Hypoxia in a tumor microenvironment (TME) has inhibited the photodynamic therapy (PDT) efficacy. Here, Ni 3 S 2 /Cu 1.8 S nanoheterostructures were synthesized as a new photosensitizer, which also realizes the intracellular photocatalytic O 2 evolution to relieve hypoxia in TME and enhance PDT as well. With the narrow band gap (below 1.5 eV), the near infrared (NIR) (808 nm) can stimulate their separation of the electron−hole. The novel Z-scheme nanoheterostructures, testified by experimental data and density functional theory (DFT) calculation, possess a higher redox ability, endowing the photoexited holes with sufficient potential to oxide H 2 O into O 2 , directly. Meanwhile, the photostimulated electrons can capture the dissolved O 2 to form a toxic reactive oxygen species (ROS). Moreover, Ni 3 S 2 /Cu 1.8 S nanocomposites also possess the catalase-/peroxidase-like activity to convert the endogenous H 2 O 2 into • OH and O 2 , which not only cause chemodynamic therapy (CDT) but also alleviate hypoxia to assist the PDT as well. In addition, owing to the narrow band gap, they possess a high NIR harvest and great photothermal conversion efficiency (49.5%). It is noted that the nanocomposites also exhibit novel biodegradation and can be metabolized and eliminated via feces and urine within 2 weeks. The present single electrons in Ni/Cu ions induce the magnetic resonance imaging (MRI) ability for Ni 3 S 2 /Cu 1.8 S. To make sure that the cancer cells were specifically targeted, hyaluronic acid (HA) was grafted outside and Ni 3 S 2 /Cu 1.8 S@HA integrated photodynamic therapy (PDT), chemodynamic therapy (CDT), and photothermal therapy (PTT) to exhibit the great anticancer efficiency for hypoxic tumor elimination.

A comprehensive and concrete exploration into the deactivation mechanisms of luminescent materials is imperative, with the improvement of simulating and computing technology. In this study, an integrated calculation scheme is employed on five Ir(III) complexes for thorough investigation of their photophysical properties, including radiative ( k) and nonradiative ( k) decay rates. As a most famous Ir(III) complex with superior quantum efficiency, fac-Ir(ppy) herein serves as a reference relative to the other four β-diketonate complexes. Both temperature-independent and temperature-dependent k are taken into account quantitatively for the first time, to unearth the role of different ancillary ligands in the determination of luminescent properties. Since the validated calculations of k for the five complexes are of the same order of magnitude, the nonemissive peculiarity of 4 is caused by large k. The newly designed compound 5, which simply has two more -CH groups than 4 in the ancillary ligand, further manifests that the reason for large k in molecule 4 should be attributed to the ligand resonance caused by great π conjugation.

Currently, the limited intratumoral H2O2 level restricts the development of chemodynamic therapy (CDT). Herein, MoSe2/CoSe2@PEG nanosheets are prepared to reveal NIR‐photocatalytic H2O2 generation to insure the intracellular H2O2 supplement. The formation mechanism is investigated, showing the dissolved O2 and photo‐excited electrons to determine H2O2 production via sequential single‐electron transfer process. The experimental data and density functional theory calculation further display their typical‐II heterostructure, which possesses the effective charge separation and nearly four times H2O2 generation than MoSe2@PEG. In addition, the nanocomposites also reveal the peroxidase/catalase activity, making the in‐situ H2O2 activation and ·OH generation. And, the O2 production derived from catalase‐mimic activity not only relieves hypoxia but also offers the source for H2O2 production. Because of the decreased resistance for charge transfer, MoSe2/CoSe2@PEGs also reveal more than three times enzyme‐activity for MoSe2@PEG. With the narrow band gap and high NIR‐harvest, MoSe2/CoSe2@PEG exhibits the great photothermal converting ability (62.5%). MoSe2/CoSe2@PEG reveals the novel biodegradation, and most of them can be eliminated via urine and feces within 2 weeks. Here, the computed tomography/magnetic resonance imaging/photothermal imaging and the synergistic photothermal therapy/CDT treatments further make sure potential application on anticancer.

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We report, from a theoretical point of view, the first comparative study between the highly water-stable hydroxamate and the widely used carboxylate, in addition to the robust phosphate anchors. Theoretical calculations reveal that hydroxamate would be better for photoabsorption. A quantum dynamics description of the interfacial electron transfer (IET), including the underlying nuclear motion effect, is presented. We find that both hydroxamate and carboxylate would have efficient IET character; for phosphate the injection time is significantly longer (several hundred femtoseconds). We also verified that the symmetry of the geometry of the anchoring group plays important roles in the electronic charge delocalization. We conclude that hydroxamate can be a promising anchoring group, as compared to carboxylate and phosphate, due to its better photoabsorption and comparable IET time scale as well as the experimental advantage of water stability. We expect the implications of these findings to be relevant for the design of more efficient anchoring groups for dye-sensitized solar cell (DSSC) application.

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Theoretical investigation reveals how graphene enhances the photoelectric conversion efficiency of a DSSC.