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1. Graphene oxide catalyzed ketone α-alkylation with alkenes: enhancement of graphene oxide activity by hydrogen bonding

   https://doi.org/10.1039/c9cc02578b  

   Meng, Guangrong; Patel, Mehulkumar; Luo, Feixiang; Li, Qingdong; Flach, Carol; Mendelsohn, Richard; Garfunkel, Eric; He, Huixin; Szostak, Michal (May 2019, Chemical Communications)

   Direct α-alkylation of carbonyl compounds represents a fundamental bond forming transformation in organic synthesis. We report the first ketone-alkylation using olefins and alcohols as simple alkylating agents catalyzed by graphene oxide. Extensive studies of the graphene surface suggest a pathway involving dual activation of both coupling partners. Notably, we show that polar functional groups have a stabilizing effect on the GO surface, which results in a net enhancement of the catalytic activity. The method represents the first alkylation of carbonyl compounds using graphenes, which opens the door for the development of an array of protocols for ketone functionalization employing common carbonyl building blocks and readily available graphenes. 

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2. Zinc oxide: reduced graphene oxide nanocomposite film for heterogeneous photocatalysis

   https://doi.org/10.1007/s11082-019-2132-1  

   Toporovska, L.; Turko, B.; Savchak, M.; Seyedi, M.; Luzinov, I.; Kostruba, A.; Kapustianyk, V.; Vaskiv, A. (January 2020, Optical and Quantum Electronics)
3. One-Pot Synthesis of Reduced Graphene Oxide/Metal (Oxide) Composites

   https://doi.org/10.1021/acsami.7b12539  

   Wu, Xu; Xing, Yuqian; Pierce, David; Zhao, Julia Xiaojun (October 2017, ACS Applied Materials & Interfaces)
4. Crystallization and melting of polymer chains on graphene and graphene oxide

   https://doi.org/10.1039/D3NR00817G  

   Ghasemi, Arman; Liao, Yangchao; Li, Zhaofan; Xia, Wenjie; Gao, Wei (July 2023, Nanoscale)

   This study employs all-atomistic (AA) molecular dynamics (MD) simulations to investigate the crystallization and melting behavior of polar and nonpolar polymer chains on monolayers of graphene and graphene oxide (GO). Polyvinyl alcohol (PVA) and polyethylene (PE) are used as representative polar and nonpolar polymers, respectively. A modified order parameter is introduced to quantify the degree of two-dimensional (2D) crystallization of polymer chains. Our results show that PVA and PE chains exhibit significantly different crystallization behavior. PVA chains tend to form a more rounded, denser, and folded-stemmed lamellar structure, while PE chains tend to form an elongated straight pattern. The presence of oxidation groups on the GO substrate reduces the crystallinity of both PVA and PE chains, which is derived from the analysis of modified order parameter. Meanwhile, the crystallization patterns of polymer chains are influenced by the percentage, chemical components, and distribution of the oxidation groups. In addition, our study reveals that 2D crystalized polymer chains exhibit different melting behavior depending on their polarity. PVA chains exhibit a more molecular weight-dependent melting temperature than PE chains, which have a lower melting temperature and are relatively insensitive to molecular weight. These findings highlight the critical role of substrate and chain polarity in the crystallization and melting of polymer chains. Overall, our study provides valuable insights into the design of graphene-based polymer heterostructures and composites with tailored properties. 

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5. 2D graphene oxide channel for water transport

   https://doi.org/10.1039/c8fd00026c  

   Mi, Baoxia; Zheng, Sunxiang; Tu, Qingsong (January 2018, Faraday Discussions)

   Layer-stacked graphene oxide (GO) membranes, in which unique two-dimensional (2D) water channels are formed between two neighboring GO nanosheets, have demonstrated great potential for aqueous phase separation. Subjects of crucial importance are to fundamentally understand the interlayer spacing ( i.e. channel height) of GO membranes in an aqueous environment, elucidate the mechanisms for water transport within such 2D channels, and precisely control the interlayer spacing to tune the membrane separation capability for targeted applications. In this investigation, we used an integrated quartz crystal mass balance (QCM-D) and ellipsometry to experimentally monitor the interlayer spacing of GO, reduced GO and crosslinked GO in aqueous solution and found that crosslinking can effectively prevent GO from swelling and precisely control the interlayer spacing. We then used molecular dynamics simulations to study the mass transport inside the 2D channels and proved that the chemical functional groups on the GO plane dramatically slow down water transport in the channels. Our findings on GO structure and water transport provide a necessary basis for further tailoring and optimizing the design and fabrication of GO membranes in various separation applications. 

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