A research group led by Prof. HAN Keli from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) revealed the new ultrafast UV energy dissipation mechanisms of plant sunscreen.
　　Schematic of the relaxation scheme of plant sunscreens in this work. (Image by ZHAO Xi and LUO Jian)
　　An overexposure to ultraviolet (UV) irradiation has deleterious effects on animals and plants. As a result, sinapoyl malate is deposited in the leaf epidermis of Arabidopsis plants and served as a sunscreen to prevent the penetration of deleterious ultraviolet irradiation. After absorption of UV light, sinapoyl malate undergoes a trans-cis nonradiative isomerization in dozens of picoseconds and results in the formation of cis product.
　　The scientists previously determined that the UV absorption ability of cis product was very important for the efficiency of this plant sunscreen. However, the excited-state relaxation path of the cis product remained unclear.
　　They used femtosecond transient absorption spectroscopy and various theoretical methods, including time-dependent functional theory, to explore the excited-state dynamics of cis-methyl sinapate (cis-MS), which was a simplified model of sinapates.
　　In addition to a non-adiabatic cis-trans isomerization path resulting in the formation of ground-state trans-MS, they found an adiabatic path where the excited-state cis-MS could form excited-state trans-MS directly.
　　This work provides a deep insight into the photoisomerization dynamics of plant sunscreen and was published in The Journal of Physical Chemistry Letters.
　　Furthermore, in order to construct a structure-function relationship of the sinapate sunscreens, the scientists made chemical modifications on the para-substitution of trans-MS and then explored their excited-state dynamics.
　　They found that after the para-hydroxyl group of MS was substituted by a hydrogen atom, a new dark excited state (denoted as V'(ππ*)) participated in the relaxation of initially populated bright V(ππ*) state. The nonradiative trans-cis photoisomerization evolved along the V(ππ*) state and was completed in about 20 picoseconds. In contrast, the V'(ππ*) state relaxed to the ground state mainly by emitting a photon and exhibited a lifetime as long as 5 nanoseconds, making it susceptible to the reactive chemicals in environment.
　　This is the first time to distinguish the V(ππ*) and V'(ππ*) states in experiment, giving a deep understanding of the photoisomerization mechanism of sinapates, as well as cinnamates. In addition, this work, also published in The Journal of Physical Chemistry Letters, suggests that the V'(ππ*) state should be avoided when designing a sinapate-based sunscreen.
　　The above work was supported by the National Key Research and Development Program of China. (Text by ZHAO Xi and LUO Jian)

　　Metal halide perovskites have sparked enormous research attentions due to their exceptional virtues involving high extinction coefficient, tunable band gap, long carrier diffusion length, low exciton binding energy. Such appealing properties render perovskites as a near-perfect photo-absorber and stimulate the development of perovskite solar cells.
　　Additive engineering has been developed to optimize perovskite quality. All inorganic devices are becoming increasingly prominent according to the requirement of long-term stability. Consequently, inorganic additives of metal cations are more attractive because most of them can enter the bulk phase or adsorb/exchange at the surface to tune the photoelectrical properties.
　　(a) Schematic of the ABX3 perovskite crystal structure and the elements that have been used in perovskites; (b) The ionic radius of various cations under different coordination numbers and the highest efficiency of the PVSCs with metal cation additives. (Image by WANG Kai and DUAN Lianjie)
　　Prof. LIU Shengzhong's group from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) achieved a series of innovations in perovskite solar cells. Recently, his group was invited to discuss the role of metal cations in perovskite solar cells.
　　The scientists discussed the metal cations for perovskite solar cells by focusing on the position of the cations in perovskites, the modulation of the film quality, and the influence on the photovoltaic performance. Metal cations were considered in the order of alkali cations, alkaline earth cations, then metal cations in the ds and d regions, and ultimately trivalent cations (p- and f-block metal cations) according to the periodic table of elements.
　　In addition, the effects of metal cations on the perovskite tolerability, film morphology, charge dynamics, crystal strain effect and stability were discussed systematically. Finally, the scientists highlighted the opportunities and challenges of metal cations in perovskite solar cells.
　　The above study was published as a review article in Advanced Materials.
　　The project was supported by the National Key Research and Development Program of China, National Natural Science Foundation of China, National University Research Fund and the 111 Project. (Text by WANG Kai and DUAN Lianjie)

