Precisely regulating the electronic structures of metal active species is highly desirable for electrocatalysis. Carbon-based substrates with inert surface provide weak metal-support interaction and thus are unable to modulate their electronic structures effectively.
　　Recently, a group led by Prof. LIU Jian from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences, in collaboration with Prof. ZHOU Si from Dalian University of Technology and Prof. LIANG Ji from Tianjin University, used single atoms to modify the carbon substrate to enhance the interaction between substrate and supported metal nanoparticles. The method could precisely tailor the electronic structures of metal nanoparticles.
　　This study was published in Angew. Chem. Int. Ed. on May 8.
　　 The cobalt single-atom doped carbon-supported Ru showed ultrahigh catalytic activity and stability (Image by SU Panpan)
　　The researchers dispersed single Co atoms on carbon substrate to enhance the interaction between substrate and the ruthenium (Ru) nanoreactor, which enabled remote regulation of the electronic states of Ru nanoparticles, and thereby tuning their electrocatalytic activity.
　　They took hydrogen evolution reaction (HER) as a model reaction, the cobalt single-atom doped carbon-supported Ru nanoreactor showed ultrahigh catalytic activity and stability.
　　Theoretical calculations showed that decoration of oxygen-containing graphene by single metal atoms induced electron redistribution on the carbon surface. The carbon atoms surrounding the single atoms were electron deficient, which enhanced the electron transfer from Ru nanoparticles to the carbon substrate, and thereby optimized the binding capability of Ru nanoreactor and its HER performance.
　　"This work realizes the efficient produce of green hydrogen using non-Pt electrocatalysts and provides a new strategy for steering the catalytic behavior of carbon-supported metal nanocatalysts in a more flexible and nondestructive manner," said by Prof. LIU. (Text by SU Panpan)

　　Integrating microscale electrochemical energy storage devices with microelectronics can convert intermittent renewable energy sources into a usable form through portable systems.
　　Inkjet printing process is a promising strategy for the customizable design of smart and flexible electronics. However, it's still a challenge to synthesize corresponding ink for inkjet printing.
　　Recently, Prof. WU Zhongshuai's group and Prof. LIU Shengzhong's group from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences developed an aqueous MXene/PH1000 (MP) hybrid ink for inkjet printing of micro-supercapacitors (MSCs).
　　This study was published in Advanced Energy Materials on April 28.
　　 
　　Schematic illustration of the fabrication of inkjet-printed MP-MSCs and the self-powered integrated system (Image by MA Jiaxin and ZHENG Shuanghao)
　　"We developed the ink for customizable fabrication of planar MSCs (MP-MSCs) with excellent shape diversity, record volumetric capacitance, integration, and modularization capabilities," said Prof. WU. 
　　The printable MP-MSCs delivered higher volumetric capacitance and energy density than those of most previously reported MSCs. This was attributed to the role of PH1000 in enhancing interlayer contact in the MXene to promote electron and ion transfer.
　　Moreover, MP-MSCs presented good miniaturization and modularization featuring, with high voltage output up to 36 V from 60 serially connected cells and impressive areal voltage of 5.4 V cm-2 connected in tandem.
　　This work was supported by National Natural Science Foundation of China, Dalian National Laboratory for Clean Energy of CAS. (Text by MA Jiaxin and ZHENG Shuanghao)

　　The provenance of oxygen on Earth and other solar planetary bodies is a fundamental issue. It is widely accepted that the prebiotic pathway of oxygen production in the Earth primitive atmosphere was via vacuum ultraviolet (VUV) photodissociation of CO2 and subsequent recombination of two O atoms.
　　In contrast, the photodissociation of H2O, one of the dominant oxygen carriers, has long been assumed to proceed mainly to produce hydroxyl (OH)- and hydrogen (H)-atom primary products, and its contribution to oxygen production is limited.
　　Recently, a research group led by Prof. YUAN Kaijun and YANG Xueming from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences revealed oxygen production from the three-body photodissociation of water molecule using the Dalian Coherent Light Source.
　　Their findings were published in Nature Communications on April 30. And the article was featured in a Nature Communications Editors’ Highlights webpage.
　　Dalian Coherent Light Source revealing three-body photodissociation of water as an important prebiotic-O2 source (Image by YUAN Kaijun)
　　The VUV free-electron laser facility at the Dalian Coherent Light Source allows the researchers to quantitatively assess the importance of H2O photochemistry for oxygen production.
　　"Our experimental results indicated that H2O under VUV excitation can break into three fragments: one O atom and two H atoms, where the O atoms are in the 1D and 3P states. The three-body dissociation process is the dominant channel for H2O photochemistry in the 90-110 nm region," said Prof. YUAN.
　　The quantitative determination demonstrated that approximately 20% of the H2O photoexcitation events resulted in O atoms. Considering the water abundance in widely interstellar circumstances such as in interstellar clouds, atmospheres of the solar-family comets, and even in the Earth primitive atmosphere, O production from water photolysis must be an important process. The subsequent recombination of O atoms produced O2, which represented an important prebiotic O2-production pathway.
　　This research was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences, Chemical Dynamics Research Center, and the National Natural Science Foundation of China. (Image by YUAN Kaijun)

