Dual Doping of MoP with M Mn,Fe and S to Achieve High Hydrogen Evolution Reaction Activity in Both Acidic and Alkaline Media

Rational design of cost effective, high performance and stable hydrogen evolution reaction HER electrocatalysts in both acidic and alkaline media holds the key to the future hydrogen based economy. Herein, we introduce an effective approach of simultaneous non metal S and metal Fe or Mn doping of MoP to achieve excellent HER performance at different pH. The catalysts show remarkable overpotentials at 10 mA cm 2 of only 65 and 68 mV in 0.5 M H2SO4, and 50 and 51 mV in 1.0 M KOH, respectively, as well as much higher turnover frequencies compared to undoped MoP. Furthermore, the catalysts exhibit outstanding long term stability at a fixed current of 10 mA cm 2 for 40 h. The effects of both dopants, such as electronic structure modification and enhancement of the intrinsic activity, increase of the electrochemically active surface area, and formation of coordinatively unsaturated edge sites, act cooperatively to accelerate the HER at both pH media. Additionally, the presence of oxophilic Mn and Fe at the surface results in Mn or Fe oxide hydroxide species that promote the dissociation of water molecules in alkaline electrolyte. This work introduces a facile and effective design principle that could pave the way towards engineering highly active HER catalysts for a wide pH range

Metal carboxyphosphonates-based electrocatalysts

Co1-xFex-HPAA metal phosphonates were prepared and pyrolyzed under N2 and H2/Ar flows. The resulting powders were structural and electrochemically characterized by XRD and CV, respectively. The obtained materials possess different structures depending on the temperature and pyrolysis atmosphere. Samples pyrolized in N2 at 1000 ºC are monophasic diphosphates, while phosphides form in H2/Ar at 850 ºC.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Single and solid solutions metal carboxyphosphonates as precursors for phosphorous-containing electrocatalysts

Co1-xFex-HPAA metal phosphonates were prepared and pyrolyzed under N2 and H2/Ar flows. The result-ing powders were structural and electrochemically characterised by XRD and CV, respectively. The ob-tained materials possess different structures depending on the temperature and pyrolysis atmosphere. Samples pyrolized in N2 at 1000 ºC are monophasic diphosphates, while phosphides form in H2/Ar at 850 ºC. Cyclic voltammetry studies indicate that the Co0.5Fe0.5HPAA sample, pyrolized in H2/Ar, exhibits the best behaviour, but further studies are needed to fully understand the role of graphene oxide and pyrazine.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec