern recognition. Thus, this approach aims to fabricate information storage devices for future use in artificial intelligence.

Embedding CsPbBr3 quantum dots (QDs) in inorganic glasses via in situ crystallization has been regarded as a feasible strategy to improve their stability due to the protecting role of the robust glass matrix. However, the influence of the rigidity of the glass network structure on CsPbBr3 crystallization is rarely reported. Herein, we report an approach to control the rigidity of the glass network structure through substituting the [GeO4] tetrahedron with the [SiO4] tetrahedron in mother glass, which allows fine-tuning of the morphology and luminescence properties of CsPbBr3 QDs. The water-resistance of CsPbBr3 QD glass (CsPbBr3 QD@glass) is clearly enhanced by increasing the content of the [SiO4] tetrahedron, while the size of CsPbBr3 nanocrystals decreases gradually and the corresponding quantum efficiency decreases. Moreover, the thermostability and photostability of CsPbBr3 QD@glasses were also studied systematically. The correlation between the rigidity of the glass network structure and the local microenvironment of the crystallization of CsPbBr3 QDs is revealed. Our results provide a reference for the design of mother glass to obtain perovskite QDs with high quantum efficiency and high stability based on the rigidity of the glass network.

A series of novel hyper-structured molecular (HSM) thermally activated delayed fluorescent (TADF) emitters, in which the TADF units and host units are bound together into one inactive core through flexible linkages, were designed. Phenoxazine-triphenyltriazine (PXZ-Trz), 1,3-bis(9H-carbazol-9-yl)benzene (mCP) and calix[4]resorcinarene (CRA) were chosen as the TADF unit, the host unit and the core, respectively. A series of CRA-based HSM emitters, CRA-PXZ-Trz(X)-mCP(100−X) (X = 0, 12.5, 25, 50, 75, 87.5 or 100) were successfully synthesized by a two-step click reaction. Upon using non-doped CRA-PXZ-Trz(87.5)-mCP(12.5) as the light-emitting layer, the solution-processable OLEDs emitted yellow-green light, and displayed an external quantum efficiency of 16.7% at 100 cd m−2.

The fiber-shaped resistive random access memory (RRAM) is an important subject for flexible wearable electronic textiles. The investigation of the resistive switching (RS) performance of the materials in the basic storage unit (crosspoint) of a flexible fibrous crossbar is very significant for realizing flexible wearable memories. In this work, fibrous crosspoint RRAM devices, abbreviated as FCPe-RRAMs, have been fabricated on the basis of organic–inorganic halide perovskite MAPbI3. Herein, a functional Al@MAPbI3 fiber is first prepared via a simple dip-coating method, in which the low-temperature solution processing method and cheap raw materials are conducive to the future large-scale and low-cost production. By optimizing the preparation conditions for MAPbI3, a pinhole-free, compact and uniform perovskite film is deposited on the bare Al fiber. Then, the FCPe-RRAM devices with a configuration of Al@MAPbI3/Al are assembled on a homemade holder by perpendicularly crossing the bare Al fiber and the functional Al@MAPbI3 fiber at a certain bending angle. The FCPe-RRAM devices exhibit a bipolar RS behaviour. The highest ON/OFF ratio reaches up to approximately 106 in the FCPe-RRAM devices, together with a low SET/RESET voltage (+1.66 V/−0.47 V) and a long retention time (>104 s). The FCPe-RRAM devices also exhibit excellent reproducibility and operational uniformity, which are important for practical applications in mass production. The investigation of the RS mechanism suggested that the FCPe-RRAM devices follow the mechanism of conductive metallic filament formation by the generated electrons with the help of thermionic emission. This work reveals the potential promising applications of FCPe-RRAM devices in flexible wearable memories with high storage density.