　　A research group led by Prof. WU Zhong-Shuai from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences, developed the rechargeable aqueous planar Zn//MnO2 micro-batteries fabricated by low-cost, highly efficient, scalable screen printing technique.
　　Fabrication of printed Zn//MnO2 planar MBs. (Image by WANG Xiao and HOU Xiaocheng)
　　The rapid development of the new-generation miniaturized and wearable electronics has stimulated the demand for the corresponding miniature energy storage devices. The planar micro-batteries, which overcome the shortcomings of the traditional stacked geometry, such as large volume, poor mechanical flexibility, and easy separation of the interface under bending state, are a promising candidate for flexible electronics.
　　In order to address the safety issues, scientists are developing high-safety aqueous electrolytes to replace flammable organic electrolytes, and constructing high-safety aqueous planar micro-batteries.
　　Due to the abundance of their electrode materials, Zn//MnO2 micro-batteries have attracted many attentions. However, there is still a lack of simple, efficient and large-scale microfabrication technique for fabricating aqueous planar Zn//MnO2 micro-batteries.
　　In this work, thixotropic ink was firstly configured with manganese dioxide, zinc powder and graphene as active materials, to produce the positive, negative electrodes and the current collector of Zn//MnO2 batteries, respectively. Then, multi-step screen printing method was adopted to realize the simple and low-cost preparation of planar Zn//MnO2 micro-batteries.
　　The researchers found that the prepared Zn//MnO2 batteries showed not only environmental friendliness and high safety, but also exceptional durability, with a capacity of 83.9% for 1300 cycles at current density of 5 C, and good mechanical flexibility and performance uniformity.
　　In addition, the variety of printing substrates could meet the needs of different application scenarios. As screen printing is a mature technology in industry, this work would be highly promising for cost-efficient and large-scale preparation of planar Zn//MnO2 batteries, and offered new insights for the development of other planar flexible energy storage devices, and the research and application of graphene.
　　The above work was published in National Science Review. Meanwhile, it was highlighted by Prof. Sang-Young Lee's study entitled "Scalable and safer, printed Zn//MnO2 planar micro-batteries for smart electronics" in the same volume.
　　This work was supported by National Natural Science Foundation of China, National Key R&D Program of China, Dalian National Laboratory for Clean Energy (DNL), CAS, etc. (Text by WANG Xiao and HOU Xiaocheng)

　　Recently, a research group led by Prof. WANG Guoxiong and Prof. BAO Xinhe from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences was invited to review the development, challenges and prospects of high-temperature CO2 electrolysis in solid oxide electrolysis cells. This progress report was published in Advanced Materials (DOI: 10.1002/adma.201902033).
　　Solid oxide electrolysis cells (SOECs) are able to convert CO2 and H2O to syngas, hydrocarbon fuel at cathode, and pure oxygen at anode. SOECs have the advantages of possessing solid and modular structure, fast reaction kinetics, high energy efficiency and low cost. Therefore, they have promising applications in CO2 conversion and surplus renewable electricity storage.
　　Carbon‐neutral cycle based on CO2 electrolysis in SOECs. (Image by SONG Yuefeng)
　　The scientists summarized the development history of SOECs, reaction mechanism of CO2 electroreduction, electrolyte materials and electrode materials. And they introduced the effect of SOEC microstructure on the electrochemical performance, and highlighted the SOEC degradation，the advances of fuel-assisted SOEC and high-pressurized SOEC.
　　Finally they made a prospect for the future research such as utilizing density in situ physiochemical characterizations to monitor the elementary processes of the electrode reactions and incorporating the alkane conversion at anode of the SOEC to efficiently produce fuel and chemicals.
　　This research team has dedicated to high-temperature CO2 electrolysis in recent years, and has constructed a series of metal-oxide interfaces by infiltration and in situ exsolution. They increased the amount of surface oxygen vacancies, and promoted the CO2 activation at cathode and oxygen evolution reaction at anode, leading to the enhanced electrochemical performance.
　　The results of electrochemical impedance spectroscopy, in situ electrochemical X-ray photoelectron spectroscopy and density functional theory calculations revealed that the metal-oxide interface at cathode facilitates the dissociative adsorption of CO2, while the metal-oxide interface at anode triggers the oxygen spillover from oxide to metal surface.
　　This work was supported by the National Science Foundation of China, the National Key R&D Program of China, and the Strategic Priority Research Program of the Chinese Academy of Sciences. It was dedicated to the 70th anniversary of Dalian Institute of Chemical Physics, Chinese Academy of Sciences. (Text/Image by SONG Yuefeng)

