Clinical applications of current photodynamic therapy (PDT) agents are often limited by their low singlet oxygen (1O2) quantum yields, as well as by photobleaching and poor biocompatibility. Here we present a new PDT agent based on graphene quantum dots (GQDs) that can produce 1O2 via a multistate sensitization process, resulting in a quantum yield of ~1.3, the highest reported for PDT agents. The GQDs also exhibit a broad absorption band spanning the UV region and the entire visible region and a strong deep-red emission. Through in vitro and in vivo studies, we demonstrate that GQDs can be used as PDT agents, simultaneously allowing imaging and providing a highly efficient cancer therapy. The present work may lead to a new generation of carbon-based nanomaterial PDT agents with overall performance superior to conventional agents in terms of 1O2 quantum yield, water dispersibility, photo- and pH-stability, and biocompatibility.

graphitic electrode. [ 8 ] Unfortunately, when applied in a dualgraphite battery, the EC molecules in the electrolyte can bind tightly with PF 6 − anions, and prevent the intercalation of these anions into the interlayer spaces of graphite positive electrodes. [ 9 ] Recently, with the developments of novel electrolyte formulas, several studies have reported signifi cantly improved reversibility of dual-carbon batteries. [ 10 ] Read et al. reported a reversible dual-graphite battery with simultaneous accommodation of Li + and PF 6 − in graphitic structures enabled by a high voltage electrolyte based on fl uorinated solvent and additive. [ 10a ] The battery demonstrated a reversible capacity of 60 mAh g −1 and a capacity retention of 62% after 50 cycles at C/7 rate. Rothermel et al. reported a dual-graphite battery based on a mixture of lithium bis-(trifl uoromethanesulfonyl)-imide (LiTFSI) and ionic liquid with SEI-forming additive. This electrolyte formula not only enabled stable TFSI − intercalation into the graphite positive electrode, but also allowed highly reversible intercalation of Li + into the graphite negative electrode. [ 10b ] Under an upper cut-off potential of 5.0 V, the full graphite battery presented a capacity of 97 mAh g −1 at a current rate of 10 mA g −1 , and 50 mAh g −1 at 500 mA g −1 , which shed light on the potential application of dual-ion batteries as an environmentally friendly energy storage technology.Herein, we report a novel aluminum-graphite dual-ion battery (AGDIB) in an ethyl-methyl carbonate (EMC) electrolyte with high reversibility and high energy density. It is the fi rst report on using an aluminum anode in dual-ion battery. The battery shows good reversibility, delivering a capacity of ≈100 mAh g −1 and capacity retention of 88% after 200 chargedischarge cycles at 2 C (1 C corresponding to 100 mA g −1 ). To the best of our knowledge, performance of the battery is among the best of reported dual-ion batteries.Figure 1 a schematically illustrates the initial and charged states of the AGDIB. Upon charging, PF 6 − anions in the electrolyte intercalate into the graphite cathode, while the Li + ions in the electrolyte deposit onto the aluminum counter electrode to form an Al-Li alloy. The discharge process is the reverse of the charge process, where both PF 6 − anions and Li + ions diffuse back into the electrolyte. The Al counter electrode acts as both the anode and the current collector, which greatly benefi ts the specifi c energy density and volumic energy density of the AGDIB. [ 11 ] Figure 1 b shows galvanostatic charge-discharge curves of the AGDIB, exhibiting a typical profi le of anion intercalation/deintercalation into/from graphite. The charge curve is mainly composed of three regions between 4.08 and 4.59 V (stage III), 4.59 and 4.63 V (stage II), and 4.63 and 5.0 V (stage I), each region corresponds to an anion intercalation stage of graphite, according to previous reports. [ 6e ] A dQ/dV differential curve of the battery is shown in the inset of Figure 1 b. Pe...

As an emerging clinical modality for cancer treatment, photodynamic therapy (PDT) takes advantage of the cytotoxic activity of reactive oxygen species (ROS) that are generated by light irradiating photosensitizers (PSs) in the presence of oxygen (O2). However, further advancements including tumor selectivity and ROS generation efficiency are still required. Substantial efforts are devoted to design and synthesize smart PSs with optimized properties for achieving a desirable therapeutic efficacy. This review summarizes the recent progress in developing intelligent PSs for efficient PDT, ranging from single molecules to delicate nanomaterials. The strategies to improve ROS generation through optimizing photoinduced electron transfer and energy transfer processes of PSs are highlighted. Moreover, the approaches that combine PDT with other therapeutics (e.g., chemotherapy, photothermal therapy, and radiotherapy) and the targeted delivery in cancer cells or tumor tissue are introduced. The main challenges for the clinical application of PSs are also discussed.