Search

Your search keyword '"P. Zhuang"' showing total 256 results
Start Over Author "P. Zhuang" Journal journal of the american chemical society
256 results on '"P. Zhuang"'

1. Dynamic Bubbling Balanced Proactive CO2 Capture and Reduction on a Triple-Phase Interface Nanoporous Electrocatalyst

Author

Zhang, Wei, Yu, Ao, Mao, Haiyan, Feng, Guangxia, Li, Cheng, Wang, Guanzhi, Chang, Jinfa, Halat, David, Li, Zhao, Yu, Weilai, Shi, Yaping, Liu, Shengwen, Fox, David W, Zhuang, Hao, Cai, Angela, Wu, Bing, Joshua, Fnu, Martinez, John R, Zhai, Lei, Gu, M Danny, Shan, Xiaonan, Reimer, Jeffrey A, Cui, Yi, and Yang, Yang

Subjects
Macromolecular and Materials Chemistry, Engineering, Chemical Sciences, Affordable and Clean Energy, General Chemistry, Chemical sciences
Abstract

The formation and preservation of the active phase of the catalysts at the triple-phase interface during CO2 capture and reduction is essential for improving the conversion efficiency of CO2 electroreduction toward value-added chemicals and fuels under operational conditions. Designing such ideal catalysts that can mitigate parasitic hydrogen generation and prevent active phase degradation during the CO2 reduction reaction (CO2RR), however, remains a significant challenge. Herein, we developed an interfacial engineering strategy to build a new SnOx catalyst by invoking multiscale approaches. This catalyst features a hierarchically nanoporous structure coated with an organic F-monolayer that modifies the triple-phase interface in aqueous electrolytes, substantially reducing competing hydrogen generation (less than 5%) and enhancing CO2RR selectivity (∼90%). This rationally designed triple-phase interface overcomes the issue of limited CO2 solubility in aqueous electrolytes via proactive CO2 capture and reduction. Concurrently, we utilized pulsed square-wave potentials to dynamically recover the active phase for the CO2RR to regulate the production of C1 products such as formate and carbon monoxide (CO). This protocol ensures profoundly enhanced CO2RR selectivity (∼90%) compared with constant potential (∼70%) applied at -0.8 V (V vs RHE). We further achieved a mechanistic understanding of the CO2 capture and reduction processes under pulsed square-wave potentials via in situ Raman spectroscopy, thereby observing the potential-dependent intensity of Raman vibrational modes of the active phase and CO2RR intermediates. This work will inspire material design strategies by leveraging triple-phase interface engineering for emerging electrochemical processes, as technology moves toward electrification and decarbonization.

Published
2024

3. Chemically Stable Polyarylether-Based Metallophthalocyanine Frameworks with High Carrier Mobilities for Capacitive Energy Storage

Author

Yang, Chongqing, Jiang, Kaiyue, Zheng, Qi, Li, Xinle, Mao, Haiyan, Zhong, Wenkai, Chen, Cheng, Sun, Bing, Zheng, Haimei, Zhuang, Xiaodong, Reimer, Jeffrey A, Liu, Yi, and Zhang, Jian

Subjects
Macromolecular and Materials Chemistry, Chemical Sciences, Physical Chemistry, Engineering, Materials Engineering, Affordable and Clean Energy, CSD-46-All CSGB, General Chemistry, Chemical sciences
Abstract

Covalent organic frameworks (COFs) with efficient charge transport and exceptional chemical stability are emerging as an import class of semiconducting materials for opto-/electronic devices and energy-related applications. However, the limited synthetic chemistry to access such materials and the lack of mechanistic understanding of carrier mobility greatly hinder their practical applications. Herein, we report the synthesis of three chemically stable polyarylether-based metallophthalocyanine COFs (PAE-PcM, M = Cu, Ni, and Co) and facile in situ growth of their thin films on various substrates (i.e., SiO2/Si, ITO, quartz) under solvothermal conditions. We show that PAE-PcM COFs thin films with van der Waals layered structures exhibit p-type semiconducting properties with the intrinsic mobility up to ∼19.4 cm2 V-1 s-1 and 4 orders of magnitude of increase in conductivity for PAE-PcCu film (0.2 S m-1) after iodine doping. Density functional theory calculations reveal that the carrier transport in the framework is anisotropic, with the out-of-plane hole transport along columnar stacked phthalocyanine more favorable. Furthermore, PAE-PcCo shows the redox behavior maximumly contributes ∼88.5% of its capacitance performance, giving rise to a high surface area normalized capacitance of ∼19 μF cm-2. Overall, this work not only offers fundamental understandings of electronic properties of polyarylether-based 2D COFs but also paves the way for their energy-related applications.

