28 Sep. 2022, Our work “Fast Charge Transfer between Iodide Ions and Delocalized Electron System on the Graphite Surface for Boosting Hydrogen Energy Production” has been accepted by J. Mater. Chem. A

Fast Charge Transfer between Iodide Ions and Delocalized Electron System on the Graphite Surface for Boosting Hydrogen Energy Production. just accepted by J. Mater. Chem. A

Shih-Mao Peng,1 Shivaraj B. Patil,1 Chun-Chih Chang,2 Shu-Ting Chang,1 Yi-Chia Chen,1 Kuan-Chang Wu,1 Wei-Nien Su,3,4* Bing Joe Hwang,4,5,6* Di-Yan Wang1*

Developing new catalysts to reduce the energy barrier for hydrogen production from water splitting has been an important research topic. It is well-known that the water-splitting voltage is limited by a theoretical potential of 1.23 V of oxygen evolution reaction (OER). Recently, a new electrolytic method using iodide oxidation reaction (IOR) instead of OER has been proposed to produce valuable chemical iodine and hydrogen efficiently by a reduced operating voltage. In this work, we found that the graphite-based materials with a delocalized p electron system exhibited fast charge transfer with physically adsorbed iodide ions, thus revealing desirable IOR catalytic activity. The carbon fiber paper with a graphite structure was chosen as the catalyst and exhibited the onset potential of 0.54V (vs. RHE) for IOR, which is close to the standard potential of iodide oxidation. Also, the CFP demonstrated a minimum Tafel slope of 47.78 mV/dec in the electrochemical reaction with significant stability at the current density of 10 mA/cm2 for over 18 hours. Moreover, in a two-electrode system, a cell voltage of only 0.59 V was required to provide a current density of 10 mA/cm2 for the IOR and hydrogen evolution reaction (HER). Based on energy costs, our HER and IOR system can reduce energy consumption by 65% compared to conventional OER-based water electrolysis. The overall results indicate that our findings pave a new route to facilitate the industrial application of hydrogen production via electrochemical reactions.

李洛妤

李洛妤 Lo-Yu Lee
b901116@gmail.com
Tunghai University

張舒婷

張舒婷 Shu-Ting Chang
judychang950@gmail.com
Tunghai University

Singh Anupriya

Singh Anupriya
anupriyas962@gmail.com
Tunghai University

29 Jun. 2022, our work “Studies of High-Membered Two-Dimensional Ruddlesden-Popper Cs7Pb6I19 Perovskite Nanosheets via Kinetically Controlled Reactions” has been accepted by Mater. Horiz.

Studies of High-Membered Two-Dimensional Ruddlesden-Popper Cs7Pb6I19 Perovskite Nanosheets via Kinetically Controlled Reactions

Yi-Chia Chen, Kuan-Chang Wu, Hsin-An Chen, Wen-Hui Chu, Swathi M. Gowdru, Jou-Chun Lin, Bi-Hsuan Lin, Mau-Tsu Tang, Chia-Che Chang, Ying-Huang Lai, Tsung-Rong Kuo, Cheng-Yen Wen, Di-Yan Wang*

Mater. Horiz. 2022, just accepted.

Two-dimensional (2D) all-inorganic Ruddlesden-Popper (RP) perovskites Cs7Pb6I19 nanosheets (NSs) were successfully developed for the first time by employing a structural recrystallization process with additional passivation of small organic sulfide molecules. The structure of Cs7Pb6I19 NSs are confirmed by powder X-ray diffraction measurements, atomically-resolved STEM measurements and atomic force microscopic (AFM) studies. Cs7Pb6I19 NSs with a specific n value of 6 exhibit an unique absorption and emission spectra with intense excitons at 560 nm due to quantum confinement effects in 2D perovskite slabs. The formation mechanisms of 2D Cs7Pb6I19 NSs and 3D γ-CsPbI3 phases were investigated by in-situ photoluminescence (PL) spectroscopy and the activation energies of their formation reactions were calculated to be 151 kJ/mol and 95.3 kJ/mol, respectively. The phase stability of 2D Cs7Pb6I19 NSs can be maintained at temperatures below 14 oC for more than 4 weeks. The overall results indicate that 2D Cs7Pb6I19 NSs demonstrate unique optical properties and structural stability compared with other 3D perovskite materials. We have opened a new path to the future discovery of 2D perovskite structure with metastable phases by using this recrystallization method and the assistance of sulfur-derived organic molecules.

20 May. 2022, our Review Article “Electrochemical Reactions Towards the Formation of Heteroatomic Bonds beyond CO2 and N2 Reduction” has been accepted by Sustainable Energy & Fuels

20 May. 2022, our Review Article “Electrochemical Reactions Towards the Formation of Heteroatomic Bonds beyond CO2 and N2 Reduction” has been accepted by Sustainable Energy & Fuels

Shivaraj B. Patil and Di-Yan Wang*

Abstract

Contemporary, electrocatalytic carbon dioxide reduction (CO2RR) and nitrogen reduction reaction (NRR) have gained enormous attention as they are recognised as green and sustainable alternatives for production of various value-added fossil fuels and ammonia (NH3), respectively. Recently, prodigious efforts have been devoted in exploring different catalysts, different products while trying to understand the reaction mechanisms by detecting intermediates using in-situ techniques and density functional theory (DFT) calculations. Currently, the research focus is shifting from obtaining C1 compounds to C2+ compounds on CO2RR and producing NH3 from nitrate (NO3ˉ). Herein, we have summarized various reaction mechanisms reported for producing different compounds including C–C, C–H, and N–H bond formation on CO2RR and NRR. Factors affecting the formation of different compounds on CO2RR is resourcefully illustrated. Furthermore, electrocatalytic formation of heteroatomic C–N bond is exemplified along with reaction mechanisms. Finally, we presented our view on challenges and opportunities in heteroatomic bond formation. This perspective may ignite robust research in developing potential electrochemical systems with dynamic catalysts beyond C–H, N–H, and C–C bond formation.