The rapid development of emerging smart power source-integrated electronics with superthinness, flexibility, lightweight and unusual shape diversity has ultimately accelerated the pursuit of new-concept energy storage systems. However, the conventional energy storage systems, such as batteries and supercapacitors, are manufactured by stacking and packaging cell components (two electrodes, separator, current collectors), followed by injection of liquid electrolytes. As a result, these traditional systems have huge limitations of the fixed shapes, large size, bulk volume and heavy weight. Further, these power sources suffer from the leakage of liquid electrolytes, use of polymer binder, additive, thick separator, two pieces of flexible substrates. Hence, such traditional power sources can't keep pace with the progress of shape-tailored, flexible, smart integrated circuits.
　　The Dalian Institute of Chemical Physics (DICP) scientists WU Zhongshuai and BAO Xinhe et al developed a versatile printable technology to fabricate arbitrary-shaped, all graphene-based planar sandwich supercapacitors with outstanding performance, excellent flexibility, superior integration, and applicable scalability. This work has been published online in ACS Nano.
　　The arbitrary-shaped printable graphene-based planar sandwich supercapacitors (denoted as PG-PSSs) were successfully fabricated on one single substrate. The PG-PSSs were based on a monolithic layer-structured film of electrochemically exfoliated graphene as two electrodes and nanosized graphene oxide as a separator. The PG-PSSs possess designable geometries and multiple functionalities far beyond those attainable by conventional supercapacitor technologies. First of all, the printable technique allows us for the simplified mass production of planar sandwich supercapacitors with arbitrary shape. For instance, the supercapacitors with rectangle, hollow-square, "A" letter, "1" and "2" numbers, circle, and even complicated junction-wire shape were fabricated. Secondly, the diversity of graphene materials provided a platform for constructing monolithic PG-PSSs. Third, the versatile-shaped PG-PSSs exhibited superior flexibility, very stable performance without capacitance degradation under different bending states. Importantly, the output capacitance of our devices can be easily modulated by covering gel electrolyte on the selected area of the electrode film. In addition, such PG-PSSs can be readily interconnected in parallel and series for designable integrated circuits with high output current and voltage.
　　Figure. Arbitrary shaped supercapacitors (Image by ZHENG Shuanghao and ZHAO Xuejun)
　　More importantly, this strategy for PG-PSSs is highly reliable and scalable, and compatible for various on-demand high-throughput printing techniques, in particular, high-resolution inkjet printing, 3D printing, and roll-to-roll process. Through further improvement of using advanced materials and electrolytes, our approach can be extended to other 2D materials for massive production of complex-shaped, fully printed PSSs. These PG-PSSs with designable functionalities are universally applicable to versatile-shaped flexible and wearable electronic devices.
　　The research work was financially supported by Ministry of Science and Technology of China, National Natural Science Foundation of China, Natural Science Foundation of Liaoning Province and DICP. (Text and Image by ZHENG Shuanghao and ZHAO Xuejun)
　　Dr. LU Xinyi
　　Dalian Institute of Chemical Physics, Chinese Academy of Sciences,
　　457 Zhongshan Road, Dalian, 116023, China,
　　Tel: 86-411-84379201
　　E-mail: luxinyi@dicp.ac.cn 

　　The rapid development of emerging smart power source-integrated electronics with superthinness, flexibility, lightweight and unusual shape diversity has ultimately accelerated the pursuit of new-concept energy storage systems. However, the conventional energy storage systems, such as batteries and supercapacitors, are manufactured by stacking and packaging cell components (two electrodes, separator, current collectors), followed by injection of liquid electrolytes. As a result, these traditional systems have huge limitations of the fixed shapes, large size, bulk volume and heavy weight. Further, these power sources suffer from the leakage of liquid electrolytes, use of polymer binder, additive, thick separator, two pieces of flexible substrates. Hence, such traditional power sources can't keep pace with the progress of shape-tailored, flexible, smart integrated circuits.
　　The Dalian Institute of Chemical Physics (DICP) scientists WU Zhongshuai and BAO Xinhe et al developed a versatile printable technology to fabricate arbitrary-shaped, all graphene-based planar sandwich supercapacitors with outstanding performance, excellent flexibility, superior integration, and applicable scalability. This work has been published online in ACS Nano.
　　The arbitrary-shaped printable graphene-based planar sandwich supercapacitors (denoted as PG-PSSs) were successfully fabricated on one single substrate. The PG-PSSs were based on a monolithic layer-structured film of electrochemically exfoliated graphene as two electrodes and nanosized graphene oxide as a separator. The PG-PSSs possess designable geometries and multiple functionalities far beyond those attainable by conventional supercapacitor technologies. First of all, the printable technique allows us for the simplified mass production of planar sandwich supercapacitors with arbitrary shape. For instance, the supercapacitors with rectangle, hollow-square, "A" letter, "1" and "2" numbers, circle, and even complicated junction-wire shape were fabricated. Secondly, the diversity of graphene materials provided a platform for constructing monolithic PG-PSSs. Third, the versatile-shaped PG-PSSs exhibited superior flexibility, very stable performance without capacitance degradation under different bending states. Importantly, the output capacitance of our devices can be easily modulated by covering gel electrolyte on the selected area of the electrode film. In addition, such PG-PSSs can be readily interconnected in parallel and series for designable integrated circuits with high output current and voltage.
　　Figure. Arbitrary shaped supercapacitors (Image by ZHENG Shuanghao and ZHAO Xuejun)
　　More importantly, this strategy for PG-PSSs is highly reliable and scalable, and compatible for various on-demand high-throughput printing techniques, in particular, high-resolution inkjet printing, 3D printing, and roll-to-roll process. Through further improvement of using advanced materials and electrolytes, our approach can be extended to other 2D materials for massive production of complex-shaped, fully printed PSSs. These PG-PSSs with designable functionalities are universally applicable to versatile-shaped flexible and wearable electronic devices.
　　The research work was financially supported by Ministry of Science and Technology of China, National Natural Science Foundation of China, Natural Science Foundation of Liaoning Province and DICP. (Text and Image by ZHENG Shuanghao and ZHAO Xuejun)
　　Dr. LU Xinyi
　　Dalian Institute of Chemical Physics, Chinese Academy of Sciences,
　　457 Zhongshan Road, Dalian, 116023, China,
　　Tel: 86-411-84379201
　　E-mail: luxinyi@dicp.ac.cn 