Published
2021

18. Direct Proximity Tagging of Small Molecule Protein Targets Using an Engineered NEDD8 Ligase

Author

Hill, Zachary B, Pollock, Samuel B, Zhuang, Min, and Wells, James A

Subjects
Medicinal and Biomolecular Chemistry, Chemical Sciences, Biotechnology, Generic health relevance, General Chemistry, Chemical sciences, Engineering
Abstract

Identifying the protein targets of bioactive small molecules remains a major problem in the discovery of new chemical probes and therapeutics. While activity-based probes and photo-cross-linkers have had success in identifying protein targets of small molecules, each technique has limitations. Here we describe a method for direct proximity tagging of proteins that bind small molecules. We engineered a promiscuous ligase based on the NEDD8 conjugating enzyme, Ubc12, which can be covalently linked to a small molecule of interest. When target proteins bind the small molecule, they are directly labeled on surface lysines with a biotinylated derivative of the small ubiquitin homologue, NEDD8. This unique covalent tag can then be used to identify the small molecule binding proteins. Utilizing the drug dasatinib, we have shown that dasatinib-directed NEDDylation occurs for known endogenous protein binders in complex cell lysates. In addition, we have been able to improve NEDDylation efficiency through rational mutagenesis. Finally, we have shown that affinity-directed NEDDylation can be applied to two other protein-ligand interactions beyond kinases. Proximity tagging using this engineered ligase requires direct binding of the target and, thus, provides a useful and orthogonal approach to facilitate small molecule target identification.

Published
2016

19. P-Block Aluminum Single-Atom Catalyst for Electrocatalytic CO2Reduction with High Intrinsic Activity

Author

Ma, Zhanshuai, Wang, Bingqing, Yang, Xiang, Ma, Chao, Wang, Weibo, Chen, Chengjin, Liang, Fangkui, Zhang, Nian, Zhang, Hui, Chu, Yongheng, Zhuang, Zhongbin, Xu, Haijun, Wang, Yu, and Liu, Junfeng

Abstract

Atomically dispersed transition metal sites on nitrogen-doped carbon catalysts hold great potential for the electrochemical CO2reduction reaction (CO2RR) to CO due to their encouraging selectivity. However, their intrinsic activity is restricted by the hurdle of the high energy barrier of either *COOH formation or *CO desorption due to the scaling relationship. Herein, we discover a p-block aluminum single-atom catalyst (Al–NC) featuring an Al–N4site that enables disentangling this hurdle, which endows a moderate reaction kinetic barrier for *COOH formation and *CO desorption, as validated by in situ attenuated total reflection infrared spectroscopy and theoretical simulations. As a result, the developed Al–NC shows a CO Faradaic efficiency (FECO) of up to 98.76% at −0.65 V vs RHE and an intrinsic catalytic turnover frequency of 3.60 s–1at −0.99 V vs RHE, exceeding those of the state-of-the-art Ni–NC and Fe–NC counterparts. Moreover, it also delivers a partial CO current of 309 mA·cm–2at 93.65% FECOand 605 mA at >85% FECOin a flow cell and membrane electrode assembly (MEA), respectively. Strikingly, when using low-concentration CO2(30%) as the feedstock, this catalyst can still deliver a partial CO current of 240 mA at >80% FECOin the MEA. Considering the earth-abundant character of the Al element and the high intrinsic activity of the Al–NC catalyst, it is a promising alternative to today’s transition metal-based single-atom catalysts.