　　A research team led by Prof. ZHANG Tao and Prof. LI Ning from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences synthesized JP-10 fuel with lignocellulosic platform compound, furfuryl alcohol. Their findings were published in Angew. Chem. Int. Ed..
　　A new strategy was first reported for the synthesis of bio-JP-10 fuel with furfuryl alcohol which has been produced in industrial scale with agricultural and forestry residues. (Image by LI Guangyi Li and LI Ning)
　　The synthesis of renewable jet fuel with lignocellulosic platform components has drawn a lot of attentions in recent years. So far, most of reported work was concentrated on the production of conventional jet fuels.
　　JP-10 is an advanced jet fuel which is obtained from fossil energy nowadays. However, the high price and low availability limit its application in civil aviation.
　　The scientists reported a new strategy for the synthesis of bio-JP-10 fuel with furfuryl alcohol, which has been produced in industrial scale with agricultural and forestry residues. Under the optimized conditions, high overall carbon yields (~65%) of bio-JP-10 fuel were achieved.
　　A preliminary economic analysis indicated that the price of bio-JP-10 fuel could be greatly decreased from ~7,091 US$/ton (by fossil route) to less than 5,600 US$/ton using this new strategy. The unit production costs for bio-JP-10 fuel could be decreased to less than 2,900 US$/ton when the price of furfuryl alcohol decreased to 400 US$/ton with the advancement of technology in the future.
　　Their findings bring practical application of bio-JP-10 fuel in sight.
　　This work was supported by the National Natural Science Foundation of China, the Strategic Priority Research Program of the Chinese Academy of Sciences, the National Key Projects for Fundamental Research and Development of China, DNL Cooperation Fund, CAS, Dalian Science Foundation for Distinguished Young Scholars. This is one of papers that dedicated to the 70th anniversary of Dalian Institute of Chemical Physics, Chinese Academy of Sciences. (Text by LI Guangyi Li and LI Ning).

　　A research group led by Prof. WU Zhong Shuai and Prof. BAO Xinhe from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences reviewed the recent development and progress of planar microbatteries (MBs) and micro-supercapacitors (MSCs), and highlighted the future road of MBs and MSCs from 2D to 3D device geometry. The study was published in Advanced Materials.
　　Schematic of the classified four types of MBs and MSCs (Image by ZHENG Shuanghao)
　　The rapid development and further modularization of miniaturized and self-powered electronic systems have substantially stimulated the urgent demand for microscale electrochemical energy storage devices, e.g., MBs and MSCs.
　　Recently, planar MBs and MSCs, composed of isolated thin-film microelectrodes with extremely minimized ionic diffusion path and even free of separator on a single substrate, are becoming particularly attractive. It is because they can be directly integrated with microelectronic devices on the same side of one single substrate to act as a stand-alone microsized power source or complement miniaturized energy harvesting units.
　　This report highlighted the development and recent advances of planar MBs and MSCs from the fundamentals and design principle to the fabrication methods of two-dimensional (2D) and three-dimensional (3D) planar microdevices in both in-plane and stacked geometries.
　　It provided a comprehensive analysis of the primary aspects of electrode materials, electrolyte, device architecture, and microfabrication techniques that eventually affect the performance metrics of microscale energy storage devices. The technical challenges and prospective solutions for high-energy-density planar MBs and MSCs with multi-functionalities were proposed.
　　This work was supported by National Natural Science Foundation of China, National Key R&D Program of China, etc. (Text by ZHENG Shuanghao and HOU Xiaocheng)