As one of the key elements of indoor agriculture, horticultural light sources are developing rapidly towards requiring high energy density, high output power and high stability, which poses a challenge for traditional phosphor conversion devices. To address this, an all-inorganic blue-red dual-emitting light convertor consisting of Ba1.3Sr1.7MgSi2O8:Eu2+,Mn2+ (BSMS) phosphor-in-glass (PiG) plates was prepared to improve the duration lifetime of converted high-power light-emitting diodes (LEDs) and meet the light quality requirements of photosynthesis for indoor agriculture. The obtained samples show an external quantum efficiency of 45.3%, outstanding thermal stability and a specific emission spectrum that highly matches the absorption of chlorophyll and β-carotene. Moreover, a proof-of-concept BSMS-PiG horticultural lamp for application in an indoor plant factory was successfully fabricated based on a ∼370 nm emitting LED chip. The blue-red ratio of its spectrum could be regulated by controlling the thickness of BSMS-PiG and the concentrations of Mn2+ ions within BSMS-PiG. The BSMS-PiG horticultural LEDs were applied to the indoor cultivation of Romaine lettuce. The results indicated that the biomass of Romaine lettuce was 58.21% greater than that of control lettuce samples cultivated under commercial plant lamps. In particular, the content values of total chlorophyll, β-carotene and soluble protein were improved. The BSMS-PiG horticultural LED is a potential candidate to act as a high-power horticultural light source.

Biogenic amines (BAs) from rotten food cause serious harm to sensitive people. Therefore, the development of a smart label that can intuitively monitor the degree of food decay in real-time is of great significance in food safety. Herein, we report the synthesis of pH-responsive carbon dots with red emission (R-CDs) by the solvothermal treatment of citric acid and urea. The fluorescence intensity of R-CDs gradually increased as the pH of the solution increased from 1 to 12. We studied the mechanisms of pH response and found that H-aggregation occurred when R-CDs were in acidic solution and caused quenching; when they were distributed in alkaline solution, the Fermi level shift caused reduced self-absorption and enhanced red fluorescence emission. The intense red emission of R-CDs is beneficial for the visual detection of alkaline organic amines and BAs derived from rotten shrimp to achieve food safety detection. Moreover, the R-CDs can be used as a promising pH-sensitive fluorescent ink, which has broad prospects and significance in anticounterfeiting and information encryption.

As emerging carbon materials, carbon dots (CDs) have received extensive attention in recent years. Since CDs have excellent optical properties, most reports on carbon dots focus on research of their optical applications. However, their diverse surface functional groups also afford broad application prospects in chemical engineering. This review article focuses on the research progress in the chemical applications of CDs in the following three aspects: CDs used as structural regulators of the morphology and size of materials; CDs used as chemical additives, such as consolidant, antirust, antifreeze, lubricant, and scale inhibitors; CDs used as reinforcing reagents to improve water dispersibility and enhance mechanical properties of materials. Finally, we focus on existing problems in this field and look forward in the direction of future development.

Stimuli-responsive shape-memory materials are a category of fascinating smart materials, which undergo reversible shape transformation with environmental changes. Among a large number of stimuli-responsive shape-memory materials, light-driven materials have sparked tremendous attention because of their stability, remote operability and environmentally friendly. Herein, we report a novel strategy for the synthesis of a light-responsive shape-memory polymer that is made from carbon dots and polyvinyl alcohol. The as-prepared carbon dots are endowed with good visible light absorption and excellent photothermal conversion, which enable the carbon dot/polyvinyl alcohol composite polymer to serve as a light-responsive shape-memory polymer. The carbon dots not only work as photothermal agents but also offer additional hydrogen bond interaction, which accelerates the shape-memory recovery rate. The results show that the composite polymer can realize shape recovery using relatively low laser power. Most importantly, the as-prepared carbon dot/polyvinyl alcohol composite polymer not only possesses great research potential in different types of fields, such as medical and sensing, but also provides a effective and economic strategy for taking the advantage of light.

