Photocatalytic hydrogen production using semiconductors is identified as one of the most promising routes for sustainable energy; however, it is challenging to harvest the full solar spectrum in a particulate photocatalyst for high activity. Herein, a hierarchical hollow black TiO2/MoS2/CdS tandem heterojunction photocatalyst, which allows broad‐spectrum absorption, thus delivering enhanced hydrogen evolution performance is designed and synthesized. The MoS2 nanosheets not only function as a cost‐effective cocatalyst but also act as a bridge to connect two light‐harvesting semiconductors into a tandem heterojunction where the CdS nanoparticles and black TiO2 spheres absorb UV and visible light on both sides efficiently, coupling with the MoS2 cocatalyst into a particulate photocatalyst system. Consequently, the photocatalytic hydrogen rate of the black TiO2/MoS2/CdS tandem heterojunction is as high as 179 µmol h−1 per 20 mg photocatalyst under visible‐light irradiation, which is almost 3 times higher than that of black TiO2/MoS2 heterojunctions (57.2 µmol h−1). Most importantly, the stability of CdS nanoparticles in the black TiO2/MoS2/CdS tandem heterojunction is greatly improved compared to MoS2/CdS because of the formation of tandem heterojunctions and the strong UV‐absorbing effect of black TiO2. Such a tandem architectural design provides new ways for synthesizing particulate photocatalysts with high efficiencies.

Interleukin-12 (IL-12) has emerged as one of the most potent agents for anti-tumor immunotherapy. However, potentially lethal toxicity associated with systemic administration of IL-12 precludes its clinical application. Here we redesign the molecule in such a way that its anti-tumor efficacy is not compromised, but toxic effects are eliminated. Deletion of the N-terminal signal peptide of IL-12 can effect such a change by preventing IL-12 secretion from cells. We use a newly designed tumor-targeted oncolytic adenovirus (Ad-TD) to deliver non-secreting (ns) IL-12 to tumor cells and examine the therapeutic and toxic effects in Syrian hamster models of pancreatic cancer (PaCa). Strikingly, intraperitoneal delivery of Ad-TD-nsIL-12 significantly enhanced survival of animals with orthotopic PaCa and cured peritoneally disseminated PaCa with no toxic side effects, in contrast to the treatment with Ad-TD expressing unmodified IL-12. These findings offer renewed hope for development of IL-12-based treatments for cancer.

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currents, geothermal, biomass, and solar, have been developed as alternatives. Among them, solar energy is the most abundant, inexpensive, nonpolluting, and sustainable. [5][6][7][8] Some semiconductors, so called photocatalysts, which possess the capacity to harvest solar energy to drive catalytic reactions for valuable chemical production, have been designed and fabricated to achieve efficient solar energy utilization. [9][10][11][12][13][14][15][16][17][18][19] Typically, TiO 2 is recognized as one of the most promising candidates due to its chemical stability, nontoxicity, and high resistance to photocorrosion. [20][21][22][23][24][25] In general, TiO 2 possesses three major phases, including anatase, rutile and brookite, and many other minor phases, such as monoclinic TiO 2 (B). All of them have wide bandgaps of 3.0-3.2 eV. Hence, TiO 2 can only absorb ultraviolet light (UV), while the visible light accounting for ≈43% of solar energy cannot be utilized. Furthermore, the rapid recombination of photogenerated electrons and holes severely limits its quantum efficiency. Thus, overall photocatalytic activity of TiO 2 is very limited, especially under visiblelight irradiation. [26][27][28] A complete photocatalytic reaction using TiO 2 -based photocatalysts involves three major steps: i) light absorption and The photocatalytic properties of TiO 2 have aroused a broad range of research interest since 1972 due to its abundance, chemical stability, and easily available nature. To increase its overall activity, in the past few decades, much effort has been devoted to the fabrication of advanced TiO 2 -based photocatalysts with visible-light response and these photocatalysts have shown great potential in the field of solar energy utilization. Here, recent progress in the investigation of visible-light responsive TiO 2 -based materials are reviewed. Notably, the fabrication strategies and corresponding chemical/ physical properties of visible-light responsive TiO 2 -based materials are described in detail, with a focus on bandgap engineering and junction engineering from the perspective of light absorption, charge transfer and separation, and surface reactions. Their applications in solar-fuel production, organic synthesis, bacterial disinfection, pollutant degradation and nitrogen fixation are also discussed. Moreover, the new trends and ongoing challenges in this field are proposed and highlighted.

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Ti3+ self-doped black TiO2 nanotubes (TDBTNs) with mesoporous nanosheet architecture have been successfully synthesized by solvothermal method combined with ethylenediamine encircling strategy to protect mesoporous frameworks, then calcined at 600 °C under hydrogen atmosphere. In this case, ethylenediamine molecules play important roles on maintaining the mesoporous networks and inhibiting the phase transformation from anatase-torutile effectively. The as-prepared TDBTNs with mesoporous nanosheet architecture possess a relatively high specific surface area of ∼95 m2 g–1 and an average pore size of ∼15.6 nm. The reduced bandgap of ∼2.87 eV extends the photoresponse from ultroviolet to visible light region due to the Ti3+ self-doping. The solar-driven photocatalytic hydrogen evolution rate for TDBTNs is approximately 3.95 mmol h–1 g–1, which is much better (about four times) than that of the pristine one (∼0.94 mmol h–1 g–1). This improvement is attributed to the reduced bandgap increasing the utilization ratio of solar energy, the formed Ti3+ enhancing separation efficiency of photogenerated charge carriers, and the special one-dimensional mesoporous architecture offering more surface active sites.

Under high-strain-rate compression (strain rate ∼103 s−1), nacre (mother-of-pearl) exhibits surprisingly high fracture strength vis-à-vis under quasi-static loading (strain rate 10−3 s−1). Nevertheless, the underlying mechanism responsible for such sharply different behaviors in these two loading modes remains completely unknown. Here we report a new deformation mechanism, adopted by nacre, the best-ever natural armor material, to protect itself against predatory penetrating impacts. It involves the emission of partial dislocations and the onset of deformation twinning that operate in a well-concerted manner to contribute to the increased high-strain-rate fracture strength of nacre. Our findings unveil that Mother Nature delicately uses an ingenious strain-rate-dependent stiffening mechanism with a purpose to fight against foreign attacks. These findings should serve as critical design guidelines for developing engineered body armor materials.

The design and synthesis of highly efficient thermally activated delayed fluorescence (TADF) emitters with an electroluminescence wavelength beyond 600 nm remains a great challenge for organic light-emitting diodes (OLEDs). To solve this issue, three TADF molecules, xDMAC−BP (x = 1, 2, 3), are developed in combination with the rigid planar dibenzo[a,c]phenazine (BP) acceptor core and different numbers of 9,9dimethylacridan (DMAC) donors. All these emitters possess stable internal charge transfer and a large dihedral angle between the donors and planar BP core. The emission wavelength can be regulated from 541 to 605 nm by increasing the number of the donor DMAC units because of the controllable tuning of the intramolecular charge transfer effect and the molecular geometrical structure. The photoluminescence quantum yields of these emitters are improved from 42 to 89% with the increase in the number of DMAC units. The orange-red OLEDs employing the xDMAC−BP emitters exhibit maximum external quantum efficiency (EQE) of 22.0% at 606 nm, which is the highest EQE of the previously reported TADF OLEDs exceeding 600 nm.