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Abstract In classical photodynamic therapy, tumor cells are killed by the cytotoxic species via type‐I/II photochemical reactions, seriously limited by the external photoexcitation and hypoxia. Herein, the electron transfer mechanism between fluorophores and peroxalate‐H2O2 reaction is investigated and the singlet/triplet electron exchange is utilized to achieve long‐persistent chemiluminescence imaging and synergistic type‐I/II/III photodynamic therapy. As a proof‐of‐concept, the photosensitizers of carbon nanodots (CDs)‐loaded chlorin e6 (CDs‐Ce6) are designed and integrated with the peroxalate molecules, and the as‐prepare polymer carbon nanodots (p‐CDs) exhibit novel tumor microenvironment (TME)‐responsive long‐persistent near‐infrared CL and photochemical reactions, evoking the in vivo imaging and synergistic dynamic therapy in tumor tissue. Mechanistically, the excess reactive oxygen species in TME can trigger the chemically initiated singlet/triplet electron exchange between the hydrophobic CDs‐Ce6 and peroxalate‐derived 1,2‐dioxetanes and thus the excess excited singlet/triplet electron of the CDs‐Ce6 can ensure the long‐persistent near‐infrared CL, type I/II photochemical production of hydroxyl radicals, superoxide radical and singlet oxygen, and type III photochemical damage of maladjusted biomacromolecules, enabling the long‐persistent near‐infrared biological imaging and enhanced cancer therapy. These results shed a new sight into the energy transfer mechanism in chemiluminescence and pave a new sight into the architecture of multifunctional theragnostic nanoplatforms.

Abstract It remains a challenge to obtain biocompatible afterglow materials with long emission wavelengths, durable lifetimes, and good water solubility. Herein we develop a photooxidation strategy to construct near-infrared afterglow carbon nanodots with an extra-long lifetime of up to 5.9 h, comparable to that of the well-known rare-earth or organic long-persistent luminescent materials. Intriguingly, size-dependent afterglow lifetime evolution from 3.4 to 5.9 h has been observed from the carbon nanodots systems in aqueous solution. With structural/ultrafast dynamics analysis and density functional theory simulations, we reveal that the persistent luminescence in carbon nanodots is activated by a photooxidation-induced dioxetane intermediate, which can slowly release and convert energy into luminous emission via the steric hindrance effect of nanoparticles. With the persistent near-infrared luminescence, tissue penetration depth of 20 mm can be achieved. Thanks to the high signal-to-background ratio, biological safety and cancer-specific targeting ability of carbon nanodots, ultralong-afterglow guided surgery has been successfully performed on mice model to remove tumor tissues accurately, demonstrating potential clinical applications. These results may facilitate the development of long-lasting luminescent materials for precision tumor resection.

Abstract Physical unclonable functions (PUFs) have emerged as a promising encryption technology, utilizing intrinsic physical identifiers that offer enhanced security and tamper resistance. Multi‐level PUFs boost system complexity, thereby improving system reliability and fault tolerance. However, crosstalk‐free multi‐level PUFs remain a persistent challenge. In this study, a hierarchical PUF system that harnesses the spontaneous phase separation of silk fibroin /PVA blend and the random distribution of silicon‐vacancy diamonds within the blend is presented. The thermodynamic instability of phase separation and inherent unpredictability of diamond dispersion gives rise to intricate random patterns at two distinct scales, enabling time‐efficient hierarchical authentication for cryptographic keys. These patterns are complementary yet independent, inherently resistant to replication and damage thus affording robust security and reliability to the proposed system. Furthermore, customized authentication algorithms are constructed: visual PUFs authentication utilizes neural network combined structural similarity index measure, while spectral PUFs authentication employs Hamming distance and cross‐correlation bit operation. This hierarchical PUF system attains a high recognition rate without interscale crosstalk. Additionally, the coding capacity is exponentially enhanced using M‐ary encoding to reinforce multi‐level encryption. Hierarchical PUFs hold significant potential for immediate application, offering unprecedented data protection and cryptographic key authentication capabilities.