Afterglow including thermally activated delayed fluorescence (TADF) and room-temperature phosphorescence (RTP) has stimulated considerable attention owing to bright potential applications in optoelectronic devices, sensing, and security systems. However, previously reported afterglow materials are mostly single-mode (one of RTP or TADF only), a tunable multi-mode afterglow emission is still rarely achieved. Herein, we report the temperature-responsive conversion characteristics of TADF and RTP of carbon dots in silica (CDs@SiO2) for the first time. The unique temperature-responsive afterglow characteristics, that is, phosphorescence and TADF can be mutually transformed as the temperature changes, resulting in the free conversion of the RTP/TADF ratio as well as the afterglow color change through simple temperature control. The Si–O network plays multiple roles to strengthen and confine the embedded CDs, thus resulting in ultralong RTP emission and unique afterglow characteristics. Furthermore, CDs@SiO2 exhibited excellent stability against water, acid, alkali, salt and oxidants as well as polar solvents. CDs@SiO2 with unique afterglow characteristics and high stability can have multiple potential applications in rapid fingerprint detection and temperature sensing, especially in advanced temperature-responsive multicolor anti-counterfeiting and encryption.

All-inorganic perovskite CsPbBr3 quantum dots (QDs) are becoming the most popular narrow-band green emitter for use as a critical material in next generation wide-color-gamut backlight displays. However, their intrinsic poor stability greatly hinders their development for practical applications. Herein, CsPbBr3 QDs were successfully precipitated in boro-germanate glass (CsPbBr3 QDs@glass) with well-designed compositions, not only retaining a high photoluminescence quantum yield (PLQY of 43% upon 450 nm excitation) and narrow bandwidth (FWHM of 22 nm), but also showing significantly enhanced stability in relation to water, heat, and UV/blue irradiation. The relative PL intensity of CsPbBr3 QDs@glass was maintained at 60% or 85% after being immersed in water for 22 days or exposed to UV light for 100 hours, respectively. Moreover, CsPbBr3 QDs@glass samples present impressive recovery abilities in thermal cycling experiments or upon intermittent blue light irradiation. Finally, an all-inorganic white light-emitting diode (white LED) achieving 125% of National Television Standards Committee (NTSC) performance was fabricated through employing green-emitting CsPbBr3 QDs@glass and red-emitting Cs2SiF6:Mn4+ phosphor-in-glass (PiG) plates as color convertors. The design rules established here could initiate the further exploration of other glass systems with moderate halide solubilities and low melting temperatures to precipitate highly efficient and stable CsPbX3 (X = Cl, Br, I) QDs.

In this paper, a facile hydrothermal route was proposed to synthesize a bright blue-emitting solution of silicon nanoparticles (s-Si NPs) with a high photoluminescence quantum yield (PLQY) of 66%. And a self-quenching-resistant solid-state fluorescent powder of Si NPs (p-Si NPs) was obtained by freeze drying, which exhibited dual wavelengths with blue and yellow emission peaks. In addition, the blue-band emission of p-Si NPs was ascribed to the graphitizing cores, while the yellow-band emission of p-Si NPs originated from the trapping surface state. Based on this finding, a high temperature calcining strategy was proposed to obtain multicolor Si NP powders by adjusting the surface defects of p-Si NPs for the first time. A series of multicolor Si NP powders with wavelengths from blue to red was obtained by adjusting the calcination time/temperature. Structural and spectroscopic characterizations also proved that the mechanism of their PL red shift was attributed to the oxygen-related surface state, rather than the size effect. Because of their unique multicolor emission, their related multicolor light-emitting diode (LED) devices were obtained to explore their possible application in the field of solid-state lighting. Moreover, SSF-2-based films were fabricated by combining carboxymethyl cellulose (CMC) and SSF-2 powder to explore their potential application as light conversion films (LCFs) in the field of agricultural planting.

A simple sol–gel method was used to integrate carbon dots (CDs) with upconversion (UC) luminescent materials NaYF4:Yb,Er(Tm) to form composites. We found for the first time that the CDs acted as a sub-energy level to mediate energy transfer between different levels of the rare earth ions. Impressively, enhanced red and NIR upconversion emissions were achieved in the NaYF4:Yb,Er(Tm)@CDs composites.

