Chemically exfoliated two-dimensional MnO2 nanosheets are successfully modified with amino-polyethylene glycol as a theranostic platform for ultrasensitive stimuli-responsive theranostics of cancer. The highly dispersed MnO2 nanosheets exhibit a unique break-up in the mildly acidic microenvironment of tumor tissues, which could substantially enhance their in vitro and in vivo performances in T1 -weighted magnetic resonance imaging. Such a pH-triggered breaking-up behavior could further promote the fast release of loaded anticancer drugs for concurrent pH-responsive drug release and circumvent the multidrug resistance of cancer cells.

Rechargeable aluminum-ion batteries (AIBs) are attractive new generation energy storage devices due to its low cost, high specific capacity, and good safety. However, the lack of suitable electrode materials with high capacity and enhanced rate performance makes it difficult for real applications. Herein, the preparation of 3D reduced graphene oxide-supported SnS nanosheets hybrid is reported as a new type of cathode material for AIBs. The resultant material demonstrates one of the highest capacities of 392 mAh g at 100 mA g and good cycling stability. It is revealed that the layered SnS nanosheets anchored on 3D reduced graphene oxide network endows the composite not only high electronic conductivity but also fast kinetic diffusion pathway. As a result, the hybrid material exhibits high rate performance (112 mAh g at 1000 mA g ). The detailed characterization also verifies the intercalation and deintercalation of relatively large chloroaluminate anions into the layered SnS during the charge-discharge process, which is important for better understanding of the electrochemical process of AIBs.

Tuning hetero-interfaces between hybrid phases is a very promising strategy for designing advanced energy storage materials. Herein, we report a low-cost, high-yield and scalable two-step approach to prepare a new type of hybrid materials containing MoS 2 /graphene nanosheets prepared from ballmilling and exfoliation of commercial bulky MoS 2 and graphite. When tested as an anode material for sodium-ion battery, the as-prepared MoS 2 /graphene nanosheets exhibit remarkably high rate capability (284 mAh g -1 at 20 A g -1 (~30C) and 201 mAh g -1 at 50 A g -1 (~75C)) and excellent cycling stability (capacity retention of 95% after 250 cycles at 0.3 A g -1 ). Detailed experimental measurements and density functional theory calculation reveal that the functional groups in twodimensional (2D) MoS 2 /graphene heterostructures can be well tuned. The impressive rate capacity of as-prepared MoS 2 /graphene hybrids should be attributed to the heterostructures with low degree of defects and residual oxygen containing groups in graphene, which subsequently improve the electronic conductivity of graphene and decrease the Na + diffusion barrier during the MoS 2 /graphene interfaces in comparison with the acid treated one.

Rechargeable aluminum-ion batteries (AIBs) are considered as a new generation of large-scale energy-storage devices due to their attractive features of abundant aluminum source, high specific capacity, and high energy density. However, AIBs suffer from a lack of suitable cathode materials with desirable capacity and long-term stability, which severely restricts the practical application of AIBs. Herein, a binder-free and self-standing cobalt sulfide encapsulated in carbon nanotubes is reported as a novel cathode material for AIBs. The resultant new electrode material exhibits not only high discharge capacity (315 mA h g at 100 mA g ) and enhanced rate performance (154 mA h g at 1 A g ), but also extraordinary cycling stability (maintains 87 mA h g after 6000 cycles at 1 A g ). The free-standing feature of the electrode also effectively suppresses the side reactions and material disintegrations in AIBs. The new findings reported here highlight the possibility for designing high-performance cathode materials for scalable and flexible AIBs.

Over the last few decades, there has been increasing interest in the design and construction of integrated energy conversion and storage systems (IECSSs) that can simultaneously capture and store various forms of energies from nature. A large number of IECSSs have been developed with different combination of energy conversion technologies such as solar cells, mechanical generators and thermoelectric generators and energy storage devices such as rechargeable batteries and supercapacitors. This review summarizes the recent advancements to date of IECSSs based on different energy sources including solar, mechanical, thermal as well as multiple types of energies, with a special focus on the system configuration and working mechanism. With the rapid development of new energy conversion and storage technologies, innovative high performance IECSSs are of high expectation to be realised for diverse practical applications in the near future.