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Light‐driven hydrogen production from biomass derivatives offers a path towards carbon neutrality. It is often however operated with the limitations of sluggish kinetics and severe coking. Herein, a disruptive air‐promoted strategy is explored for efficient and durable light‐driven hydrogen production from ethanol over a core/shell Cr2O3@GaN nanoarchitecture. The correlative computational and experimental investigations show ethanol is energetically favorable to be adsorbed on the Cr2O3@GaN interface, followed by dehydrogenation toward acetaldehyde and protons by photoexcited holes. The released protons are then consumed for H2 evolution by photogenerated electrons. Afterward, O2 can be evolved into active oxygen species and promote the deprotonation and C−C cleavage of the key C2 intermediate, thus significantly lowering the reaction energy barrier of hydrogen evolution and removing the carbon residual with inhibited overoxidation. Consequently, hydrogen is produced at a high rate of 76.9 mole H2 per gram Cr2O3@GaN per hour by only feeding ethanol, air, and light, leading to the achievement of a turnover number of 266,943,000 mole H2 per mole Cr2O3 over a long‐term operation of 180 hours. Notably, an unprecedented light‐to‐hydrogen efficiency of 17.6 % is achieved under concentrated light illumination. The simultaneous generation of aldehyde from ethanol dehydrogenation enables the process more economically promising. [ABSTRACT FROM AUTHOR]

Herein, we report an unprecedented skeletal rearrangement reaction of tetrahydro‐β‐carbolines enabled by copper‐catalyzed single‐electron oxidative oxygenation, in which H2O and O2 act as oxygen sources to generate a unique 2‐hydroxyl‐3‐peroxide indoline intermediate. The synthetic reactivity of 2‐hydroxyl‐3‐peroxide indoline species was demonstrated by a unique multi‐step bond cleavage and formation cascade. Using a readily available copper catalyst under open‐air conditions, highly important yet synthetically difficult spiro[pyrrolidone‐(3,1‐benzoxazine)] products were obtained in a single operation. The synthetic utility of this methodology is demonstrated by the efficient synthesis of the natural products donaxanine and chimonamidine, as well as the 3‐hydroxyl‐pyrroloindoline scaffold, in just one or two steps. [ABSTRACT FROM AUTHOR]

Probing pro‐metastatic biomarkers is of significant importance to evaluate the risk of tumor metastasis, but spatially selective imaging of such targets in extracellular microenvironment is particularly challenging. By introducing the bilinguality of PNA/peptide hybrid that can speak both peptide substrate and nucleobase‐pairing languages to combine with aptamer technology, we designed a smart DNA nanodevice programmed to respond sequentially to dual pro‐metastatic targets, MMP2/9 and ATP, in extracellular tumor microenvironment (TME). The DNA nanodevice is established based on the combination of an ATP‐responsive aptamer sensor and a MMP2/9‐hydrolyzable PNA/peptide copolymer with a cell membrane‐anchoring aptamer module. Taking 4T1 xenograft as a highly aggressive tumor model, the robustness of the DNA nanodevice in spatioselective imaging of MMP2/9 and ATP in TME is demonstrated. We envision that this design will enable the simultaneous visualization of multiple pro‐metastatic biomarkers, which allows to gain insights into their pathological roles in tumor metastasis. [ABSTRACT FROM AUTHOR]