White lighting sources based on laser diodes (LDs) are strongly regarded as the next generation of high luminance lighting sources because the luminous efficiency of LDs increases linearly with operating current, which can resolve the “efficiency droop” of LEDs. To facilitate the advent of high brightness solid state lighting, searching for a light convertor with high thermal stability, high conversion efficiency, and irradiation stability is essential. Herein, we developed a robust light convertor, YAG:Ce3+ based on phosphor-in-glass (denoted as YAG-PiG), exhibiting a quantum efficiency of 70.1% and a high thermal conductivity of 0.89 W m−1 K−1. The microstructure and luminescent properties of YAG-PiG were also investigated in detail. Compared to YAG-PiS (phosphor-in-silicone), this YAG-PiG shows an overall increase in irradiation and thermal stability performances. A high power white LDs was constructed by coupling the YAG-PiG with a 445 nm blue laser and a sapphire plate modified by an antireflection layer and a blue-pass filter serving as the heat sink. The constructed PiG converted LDs@sapphire exhibits a luminous efficacy of 217 lm W−1 and a CRI (color rendering index) of 57 at 3646 K under a driven power of 3 W. Compared to the conventional white LDs, the luminous efficacy and the resistance to laser irradiation of the white LDs@sapphire are obviously enhanced. Therefore, we predict that this white emitting PiG converted LDs@sapphire will become a promising candidate for future lighting sources and promote the use of sapphire plate as the heat sink.

At present, blue-red composite LED light sources used for plant lighting are mainly composed of blue light and red light; the blue light is provided by gallium nitride LED chips, but the full-width at half-maximum (FWHW) is only approximately 25 nm, while the blue light required by plants for photosynthesis is wider. Focusing on this problem, this work reported that a dual emitting phosphor-in-glass plate (Dual-PiGP) was prepared towards a high power and dual broadband emitter, in which BaMgAl10O17:Eu2+ (BAM) and CaAlSiN3:Eu2+ (CASN) provide blue and red emission, respectively. Dual-PiGP exhibited several merits, including a high quantum efficiency of 93.90%, a superior thermal stability (80.1%@150 °C of the peak intensity at 25 °C), and a dual broad spectrum with a full-width at half-maximum (FWHM) of 50 and 106 nm at 446 and 645 nm, respectively. Moreover, a proof-of-concept Dual-PiGP plant lamp for application in indoor plant factories was successfully fabricated with Dual-PiGP and a 385 nm emitting LED chip, yielding blue- (400–500 nm) and red-light (580–780 nm) emission that matches well with the absorption spectrum of chlorophyll. The Dual-PiGP plant lamps were applied indoors to cultivate Italian lettuce, and commercial plant lamps assembled by LED chips were chosen as reference. The cultivation results indicated that the biomass of Italian lettuce was 12.12% greater than those cultivated using commercial plant lamps. Further analysis also certificated that the content of soluble protein and total chlorophyll were also improved. The Dual-PiGP light converter strategy provides an option for next-generation plant growth LEDs.

To obtain white light-emitted diodes (wLEDs) with a low correlated color temperature (CCT) and a high color rendering index (CRI), red-emission is indispensable in their emission spectra. Herein, CaO:Ce3+,Li+,F− yellow phosphors with more red spectral component have been prepared via a high temperature solid-state reaction. As compared to the F− undoped samples, CaO:Ce3+,Li+,F− phosphor have lower critical doping concentration of Ce3+ and show stronger luminescence. At the critical concentration, a quantum efficiency of 66.4% and enhanced thermal and chemical stability were obtained in CaO:Ce3+,Li+,F−. Furthermore, a CaO:Ce3+,Li+,F−-based phosphor-in-glass (PiG) using the red-emitting glass system with the composition of SiO2–Na2CO3–Al2O3–CaO:Eu3+ as the host material was constructed and used for high-power white LED applications. Such PiG samples with different phosphor doping concentrations can satisfy various light color demands and display higher reliability than the CaO:Ce3+,Li+,F− phosphor. An optimal PiG-based wLED exhibits color coordinates of (0.3769, 0.3386), a CCT of 3774 K, a CRI of 82.5 and a LE of 73.1 when the mass ratio of phosphor to glass matrix was 7 : 50 in PiG. Moreover, such PiG-based wLED also showed acceptable color stability under different drive currents. All the above results demonstrate that CaO:Ce3+,Li+,F− can be expected to be a potential alternative yellow phosphor for blue light excited PiG based warm wLEDs, particularly for high-power devices.