Abstract Advanced sustainable biomedical materials are urgently needed for clinical applications; however, developing biomedical materials with exceptional mechanical and bactericidal properties as well as removable functionalities to reduce unintended secondary injury remains a challenge. Here, we report a biomass‐derived composite consisting of water‐soluble fish gelatin (FG) and antibacterial ZnO@silk fibroin (ZSF) microspheres for potential application as the wound dressing. The ZSF microspheres are embedded in a FG matrix to realize the stretchable, antibacterial, and removable ZSF/FG composites. By introducing glycerin as the plasticizer, ZSF/FG composites deliver a tensile strength of 4.5 MPa and stretchability of 550%. Acting as both the germicide and hydrophile components, ZSF microspheres endow the composites with excellent antibacterial capacity and water solubility. To prevent secondary injury, the ZSF/FG composites can be easily removed from the wounds by simply exposing them to excess water. Additionally, the ZSF/FG composites exhibit favorable biocompatibility and sustain high cell viability of over 100%. The full‐thickness skin wound model on infected mice demonstrated an efficient rate of wound closure and a reduced inflammatory response. The ZSF/FG composite shows promise to hasten the healing of infected wounds and is expected a promising candidate as wound dressing for clinical therapy.

Abstract Advanced antibacterial technologies are needed to counter the rapid emergence of drug-resistant bacteria. Image-guided therapy is one of the most promising strategies for efficiently and accurately curing bacterial infections. Herein, a chemiluminescence (CL)-dynamic/guided antibacteria (CDGA) with multiple reactive oxygen species (ROS) generation capacity and chemiexcited near-infrared emission has been designed for the precise theranostics of bacterial infection by employing near-infrared emissive carbon nanodots (CDs) and peroxalate as CL fuels. Mechanistically, hydrogen peroxide generated in the bacterial microenvironment can trigger the chemically initiated electron exchange between CDs and energy-riched intermediate originated from the oxidized peroxalate, enabling bacterial induced inflammation imaging. Meanwhile, type I/II photochemical ROS production and type III ultrafast charge transfer from CDs under the self-illumination can inhibit the bacteria proliferation efficiently. The potential clinical utility of CDGA is further demonstrated in bacteria infected mice trauma model. The self-illuminating CDGA exhibits an excellent in vivo imaging quality in early detecting wound infections and internal inflammation caused by bacteria, and further are proven as efficient broad-spectrum antibacterial nanomedicines without drug-resistance, whose sterilizing rate is up to 99.99%.

Wafer-scale phase-controlled 2D MoTe2 layers was synthesized for in-situ fabrication of room-temperature high-performance broadband infrared photodetector and device array.

Ultraviolet high-energy photons of phosphorescent carbon dots for antibacterial applications. Herein, the UV phosphorescent CNDs were achieved by decreasing conjugation size and spatial confinement. As a demonstration, the CNDs are used to inactivate gram-negative/positive bacteria.

Abstract Viral infection can lead to serious illness and death around the world, as exemplified by the spread of COVID-19. Using irradiation rays can inactive virions through ionizing and non-ionizing effect. The application of light in viral inactivation and the underlying mechanisms are reviewed by the research group of Dayong Jin from University of Technology Sydney.

Abstract Carbon nanodots (CDs) have emerged as an alternative option for traditional nanocrystals due to their excellent optical properties and low toxicity. Nevertheless, high emission efficiency is a long‐lasting pursuit for CDs. Herein, CDs with near‐unity emission efficiency are prepared via atomic condensation of doped pyrrolic nitrogen, which can highly localize the excited states thus lead to the formation of bound excitons and the symmetry break of the π–electron conjugation. The short radiative lifetimes (

Nanodiamonds (NDs) have excellent mechanical and optical properties, large surface area, easy bioconjugation and high biocompatibility, which makes them especially appealing for various potential applications. In recent years, NDs have received considerable attention in nanomedicine, and some noteworthy progress has been achieved. This review summarizes the synthetic routes and unique properties of NDs. In addition, the recent progress of NDs in nanomedical applications, including bioimaging, drug delivery and biosensing, is also discussed. We further provide an outlook towards the future developments and applications of NDs.