　　Energy metabolism is essential to all living organisms. To mediate energy transfer, nature uses ATP and pyridine nucleotide coenzymes such as reduced nicotinamide adenosine dinucleotide (NADH) as energy carrier (EC). Because natural EC link multiple energy transfer modules and biological processes, it is intrinsically challenging to control energy transfer at the EC level.
　　To establish selective control over cellular energy transfer, Prof. ZHAO Zongbao and his co-workers at Dalian Institute of Chemical Physics, CAS, proposed to implement non-natural cofactor as EC. In an early study, ZHAO’s group chemically synthesized nicotinamide cytosine dinucleotide (NCD), and engineered some redox enzymes to use NCD (J. Am. Chem. Soc., 2011, 133, 20857). It was found that those engineered enzymes could function similarly to their natural counterparts in terms of catalytic efficiency and substrate/product selectivity.
　　In the current study, efforts have led to generating phosphite dehydrogenase mutant (Pdh*) to favor NCD and realized efficient production of NCDH at the expense of phosphite (ACS Catalysis, DOI: 10.1021/acscatal.6b03579). By using in vitro multi-enzyme systems, more experiments showed that NCDH-linked subsystem functioned independent of natural cofactor-linked redox system.
　　ZHAO’s group then devised Escherichia coli strain that overexpressed Pdh*, NCD-linked malic enzyme (Mae*) and nucleotide transporter (Ndt). It was found that, cells took up NCD and used phosphite as the electron source to generate NCDH that drove reductive carboxylation of pyruvate for improved malate production from glucose. Thus, it provides an opportunity to establish an orthogonal energy-transfer system for engineering cell factories and may be used to set an additional layer of a control mechanism for life.
　　Figure. E. coli WL005 harboring the circuit Pdh-Mae-NCD and expressing the transporter Ndt (Image by LIU Wujun)
　　The research work was financially supported by Minister of Science and Technology of China, National Natural Foundation of China and State Key Laboratory of Catalysis.（Text and Image by LIU Wujun）
　　

　　Energy metabolism is essential to all living organisms. To mediate energy transfer, nature uses ATP and pyridine nucleotide coenzymes such as reduced nicotinamide adenosine dinucleotide (NADH) as energy carrier (EC). Because natural EC link multiple energy transfer modules and biological processes, it is intrinsically challenging to control energy transfer at the EC level.
　　To establish selective control over cellular energy transfer, Prof. ZHAO Zongbao and his co-workers at Dalian Institute of Chemical Physics, CAS, proposed to implement non-natural cofactor as EC. In an early study, ZHAO’s group chemically synthesized nicotinamide cytosine dinucleotide (NCD), and engineered some redox enzymes to use NCD (J. Am. Chem. Soc., 2011, 133, 20857). It was found that those engineered enzymes could function similarly to their natural counterparts in terms of catalytic efficiency and substrate/product selectivity.
　　In the current study, efforts have led to generating phosphite dehydrogenase mutant (Pdh*) to favor NCD and realized efficient production of NCDH at the expense of phosphite (ACS Catalysis, DOI: 10.1021/acscatal.6b03579). By using in vitro multi-enzyme systems, more experiments showed that NCDH-linked subsystem functioned independent of natural cofactor-linked redox system.
　　ZHAO’s group then devised Escherichia coli strain that overexpressed Pdh*, NCD-linked malic enzyme (Mae*) and nucleotide transporter (Ndt). It was found that, cells took up NCD and used phosphite as the electron source to generate NCDH that drove reductive carboxylation of pyruvate for improved malate production from glucose. Thus, it provides an opportunity to establish an orthogonal energy-transfer system for engineering cell factories and may be used to set an additional layer of a control mechanism for life.
　　Figure. E. coli WL005 harboring the circuit Pdh-Mae-NCD and expressing the transporter Ndt (Image by LIU Wujun)
　　The research work was financially supported by Minister of Science and Technology of China, National Natural Foundation of China and State Key Laboratory of Catalysis.（Text and Image by LIU Wujun）
　　

