Nanozymes as artificial enzymes that mimicked natural enzyme-like activities have received great attention in cancer diagnosis and therapy. Biomimetic nanozymes require more consideration regarding complicated tumor microenvironments to mimic biological enzymes, thus achieving superior nanozyme activity in vivo. Here we report a biomimetic hybrid nanozyme (named rMGB) which integrates natural enzyme glucose oxidase (GOx) with nanozyme manganese dioxide (MnO 2 ) by mutual promotion for maximizing the enzymatic activity of MnO 2 and GOx. Under hypoxia environment, we observed that MnO 2 could react with endogenous H 2 O 2 to produce O 2 for enhancing the catalytic efficiency of GOx for starvation therapy. Meanwhile, we confirmed that glucose oxidation generated gluconic acid and further improved the catalytic efficiency of MnO 2 subsequently. The biochemical reaction cycle, consisting of MnO 2 , O 2 , GOx, and H + , was triggered by the tumor microenvironment and accelerated each other so as to achieve self-supplied H + and accelerate O 2 generation, enhancing the starvation therapy, alleviating tumor hypoxia and accelerating the reactive oxygen species generation in photodynamic therapy. This biomimetic hybrid nanozyme would further facilitate the development of biological nanozymes for cancer treatment.

In current times, CO2 capture and lightweight energy storage are receiving significant attention and will be vital functions in next-generation materials. Porous carbonaceous materials have great potential in these areas, whereas most of the developed carbon materials still have significant limitations, such as nonrenewable resources, complex and costly processing, or the absence of tailorable structure. In this study, a new strategy is developed for using the currently underutilized lignin and cellulose nanofibers, which can be extracted from renewable resources to produce high-performance multifunctional carbon aerogels with a tailorable, anisotropic pore structure. Both the macro- and microstructure of the carbon aerogels can be simultaneously controlled by carefully tuning the weight ratio of lignin to cellulose nanofibers in the precursors, which considerably influences their final porosity and surface area. The designed carbon aerogels demonstrate excellent performance in both CO2 capture and capacitive energy storage, and the best results exhibit a CO2 adsorption capacity of 5.23 mmol g–1 at 273 K and 100 kPa and a specific electrical double-layer capacitance of 124 F g–1 at a current density of 0.2 A g–1, indicating that they have great future potential in the relevant applications.

A straightforward synthesis of indole-2-carboxylic esters was developed through a ligand-free copper-catalysed condensation/coupling/deformylation cascade process from 2-halo aryl aldehydes or ketones with ethyl isocyanoacetate. The reactions proceeded well for most of the 2-iodo-, bromo-, and chloro-substrates under room temperature or mild conditions.

Energy storage devices such as supercapacitors of high performance are in great need due to the continuous expansion of digitalization and related devices for mobile electronics, autonomous sensors, and vehicles of different kinds. However, the nonrenewable resources and often complex preparation processes associated with electrode materials and structures pose limited scale-up in production and difficulties in versatile utilization of the devices. Here, free-standing and flexible carbon nanofiber networks derived from renewable and abundant bioresources are demonstrated. By a simple optimization of carbonization, the carbon nanofiber networks reach a large surface area of 1670 m 2 g −1 and excellent specific gravimetric capacitance of ∼240 F g −1 , outperforming many other nanostructured carbon, activated carbon, and even those decorated with metal oxides. The remarkable electrochemical performance and flexibility of the green carbon networks enable an all-solid-state supercapacitor device, which displays a device capacitance of 60.4 F g −1 with a corresponding gravimetric energy density of 8.4 Wh kg −1 while maintaining good mechanical properties.

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