Published
2024
Full Text
View/download PDF

20. Dynamic Bubbling Balanced Proactive CO2Capture and Reduction on a Triple-Phase Interface Nanoporous Electrocatalyst

Author

Zhang, Wei, Yu, Ao, Mao, Haiyan, Feng, Guangxia, Li, Cheng, Wang, Guanzhi, Chang, Jinfa, Halat, David, Li, Zhao, Yu, Weilai, Shi, Yaping, Liu, Shengwen, Fox, David W., Zhuang, Hao, Cai, Angela, Wu, Bing, Joshua, Fnu, Martinez, John R., Zhai, Lei, Gu, M. Danny, Shan, Xiaonan, Reimer, Jeffrey A., Cui, Yi, and Yang, Yang

Abstract

The formation and preservation of the active phase of the catalysts at the triple-phase interface during CO2capture and reduction is essential for improving the conversion efficiency of CO2electroreduction toward value-added chemicals and fuels under operational conditions. Designing such ideal catalysts that can mitigate parasitic hydrogen generation and prevent active phase degradation during the CO2reduction reaction (CO2RR), however, remains a significant challenge. Herein, we developed an interfacial engineering strategy to build a new SnOxcatalyst by invoking multiscale approaches. This catalyst features a hierarchically nanoporous structure coated with an organic F-monolayer that modifies the triple-phase interface in aqueous electrolytes, substantially reducing competing hydrogen generation (less than 5%) and enhancing CO2RR selectivity (∼90%). This rationally designed triple-phase interface overcomes the issue of limited CO2solubility in aqueous electrolytes via proactive CO2capture and reduction. Concurrently, we utilized pulsed square-wave potentials to dynamically recover the active phase for the CO2RR to regulate the production of C1 products such as formate and carbon monoxide (CO). This protocol ensures profoundly enhanced CO2RR selectivity (∼90%) compared with constant potential (∼70%) applied at −0.8 V (V vs RHE). We further achieved a mechanistic understanding of the CO2capture and reduction processes under pulsed square-wave potentials via in situ Raman spectroscopy, thereby observing the potential-dependent intensity of Raman vibrational modes of the active phase and CO2RR intermediates. This work will inspire material design strategies by leveraging triple-phase interface engineering for emerging electrochemical processes, as technology moves toward electrification and decarbonization.

Published
2024
Full Text
View/download PDF

21. Sulfur-Vacancy-Engineered Two-Dimensional Cu@SnS2–xNanosheets Constructed via Heterovalent Substitution for High-Efficiency Piezocatalytic Tumor Therapy

Author

Ma, Xinyu, Ding, Binbin, Yang, Zhuang, Liu, Sainan, Liu, Zhendong, Meng, Qi, Chen, Hao, Li, Jing, Li, Ziyao, Ma, Ping’an, and Lin, Jun

Abstract

Ultrasound (US)-mediated piezocatalytic tumor therapy has attracted much attention due to its notable tissue-penetration capabilities, noninvasiveness, and low oxygen dependency. Nevertheless, the efficiency of piezocatalytic therapy is limited due to an inadequate piezoelectric response, low separation of electron–hole (e––h+) pairs, and complex tumor microenvironment (TME). Herein, an ultrathin two-dimensional (2D) sulfur-vacancy-engineered (Sv-engineered) Cu@SnS2–xnanosheet (NS) with an enhanced piezoelectric effect was constructed via the heterovalent substitution strategy of Sn4+by Cu2+. The introduction of Cu2+ion not only causes changes in the crystal structure to increase polarization but also generates rich Svto decrease band gap from 2.16 to 1.62 eV and inhibit e––h+pairs recombination, collectively leading to the highly efficient generation of reactive oxygen species under US irradiation. Moreover, Cu@SnS2–xshows US-enhanced TME-responsive Fenton-like catalytic activity and glutathione depletion ability, further aggravating the oxidative stress. Both in vitro and in vivo results prove that the Sv-engineered Cu@SnS2–xNSs can significantly kill tumor cells and achieve high-efficiency piezocatalytic tumor therapy in a biocompatible manner. Overall, this study provides a new avenue for sonocatalytic therapy and broadens the application of 2D piezoelectric materials.

Published
2024
Full Text
View/download PDF

28. Photoswitching Mechanism of Cyanine Dyes

Author

Dempsey, Graham T, Bates, Mark, Kowtoniuk, Walter E, Liu, David R, Tsien, Roger Y, and Zhuang, Xiaowei

Subjects
Chemical Sciences, Physical Chemistry, Binding Sites, Carbocyanines, Electrons, Fluorescent Dyes, Hydrogen-Ion Concentration, Kinetics, Light, Mass Spectrometry, Photochemical Processes, Sulfhydryl Compounds, General Chemistry, Chemical sciences, Engineering
Abstract

Cyanine dyes have been shown to undergo reversible photoswitching, where the fluorophore can be switched between a fluorescent state and a dark state upon illumination at different wavelengths. The photochemical mechanism by which switching occurs has yet to be elucidated. In this study, we have determined the mechanism of photoswitching by characterizing the kinetics of dark state formation and the spectral and structural properties of the dark state. The rate of switching to the dark state depends on the concentration of the primary thiol in the solution and the solution pH in a manner quantitatively consistent with the formation of an encounter complex between the cyanine dye and ionized thiol prior to their conjugation. Mass spectrometry suggests that the photoconversion product is a thiol-cyanine adduct in which covalent attachment of the thiol to the polymethine bridge disrupts the original conjugated pi-electron system of the dye.

