@article{14828,
  abstract     = {Production of hydrogen at large scale requires development of non-noble, inexpensive, and high-performing catalysts for constructing water-splitting devices. Herein, we report the synthesis of Zn-doped NiO heterostructure (ZnNiO) catalysts at room temperature via a coprecipitation method followed by drying (at 80 °C, 6 h) and calcination at an elevated temperature of 400 °C for 5 h under three distinct conditions, namely, air, N2, and vacuum. The vacuum-synthesized catalyst demonstrates a low overpotential of 88 mV at −10 mA cm–2 and a small Tafel slope of 73 mV dec–1 suggesting relatively higher charge transfer kinetics for hydrogen evolution reactions (HER) compared with the specimens synthesized under N2 or O2 atmosphere. It also demonstrates an oxygen evolution (OER) overpotential of 260 mV at 10 mA cm–2 with a low Tafel slope of 63 mV dec–1. In a full-cell water-splitting device, the vacuum-synthesized ZnNiO heterostructure demonstrates a cell voltage of 1.94 V at 50 mA cm–2 and shows remarkable stability over 24 h at a high current density of 100 mA cm–2. It is also demonstrated in this study that Zn-doping, surface, and interface engineering in transition-metal oxides play a crucial role in efficient electrocatalytic water splitting. Also, the results obtained from density functional theory (DFT + U = 0–8 eV), where U is the on-site Coulomb repulsion parameter also known as Hubbard U, based electronic structure calculations confirm that Zn doping constructively modifies the electronic structure, in both the valence band and the conduction band, and found to be suitable in tailoring the carrier’s effective masses of electrons and holes. The decrease in electron’s effective masses together with large differences between the effective masses of electrons and holes is noticed, which is found to be mainly responsible for achieving the best water-splitting performance from a 9% Zn-doped NiO sample prepared under vacuum.},
  author       = {Kiran, Gundegowda Kalligowdanadoddi and Singh, Saurabh and Mahato, Neelima and Sreekanth, Thupakula Venkata Madhukar and Dillip, Gowra Raghupathy and Yoo, Kisoo and Kim, Jonghoon},
  issn         = {2574-0962},
  journal      = {ACS Applied Energy Materials},
  keywords     = {Electrical and Electronic Engineering, Materials Chemistry, Electrochemistry, Energy Engineering and Power Technology, Chemical Engineering (miscellaneous)},
  number       = {1},
  pages        = {214--229},
  publisher    = {American Chemical Society},
  title        = {{Interface engineering modulation combined with electronic structure modification of Zn-doped NiO heterostructure for efficient water-splitting activity}},
  doi          = {10.1021/acsaem.3c02519},
  volume       = {7},
  year         = {2024},
}

@article{12227,
  abstract     = {Polydicyclopentadiene (pDCPD), a thermoset with excellent mechanical properties, has enormous potential as a lightweight, tough, and stable matrix material owing to its highly cross-linked macromolecular network. This work describes generating pDCPD-based foams and hierarchically porous carbons derived therefrom by combining ring-opening metathesis polymerization (ROMP) of DCPD, high internal phase emulsions (HIPEs) as structural templates, and subsequent carbonization. The structure and function of the carbon foams were characterized and discussed in detail using scanning electron, transmission electron, or atomic force microscopy (SEM, TEM, AFM), electron energy-loss spectroscopy (TEM-EELS), N2 sorption, and analyses of electrical conductivity as well as mechanical properties. The resulting materials exhibited uniform, shape-retaining shrinkage of only ∼1/3 after carbonization. No structural failure was observed even when the pDCPD precursor foams were heated to 1400 °C. Instead, the high porosity, void size, and 3D interconnectivity were fully preserved, and the void diameters could be adjusted between 87 and 2.5 μm. Moreover, foams have a carbon content >97%, an electronic conductivity of up to 2800 S·m–1, a Young’s modulus of up to 2.1 GPa, and a specific surface area of up to 1200 m2·g–1. Surprisingly, the pDCPD foams were carbonized into shapes other than monoliths, such as 10’s of micron thick membranes or foamy coatings adhered to a metal foil or grid substrate. The latter coatings even adhere upon bending. Finally, as a use case, carbonized foams were applied as porous cathodes for Li–O2 batteries where the foams show a favorable combination of porosity, active surface area, and pore size for outstanding capacity.},
  author       = {Kovačič, Sebastijan and Schafzahl, Bettina and Matsko, Nadejda B. and Gruber, Katharina and Schmuck, Martin and Koller, Stefan and Freunberger, Stefan Alexander and Slugovc, Christian},
  issn         = {2574-0962},
  journal      = {ACS Applied Energy Materials},
  keywords     = {Electrical and Electronic Engineering, Materials Chemistry, Electrochemistry, Energy Engineering and Power Technology, Chemical Engineering (miscellaneous)},
  number       = {11},
  pages        = {14381--14390},
  publisher    = {American Chemical Society},
  title        = {{Carbon foams via ring-opening metathesis polymerization of emulsion templates: A facile method to make carbon current collectors for battery applications}},
  doi          = {10.1021/acsaem.2c02787},
  volume       = {5},
  year         = {2022},
}