Publications

Aiming to transition towards sustainable design processes, plasma doping methods have been investigated as ultra-fast and solvent-free alternatives to chemical doping strategies. Despite their advantages, the current state-of-the-art plasma-doped materials present low doping percentages. Consequently, their acceptance as a replacement to conventional methods is still disfavoured. In this work, we propose a change in the paradigm by presenting a new approach termed high-performance plasma doping (HPPD) capable of intensively doping material lattices. To do so, HPPD exploits the higher number of available sites in vacancy-engineered materials for introducing dopants through non-thermal plasma (NTP) treatment. For this purpose, hydroxyapatite (HAp) is presented as a representative case example of successful HPPD. Thus, HAp disks with OH- lattice vacancies are prepared and treated for short times with NTP. All the HPPD samples are oxygen-doped successfully, displaying conductivity enhancement of up to one order of magnitude. In addition, doping for the entire material bulk is achieved, reaching a doping replacement efficiency of 50%. The proposed mechanism, based on oxygen diffusion through the OH- HAp columns, is corroborated through density functional theory (DFT) calculations. Results reveal the key role of lattice vacancies as charge imbalances, exercising an electronic pull on reactive gas species. Further assessment of the HPPD HAp is done through catalytic CO2 conversion reactions. Thus, the synthesis of C1-C3 products (including ethanol and formic acid, among others) from CO2 under mild conditions (150 degrees C and 6 bar of CO2) is achieved, realizing a total yield of 537.85 +/- 3.40 mu mol gc-1. Finally, the implications of HPPD and its extension towards other materials are discussed and highlighted by performing a state-of-the-art comparison.

JTD Keywords: Co2, Congo red, Conversion, Nanoparticles, Oxide, Photocatalytic degradation, Sites, Surface, Tio2

JTD Keywords: added value chemicals, amino-acids, catalytic-hydrogenation, climate, design, electrochemical reduction, electroreduction, green co2 conversion to ethanol, nitrogen, photocatalytic reduction, polarized hydroxyapatite, recycling co2, sea-level, Acetone, Added value chemicals, Added-value chemicals, C-c coupling, Calcium apatites, Carbon dioxide, Carbon-dioxide, Co 2 reduction, Co2 reduction, Ethanol, Green co2 conversion to ethanol, Hard tissues, Hydroxyapatite, Mixtures, Morphology, Morphology and composition, Naturally occurring, Organic carbon, Phosphate minerals, Polarized hydroxyapatite, Recycling co2

Water contamination from industrial and anthropogenic activities is nowadays a major issue in many countries worldwide. To address this problem, efficient water treatment technologies are required. Recent efforts have focused on the development of self-propelled micromotors that provide enhanced micromixing and mass transfer by the transportation of reactive species, resulting in higher decontamination rates. However, a real application of these micromotors is still limited due to the high cost associated to their fabrication process. Here, we present Fe2O3-decorated SiO2/MnO2 microjets for the simultaneous removal of industrial organic pollutants and heavy metals present in wastewater. These microjets were synthesized by low-cost and scalable methods. They exhibit an average speed of 485 ± 32 μm s–1 (∼28 body length per s) at 7% H2O2, which is the highest reported for MnO2-based tubular micromotors. Furthermore, the photocatalytic and adsorbent properties of the microjets enable the efficient degradation of organic pollutants, such as tetracycline and rhodamine B under visible light irradiation, as well as the removal of heavy metal ions, such as Cd2+ and Pb2+.

JTD Keywords: Micromotors, Photocatalytic, Water purification, Fenton, Magnetic control, Iron oxide, Manganese oxide