Ultrastable red-emitting phosphor-in-glass (PiG) consisting of 3.5MgO·0.5MgF2·GeO2:Mn4+ (MMG:Mn4+) phosphor in a glass matrix was prepared for superior artificial plant growth LEDs (PGLs). These obtained PiG plates show a thermal conductivity of 1.671 W m−1 K−1 and an external quantum efficiency of 27.5%, which provides the strong foundation for the application in high-power artificial plant growth LEDs (PGLs). Furthermore, a proof-of-concept PGL using 36 pieces of the title PiG plate and 420 nm-blue LED chip was fabricated. The combination of ∼420 nm from chip and the ∼659 nm chip from the MMG:Mn4+ phosphor provide a well-matched spectrum with the absorption bands of photosynthetic pigments and the phytochrome (PR and PFR) of most green plants. As expected, the as-fabricated PGL-treated milk-Chinese cabbage cultured in the indoor plant factory showed that after 15 day-irradiation, the plant biomass was nearly 48.9% greater in treated sample than those cultured using the general R-B LED lamps. Further analysis also demonstrated that promotive effect can also be obtained in the level of ascorbic acid, soluble protein, soluble sugar and total chlorophyll. The PiG strategy presented in this paper afforded superior high-power artificial plant growth LEDs, which are crucial in the application of ecological agriculture.

Herein, Mn4+-activated Ca1−xYxAl12−xMgxO19 (x = 0–0.50) solid solutions were prepared using a conventional high-temperature solid-state reaction. Crystal structure transformation via chemical co-substitution of Y3+/Mg2+ for Ca2+/Al3+ was investigated in detail. The optical properties of Ca1−xYxAl12−xMgxO19 (x = 0–0.50) have been reported for the first time using a combination of techniques including structural refinement and luminescence measurements. Co-doping of Mg and Y cations within the CaAl12O19 host in a controlled manner resulted in the as-prepared samples with red/far-red ratio-tunable luminescence properties. The emission bands well-matched with the absorption band of phytochrome. Interestingly, enhanced Mn4+ luminescence can be obtained upon the addition of Mg2+ and Y3+. Unexpectedly, the quantum yields exhibit a slight change when x is in the range from 0.05 to 0.40; this indicates that these solid solutions have significant potential as lighting systems for plant growth.

Carbon dot (CD)-based solid-state fluorescent materials have attracted a lot of attention in recent years owing to their superior optical and environmentally friendly properties, demonstrating a potential use in many applications. However, previously reported CD-based solid-state fluorescent materials mostly assemble a type of CD in the matrix which has only a single characteristic peak, and those of assembled double CDs with two characteristic peaks are very rare. Such a drawback restricts their further application, particularly in the field of white light emitting diodes (WLEDs). Herein, a rare type of double CD-based fluorescent material has been synthesized with dual characteristic peaks at 420 nm and 635 nm via the one-step assembly of blue- and red-emissive carbon dots (bCDs, rCDs) into mesoporous aluminas (MAs). The MA non-fluorescent matrix neither competes for absorbing excitation light nor absorbs the emission from the CDs, leading to excellent PL emitting properties and color and thermal stabilities. The emissive colors are tunable in the white-light region simply through adjusting excitation wavelengths, showing their great potential for phosphor-based WLEDs. In the field of agricultural planting, transparent sunlight conversion films based on co-assembled phosphors have been obtained, revealing inherent optical properties and an efficient process for converting sunlight into blue and red lights, which are essential for plant photosynthesis.