　　Two-dimensional (2D) layered perovskites (A)2(CH3NH3)n-1MnX3n+1 have recently emerged as an attractive material for applications in photovoltaics and other optoelectronic devices (A is a large aliphatic or aromatic alkylammonium cation working as an insulating layer, M is the metal cation, and X is the halide anion). It has demonstrated that 2D layered perovskite films actually comprised multiple perovskite phases (with various n values from 1, 2, 3 and 4 to near ∞), even though the films were intended to be prepared as a single-phase. This hybrid feature seems to be ineluctable in fabricating 2D films.
　　However, it's still a burning question that how the different perovskite phases align in the hybrid films. Moreover, it is also unclear whether the band alignment between different phases can induce energy funneling or instead charges separation.
　　The latter is especially important because it dictates the application of these hybrid 2D perovskite films. Energy funneling is useful for light emitting applications, whereas charge separation would be more beneficial for light conversion or detection.
　　The Hybrid 2D Perpvslite Film (Image by LENG Jing and JIN Shengye)
　　The research group led by Prof. JIN Shengye in Dalian Institute of Chemical Physics studied the charge carrier dynamics in 2D multi-layered perovskite films, using ultrafast transient absorption and photoluminescence spectroscopy. Researchers found that multiple perovskite phases inside 2D layered perovskite film (including n = 2, 3, 4 and ≈ ∞) naturally align in the order of n along the direction perpendicular to the substrate. Driven by the band alignment between 2D perovskites phases, researchers observed consecutive photoinduced electron transfer from small-n to large-n phases. And the hole transfers in the opposite direction on hundreds of picoseconds inside the 2D film with the thickness around 358 nm. This internal charge transfer efficiently separates electrons and holes to the upper and bottom surfaces of the films. The phenomenon is a unique property beneficial for applications in photovoltaics and other optoelectronics devices.
　　The related results were published in Journal of the American Chemical Society (DOI: 10.1021/jacs.6b12581). This work is financially supported by Ministry of Science and Technology (2016YFA0200602) and National Nature Science Foundation of China (2013CB834604). (Text and Image by LENG Jing and JIN Shengye)
　　Dr. LU Xinyi
　　Dalian Institute of Chemical Physics, Chinese Academy of Sciences,
　　457 Zhongshan Road, Dalian, 116023, China,
　　Tel: 86-411-84379201
　　E-mail: luxinyi@dicp.ac.cn 

　　Two-dimensional (2D) layered perovskites (A)2(CH3NH3)n-1MnX3n+1 have recently emerged as an attractive material for applications in photovoltaics and other optoelectronic devices (A is a large aliphatic or aromatic alkylammonium cation working as an insulating layer, M is the metal cation, and X is the halide anion). It has demonstrated that 2D layered perovskite films actually comprised multiple perovskite phases (with various n values from 1, 2, 3 and 4 to near ∞), even though the films were intended to be prepared as a single-phase. This hybrid feature seems to be ineluctable in fabricating 2D films.
　　However, it's still a burning question that how the different perovskite phases align in the hybrid films. Moreover, it is also unclear whether the band alignment between different phases can induce energy funneling or instead charges separation.
　　The latter is especially important because it dictates the application of these hybrid 2D perovskite films. Energy funneling is useful for light emitting applications, whereas charge separation would be more beneficial for light conversion or detection.
　　The Hybrid 2D Perpvslite Film (Image by LENG Jing and JIN Shengye)
　　The research group led by Prof. JIN Shengye in Dalian Institute of Chemical Physics studied the charge carrier dynamics in 2D multi-layered perovskite films, using ultrafast transient absorption and photoluminescence spectroscopy. Researchers found that multiple perovskite phases inside 2D layered perovskite film (including n = 2, 3, 4 and ≈ ∞) naturally align in the order of n along the direction perpendicular to the substrate. Driven by the band alignment between 2D perovskites phases, researchers observed consecutive photoinduced electron transfer from small-n to large-n phases. And the hole transfers in the opposite direction on hundreds of picoseconds inside the 2D film with the thickness around 358 nm. This internal charge transfer efficiently separates electrons and holes to the upper and bottom surfaces of the films. The phenomenon is a unique property beneficial for applications in photovoltaics and other optoelectronics devices.
　　The related results were published in Journal of the American Chemical Society (DOI: 10.1021/jacs.6b12581). This work is financially supported by Ministry of Science and Technology (2016YFA0200602) and National Nature Science Foundation of China (2013CB834604). (Text and Image by LENG Jing and JIN Shengye)
　　Dr. LU Xinyi
　　Dalian Institute of Chemical Physics, Chinese Academy of Sciences,
　　457 Zhongshan Road, Dalian, 116023, China,
　　Tel: 86-411-84379201
　　E-mail: luxinyi@dicp.ac.cn