Abstract Biomass as sustainable and renewable resource has been one of the important energy sources for human life. Herein, luminescent nano-biomass dots (NBDs) have been extracted from soybean through ultrasonic method, which endows biomass with fluorescence property. The as-prepared NBDs are amorphous in structure with an average diameter of 2.4 nm and show bright blue fluorescence with a quantum yield of 16.7%. Benefiting from the edible raw materials and heating-free synthesis process, the cytotoxicity test shows that the cell viability still keeps 100% even if the concentration of the NBDs reaches 800 μg/ml, indicating the good biocompatibility of the NBDs. In addition, the fluorescence of the NBDs is very sensitive to Fe3+, which can be used for Fe3+ detection in terms of their health superiority. The limit of detection (LOD) of the proposed sensor was determined as 2.9 μM, which is lower than the maximum allowable level of Fe3+ (5.37 μM) in drinking water.

The authors would like to update the XPS spectrum in Figure 3c [...]

Abstract Optical multiplexing attracts considerable attention in the field of information encryption, optical probe, and time‐resolved bioimaging. However, the optical multiplexing based on rare‐earth nanoparticles suffers from heavy metal elements and relatively short lifetimes; sophisticated facilities are thus needed. Herein, time division duplexing based on eco‐friendly carbon nanodots (CNDs) with manipulative luminescence lifetimes is demonstrated. In a single green color emission channel, the luminescence lifetimes of the CNDs can be manipulated from nanosecond level to second level by introducing water, while the lifetime of the CNDs confined by a silica shell stays. Time division duplexing based on the CNDs and CNDs@silica with distinct lifetimes is realized and spatio‐temporal overlapping information is thus resolved. High‐level information encryption using the time division duplexing technology is realized. This work may promise the potential applications of CNDs in multi‐lifetime channels biological imaging, high‐density information storage, and anti‐counterfeiting.

Abstract Reactive oxygen species (ROS) are generated in the body and related to many pathophysiological processes. Hence, detection of ROS is indispensable in understanding, diagnosis, and treatment of many diseases. Here, near‐infrared (NIR) chemiluminescent (CL) carbon nanodots (CDs) are fabricated for the first time and their CL quantum yield can reach 9.98 × 10−3 einstein mol−1, which is the highest value ever reported for CDs until now. Nanointegration of NIR CDs and peroxalate (P‐CDs) through the bridging effect of amphiphilic triblock copolymer can serve as turn‐on probes for the detection and imaging of hydrogen peroxide (H2O2). Considering high efficiency and large penetration depth of NIR photons, the P‐CDs are employed in bioimaging H2O2 in vitro and in vivo, and the detection limit can reach 5 × 10−9 m, among the best reported of CDs‐based sensors. Moreover, imaging of inflammatory H2O2 in a mouse model of peritonitis is achieved by employing the P‐CDs as sensors. The results may provide a clue for the diagnosis and treatment of inflammation or cancers employing CL CDs as sensors.

Abstract Hydrogen peroxide (H2O2) is an important product of oxidase-based enzymatic reactions, such as glucose/glucose oxidase (GOD) reaction. Therefore, the probing of generated H2O2 for achieving the detection of various carbohydrates and their oxidases is very significative. Herein, we report one kind of dual-emission carbon nanodots (CDs) that can serve as novel dual-mode nanosensors with both fluorometric and colorimetric output for the selective detection of H2O2. The dual-model nanosensors are established only by the undecorated dual-emission CDs, where significant fluorometric and colorimetric changes are observed with the addition of different concentrations of H2O2 in the CD solution, which benefit to the achievement of the naked-eye detection for H2O2. The mechanism of the nanosensors can be attributed to the fact that the external chemical stimuli like hydroxyl radicals from H2O2 bring about the change of surface properties and the aggregation of CDs, which dominate the emission and absorption of CDs. The constructed dual-mode nanosensors exhibit good biocompatibility and high selectivity toward H2O2 with a linear detection range spanning from 0.05 to 0.5 M and allow the detection of H2O2 as low as 14 mM.