Herein, NaYF4:Yb,Tm@SiO2/carbon dot nanocomposites have been successfully fabricated by a facile route. The structure and morphology of the nanocomposites were characterized by SEM, TEM, XRD, FT-IR and XPS measurements. It was demonstrated that carbon dots were embedded well in the silica layer coating on the surface of NaYF4:Yb,Tm nanoparticles, leading to a relatively stable structure of the nanocomposites. The nanocomposites showed interesting dual-mode luminescence properties, i.e. blue green light under a 365 nm UV lamp and blue purple light under a 980 nm laser. They were utilized to achieve light conversion films, ion detection probes and cell imaging, suggesting their great potential in the fields of anti-counterfeiting and bioapplications.

Phosphorescence is difficult to be observed from carbon dot powder due to the deliquescence and self-quenching in the aggregation state. In this study, aggregation-induced room temperature phosphorescence (RTP) is first reported in self-quenching-resistant nitrogen-doped carbon dot powder, which is suggested to take advantage of the moisture-resistance, rigidization and oxygen-barrier induced by PVA-chains. Furthermore, the optical mechanism of RTP as well as fluorescence is investigated through the abnormal excitation-responsive phenomena, and the potential application in temperature sensing is also preliminarily evaluated. This study may benefit in developing phosphorescence from undesirable aggregation through structure design and exploiting emerging applications for carbon dots.

Herein, unique S and N co-doped carbon dots (S,N-C-dots) were synthesized via a one-pot hydrothermal method. The S,N-C-dots not only possess a relatively high photoluminescence (PL) quantum yield (QY) (43%), but also present unique optical properties with dual-emission (blue and yellow) and excitation-independent characteristics. It is extremely rare for bare carbon dots (C-dots) to have dual-emission under single excitation wavelength. Herein, we achieved a series of solid-state lighting materials, such as silica-encapsulated C-dots (silica/C-dots), light conversion films (LCFs), and white-light-emitting diodes (WLEDs), using S,N-C-dots as a doping fluorophore. Moreover, we conducted some comparative experiments to prove that the unique properties of the S,N-C-dots were ascribed to the co-doping effects of S and N atoms. The yellow emission originates from the intrinsic state emission and the blue emission originates from the surface energy trap emission. This study presents a facile preparation of highly efficient dual-emissive S,N-C-dots and provides a new strategy to develop various solid-state lighting materials.

Probing intrinsic luminescence behaviors in known inorganic hosts is still of great importance to understand corresponding mechanisms and guide their possible applications. Nitride phosphor Ba2Si5N8:Eu2+, which shows interesting reddish-orange persistent luminescence but more famous for phosphor-conversion in white-LEDs, lacks adequate inquiries about two-peak emission, the full temperature range of thermal quenching and trap distribution. In this article, temperature-dependent photoluminescence, afterglow decay curves and photo-stimulated persistent luminescence of Ba2Si5N8:Eu2+ phosphors were investigated in detail. Evaluation of energy transfer at two emitting sites and luminescence quenching was based on careful investigation of photoluminescence at various temperatures. Furthermore, we proposed an integrated temperature-dependent afterglow decay curve method to estimate the trap density distribution in Ba2Si5N8:Eu2+ phosphor, accompanied by thermo-luminescence and photo-stimulated persistent luminescence analysis. Results indicate that integrating afterglow decay curves of various temperatures can be a useful attempt to detect trap distribution in charge carrier trapped materials.

Red-emitting CaAlSiN3:Eu2+ phosphors with different doping contents have been synthesized by solid-state reaction using calcium hydride as a calcium source. The emergence of persistent luminescence in CaAlSiN3:Eu2+ was originated from electron traps introduced by the partial substitutions of O in N sites to form positive trap levels at low Eu2+ concentration. The broad thermoluminescence emission bands indicated multiple trap levels, in which the shallow traps were mainly responsible for the red persistent luminescence; besides, the deep trap electrons could be efficiently released under extra NIR (980 nm) stimulation, resulting in enhanced photoluminescence and phosphorescence. It is expected that the enhanced emission under UV-NIR simultaneous excitation may be a promising technique to investigate the trap distributions in optical energy storage materials.

Correction for ‘Towards efficient dual-emissive carbon dots through sulfur and nitrogen co-doped’ by Wan Zhou et al., J. Mater. Chem. C, 2017, 5, 8014–8021.