　　Photocatalytic biomass conversion is an ideal way of generating syngas (H2 and CO) via C-C bond cleavage, which is initiated by hydrogen abstraction of O/C-H bond. However, the lack of efficient electron-proton transfer limits its efficiency. Conversional gasification of biomass into syngas needs to be operated at high temperature (400-700 °C).
　　Recently, a group led by Prof. WANG Feng from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. WANG Min from Dalian University of Technology, proposed a new method to realize photocatalytic conversion of biopolyols to syngas at room temperature with high efficiency.
　　This study was published in Journal of the American Chemical Society on April 27.
　　Schematic mechanism of the photoinduced PCET process over [SO4]/CdS (Image by ZHANG Xiaochen and LIU Huifang)
　　The researchers prepared surface sulfate ions modified CdS catalyst ([SO4]/CdS), which could simultaneously increase both the electron and proton transfer, thereby facilitating the generation of syngas mixture from biopolyols with high activity and selectivity.
　　In situ characterizations combined with theoretical calculations demonstrated that the surface sulfate ion [SO4] was bifunctional, serving as the proton acceptor to promote proton transfer, and increasing the oxidation potential of the valence band to enhance electron transfer.
　　Compared with pristine CdS, [SO4]/CdS exhibits 9-fold higher CO generation rate and 4-fold higher H2 generation. Through this method, a wide range of sugars, such as glucose, fructose, maltose, sucrose, xylose, lactose, insulin, and starch, were facilely converted into syngas.
　　This study reveals the pivotal effect of surface sulfate ion on electron–proton transfer in photocatalysis and provides a facile method for increasing photocatalytic efficiency. (Text by ZHANG Xiaochen and LIU Huifang)

　　Nicotinamide adenine dinucleotide (NAD), an indispensable cofactor in cells, participates in diverse redox biochemistry and other nonredox processes. NAD level variation leads to global yet difficult-to-predict biological responses.
　　A research team led by Prof. ZHAO Zongbao from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences has committed to developing non-natural cofactor-based systems to avoid the limitation associated with NAD level fluctuation.
　　The team has designed a non-natural coenzyme nicotinamide cytosine dinucleotide (NCD), and engineered a series of oxidoreductases. However, it's still challenging for microbial cells to take NCD from the environment.
　　Recently, the researchers created the synthetase for NCD and established NCD self-sufficient microbial phenotype for metabolic regulation.
　　This study was published on Nature Communication on April 9.
　　Created NcdS for NCD biosynthesis and the results of NCD-linked D-lactate accumulation (Image by WANG Xueying)
　　The researchers reprogrammed the ATP and nicotinic acid mononucleotide (NaMN) binding pockets of NaMN adenylyltransferase (NadD), the key enzyme in NAD biosynthesis, to favor CTP and nicotinamide mononucleotide (NMN).
　　"We created novel NCD synthetases (NcdSs) by combinatorial mutation of both key residues," said Prof. ZHAO.
　　Furthermore, they constructed NCD self-sufficient strains with different gradient NCD levels by precursor enhancement and pathway optimization. And the NCD level was up to 5.0 mM, higher than natural level of NAD.
　　They found that NCD synthesized in-situ could drive the selective conversion of L-malic acid to D-lactate in the presence of NCD-dependent malic enzyme mutant and D-lactate dehydrogenase mutant. NcdS together with NCD-linked enzymes may offer unique tools for intriguing studies in chemical biology and synthetic biology.
　　This work was supported by National Key R&D Program of China, National Natural Science Foundation of China. (Text by WANG Xueying)

　　Perovskite solar cells (PSCs), the third generation photovoltage technology, are obtaining more and more attention.
　　The power conversion efficiency of small area PSCs can reach over 25.5% by solution method. However, it is difficult to achieve uniform preparation in large area and high-throughput production by solution preparation technology, and the solvent residues also affect the stability of the devices.
　　Recently, a research team led by Prof. LIU Shengzhong from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences, in collaboration with Prof. FENG Jiangshan from Shaanxi Normal University, developed high-throughput large-area vacuum deposition for high-performance formamidine-based PSCs.
　　Their findings were published in Energy & Environmental Science on March 26.
　　(a) Schematic illustration of multisource vacuum deposition with an in-vacuum annealing process for large-area perovskite films. Photographs of FA-based perovskite films deposited on (b) glass and (c) PET substrates (Image by DUAN Lianjie and WANG Hui)
　　The researchers prepared CsxFA1-xPbI3 thin films with large size, high density and high quality on 400cm2 rigid and 300cm2 flexible substrates by layer-to-layer deposition technology. By combing with low vacuum and low temperature annealing strategy, they effectively regulated the nucleation and grain growth of perovskite thin films.
　　"The photoelectric conversion efficiency (PCE) of the PSC fabricated by combining the Spiro-OMeTAD hole transport layer (HTL) is 21.32%, which is the highest PCE of the PSC fabricated by vacuum method ever reported," said Prof. LIU.
　　In addition, the researchers resolved the HTLs prepared by vacuum method, and obtained PCE of 18.89% by full vacuum deposition method. The efficiency of a PSC prepared by the all-vacuum process increases by 1% from its initial value after storage in ambient in the dark for 189 days, demonstration the high stability of devices prepared by full vacuum method.
　　This study shows that the all-vacuum method can realize the large-area and high-throughput preparation of PSCs with high efficiency and high stability. (Text by DUAN Lianjie and WANG Hui)