Abstract Red/near‐infrared (NIR) emissive carbon nanodots (CNDs) with photoluminescence (PL) quantum yield (QY) of 57% are prepared via an in situ solvent‐free carbonization strategy for the first time. 1‐Photon and 2‐photon cellular imaging is demonstrated by using the CNDs as red/NIR fluorescence agent due to the high PL QY and low biotoxicity. Further study shows that the red/NIR CNDs exhibit multiphoton excited (MPE) upconversion fluorescence under excitation of 800–2000 nm, which involves three NIR windows (NIR‐I, 650–950 nm; NIR‐II, 1100–1350; NIR‐III, 1600–1870 nm). 2‐Photon, 3‐photon, and 4‐photon excited fluorescence of the CNDs under excitation of different wavelengths is achieved. This study develops an in situ solvent‐free carbonization method for efficient red/NIR emissive CNDs with MPE upconversion fluorescence, which may push forward the application of the CNDs in bioimaging.

Abstract The various luminescent properties of carbon nanodots (CDs) reveal fascinating applications in several areas. Here, bright and multicolor chemiluminescence (CL) is realized from CDs, whose CL quantum yield can be optimized by adjusting the energy level alignment between the CDs and 1,2‐dioxetanedione intermediate generated from the reaction of peroxalate and hydrogen peroxide. A CL quantum yield of 9.32 × 10−3 Einsteins mol−1, maximal luminance of 3.28 cd m−2, and lifetime of 186.4 s are achieved in red CDs, all of which are the best values ever reported for CDs. As a proof‐of‐concept prototype, a high‐quality information encryption strategy is established via CD based CL imaging techniques by virtue of the high brightness and multicolor CL.

We investigate the possibilities to realize light extraction from single crystal diamond (SCD) nanopillars. This was achieved by dedicated 519 nm laser-induced spin-state initiation of negatively charged nitrogen vacancies (NV−). We focus on the naturally-generated by chemical vapor deposition (CVD) growth of NV−. Applied diamond was neither implanted with 14N+, nor was the CVD synthesized SCD annealed. To investigate the possibility of light extraction by the utilization of NV−’s bright photoluminescence at room temperature and ambient conditions with the waveguiding effect, we have performed a top-down nanofabrication of SCD by electron beam lithography (EBL) and dry inductively-coupled plasma/reactive ion etching (ICP-RIE) to generate light focusing nanopillars. In addition, we have fluorinated the diamond’s surface by dedicated 0 V SF6 ICP plasma. Light extraction and spin manipulations were performed with photoluminescence (PL) spectroscopy and optically detected magnetic resonance (ODMR) at room temperature. We have observed a remarkable effect based on the selective 0 V SF6 plasma etching and surprisingly, in contrast to literature findings, deactivation of NV− centers. We discuss the possible deactivation mechanism in detail.

Single crystal diamonds with strong NV− luminescence were prepared by high-pressure high-temperature method and followed by electron irradiation and annealing process. The stimulated emission and gain characteristics of NV− diamond in femtosecond time scale are also studied using the transient absorption technique. Stimulated emission was observed at 660–800 nm, with an optical gain displayed in the range of 680–725 nm. Further test revealed that the optical gain lifetime is 3.5 ns and the gain coefficient is 0.16 cm−1, demonstrating the potential realization of color center lasers.

To increase the responsivity is one of the vital issues for a photodetector. By employing ZnO as a representative material of ultraviolet photodetectors and Si as a representative material of visible photodetectors, an impact ionization process, in which additional carriers can be generated in an insulating layer at a relatively large electric field, has been employed to increase the responsivity of a semiconductor photodetector. It is found that the responsivity of the photodetectors can be enhanced by tens of times via this impact ionization process. The results reported in this paper provide a general route to enhance the responsivity of a photodetector, thus may represent a step towards high-performance photodetectors.