Published
2009

32. Temporally Decoupled Ammonia Splitting by a Zn–NH3Battery with an Ammonia Oxidation/Hydrogen Evolution Bifunctional Electrocatalyst as a Cathode

Author

Feng, Yangyang, Huang, Lanting, Xiao, Zhiwei, Zhuang, Xu, Aslam, Tayyab Sohail, Zhang, Xiang, Tan, Yan-Xi, and Wang, Yaobing

Abstract

Ammonia splitting to hydrogen is a decisive route for hydrogen economy but is seriously limited by the complex device and low efficiency. Here, we design and propose a new rechargeable Zn–NH3battery based on temporally decoupled ammonia splitting to achieve efficient NH3-to-H2conversion. In this system, ammonia is oxidized into nitrogen during cathodic charging (2NH3+ 6OH–→ N2+ 6H2O + 6e–) with external electrical energy conversion and storage, while during cathodic discharging, water is reduced to hydrogen (2H2O + 2e–→ H2+ 2OH–) with electrical energy generation. In this loop, continuous and efficient H2production without separation and purification is achieved. With the help of the ammonia oxidation reaction (AOR) and hydrogen evolution reaction (HER) bifunctional catalyst of Mo2C/NiCu@C, a rechargeable Zn–NH3battery is realized that exhibits a high NH3-to-H2FE of 91.6% with outstanding durability for 900 cycles (300 h) at 20 mA/cm2, enabling efficient and continuous NH3-to-H2conversion.

Published
2024
Full Text
View/download PDF

46. A Fluorinated BODIPY-Based Zirconium Metal–Organic Framework for In VivoEnhanced Photodynamic Therapy

Author

Chen, Xu, Mendes, Bárbara B., Zhuang, Yunhui, Conniot, João, Mercado Argandona, Sergio, Melle, Francesca, Sousa, Diana P., Perl, David, Chivu, Alexandru, Patra, Hirak K., Shepard, William, Conde, João, and Fairen-Jimenez, David

Abstract

Photodynamic therapy (PDT), an emergent noninvasive cancer treatment, is largely dependent on the presence of efficient photosensitizers (PSs) and a sufficient oxygen supply. However, the therapeutic efficacy of PSs is greatly compromised by poor solubility, aggregation tendency, and oxygen depletion within solid tumors during PDT in hypoxic microenvironments. Despite the potential of PS-based metal–organic frameworks (MOFs), addressing hypoxia remains challenging. Boron dipyrromethene (BODIPY) chromophores, with excellent photostability, have exhibited great potential in PDT and bioimaging. However, their practical application suffers from limited chemical stability under harsh MOF synthesis conditions. Herein, we report the synthesis of the first example of a Zr-based MOF, namely, 69-L2, exclusively constructed from the BODIPY-derived ligands via a single-crystal to single-crystal post-synthetic exchange, where a direct solvothermal method is not applicable. To increase the PDT performance in hypoxia, we modify 69-L2with fluorinated phosphate-functionalized methoxy poly(ethylene glycol). The resulting 69-L2@F is an oxygen carrier, enabling tumor oxygenation and simultaneously acting as a PS for reactive oxygen species (ROS) generation under LED irradiation. We demonstrate that 69-L2@F has an enhanced PDT effect in triple-negative breast cancer MDA-MB-231 cells under both normoxia and hypoxia. Following positive results, we evaluated the in vivoactivity of 69-L2@F with a hydrogel, enabling local therapy in a triple-negative breast cancer mice model and achieving exceptional antitumor efficacy in only 2 days. We envision BODIPY-based Zr-MOFs to provide a solution for hypoxia relief and maximize efficacy during in vivoPDT, offering new insights into the design of promising MOF-based PSs for hypoxic tumors.

Published
2024
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results