The latest MaterChemFront issue is published online 
Following review type articles are included in current issue:
Design and effective synthesis methods for high-performance polymer semiconductors in organic field-effect transistors
Longxian Shi, Yunlong Guo, Wenping Hu and Yunqi Liu
Mater. Chem. Front., 2017,1, 2423-2456
http://dx.doi.org/10.1039/C7QM00169J
Designing hybrid architectures for advanced thermoelectric materials
Yun Zheng, Yubo Luo, Chengfeng Du, Beibei Zhu, Qinghua Liang, Huey Hoon Hng, Kedar Hippalgaonkar, Jianwei Xu and Qingyu Yan
Mater. Chem. Front., 2017,1, 2457-2473
http://dx.doi.org/10.1039/C7QM00306D
Recent advances in AIEgen-based luminescent metal–organic frameworks and covalent organic frameworks
Li Ma, Xiao Feng, Shan Wang and Bo Wang
Mater. Chem. Front., 2017,1, 2474-2486
http://dx.doi.org/10.1039/C7QM00254H
Late transition metal catalyzed α-olefin polymerization and copolymerization with polar monomers
Lihua Guo, Wenjing Liu and Changle Chen
Mater. Chem. Front., 2017,1, 2487-2494
http://dx.doi.org/10.1039/C7QM00321H
Understanding and suppressing side reactions in Li–air batteries
Ying Liu, Liping Wang, Lujie Cao, Chaoqun Shang, Zhenyu Wang, Hongen Wang, Liqing He, Jingyi Yang, Hua Cheng, Jingze Li and Zhouguang Lu
Mater. Chem. Front., 2017,1, 2495-2510
http://dx.doi.org/10.1039/C7QM00353F
The front cover story, 
Organic field effect transistors (OFETs), important components of organic electronics, have witnessed lots of breakthrough, partially due to their potential applications in radio frequency identification (RFID) tags, flexible displays, electronic papers, sensor and so forth. Thanks to the advantages of flexibility, light weight, transparency, solution-processability and modifiability, polymer semiconductors are one of the favorite choices for OFETs. In this Review Article, Yunlong Guo, Wenping Hu, and Yunqi Liu and coworkers from Institute of Chemistry, Chinese Academy of Sciences (China) and Tianjing University (China) summarized the progress of the third-generation donor-acceptor (D-A) polymers for OFETs with high performance, especially emphasizing on building block selection, backbone halogenation, side chain engineering and random copolymerization. They pointed out that once the chemical approaches mentioned above are combined with rational device architectures, more high-performance polymer based OFETs are expected.
The development of mechanochromic fluorescence (MCF) materials has attracted much attention due to their great potential in data storage, anti-counterfeiting, pressure sensors and display. However, the significantly variety in the origin of this stimuli-responsive systems makes it challenging to establish a general and specific design strategies to create new high-contrast MCF materials. In this Review Article, Zhen Li and co-worker from Wuhan University (China) summarized the mechanisms of different MCF cases from the viewpoint of molecular packing status, intermolecular interactions, and intramolecular conformation in polymorphism MCF systems. The critical roles of molecular packing and conformation in the force-to-luminescence process are discussed. The general thoughts of structure–packing–performance generated from the MCF materials might promote the further optimization of organic material performance in aggregated state.
The supply of power is one of the most important issues in modern life. Nowadays, lithium-ion batteries (LIBs) are still the leading power sources for electrical vehicles and still predominate in the battery market for portable electronic devices and green energy distribution. To break the limit of traditional LIBs with graphite as the anode material, many efforts have been attempted. In this Article, Yanwen Ma, Dan Wang and coworkers from Nanjing University of Posts & Telecommunications (China) and Institute of Process Engineering Chinese Academy of Sciences (China) utilized zeolitic imidazolate framework (ZIF) types of MOF strung by MnO2 NWs as precursors, to prepare C/Co-coated MnO nanowires (C/Co-MnO NWs), which could deliver 848.4 and 718 mA h g-1 at 500 and 5000 mA g-1 after 40 charge/discharge cycles, respectively, superior to other reported MOF-derived nanostructured materials.
Hydrogels, a special kind of three-dimensional cross-linked, water-swollen and hydrophilic polymers, have been extensively investigated for use in various applications as enviro-sensitive materials. Among various types of hydrogels, polyacrylate polymers such as polyacrylic acid (PAA) have the most versatile structure to enhance their practical utility in everyday life applications such as filtration, water remediation, diapers and hygiene products, cosmetics, wound dressings, medical waste solidification and metal ion removal. However, regardless of many advantages, the poor mechanical property of PAA hydrogels is considered as a marked weakness, and limited their specific applications. In this Article, Youhong Tang and coworkers from Flinders University (Australia) intelligently introduced a hyperbranched polymer into PAA, through in situ polymerization, to toughen PAA hydrogels with 130% improvement in the ultimate tensile strength, without sacrificing the swelling ratio.
Prompted by both scientific and commercial interests, organic materials with high performance are badly needed to be explored for organic light-emitting diodes (OLEDs). Specially, metal-free thermally activated delayed fluorescence (TADF) materials can achieve 100% use of excitons through reverse intersystem crossing (RISC) because of their low energy gap (DEST) between the lowest singlet excited state (S1) and the triplet excited state (T1). In this Article, Shijian Su, Yong Cao and coworkers from South China University of Technology (China) combined carbazole and two additional carbazole or diphenylamine moieties together with a benzophenone unit, to design two donor–acceptor (D–A) type TADF luminogens of CCDC and CCDD. A maximal EQE of 15.9%, the highest ever value among the reported benzophenone-based blue emitters, was achieved in the blue-emitting devices with CCDC as the emitter. And the green emitting CCDD-based devices demonstrated the maximal EQEs exceed 22% and the on-set voltages of as low as 2.6 V.
Solution-processed bulk heterojunction (BHJ) polymeric solar cells (PSCs) have attracted extensive attention in the past two decades due to their low cost, light weight, and potential for roll-to-roll production on flexible substrates. Instead of using fullerene acceptors, due to the efforts of scientists, especially the contributions from Xiaowei Zhan’s group (Peking University, China), some PSCs comprising conjugated polymers and non-fullerene acceptors have demonstrated high power-conversion efficiencies (PCE > 12%). So far, one of the major factors hindering industrial production of nonfullerene PSCs is the high sensitivity of the power conversion efficiency (PCE) to thickness variations, which can significantly affect the manufacturing yields and production costs of roll-to-roll processing. When the thickness of the active layer is over 100 nm, PCEs show a significant loss. In this Article, Long Ye, Shaoqing Zhang, Harald Ade and Jianhui Hou from University of Science and Technology Beijing (China), Institute of Chemistry, Chinese Academy of Sciences (China), and North Carolina State University (USA) reported that simply via thermal annealing, highly efficient thickness-insensitive non-fullerene PSCs could fabricated. For example, PBDB-T/IT-M-based nonfullerene PSCs can afford an impressive PCE of up to 9.4% at an active layer thickness of 250 nm, and a high efficiency close to 9%@400 nm, contributing much for the possible commercial roll-to-roll printing technology.
The front cover story,