Nano-Porous Electro-Catalyst with Textured Surface Active Pd-Pt Islands for Efficient Methanol Tolerant Oxygen Reduction Reaction

Abstract

Herein, we report a simple and elegant aqueous synthesis of Pd100‐xPtx (x=5, 10, 15 and 20) nano‐porous structures (NPoS) derived from Pd100‐xMn2x (x=5, 10, 15 and 20) nano‐alloys. Pd100‐xPtx/C NPoS exhibit enhanced oxygen reduction reaction (ORR) activity along with higher retention of figure of merit in the presence of methanol compared to HiSPEC Pt/C catalyst. The ORR mass and specific activity values of Pd100‐xPtx/C NPoS are high and exceed the U.S. department of energy (DOE) 2017–2020 targets. The enhanced methanol tolerance and ORR activity of Pd100‐xPtx/C NPoS is attributed to their unique surface active Pd−Pt islands on nano‐porous Pd. Direct methanol fuel cell performance studies employed using Pd85Pt15/C NPoS as cathode material (0.4 mgPt/cm2) and HiSPEC PtRu/C NPs as anode material (0.2 mgPt/cm2) shows improved direct methanol fuel cell (DMFC) single cell activity at low Pt loading and the results are presented.

Shape-tuned, surface-active and support-free silver oxygen reduction electrocatalyst enabled high performance fully non-PGM alkaline fuel cell

“…To reveal this, the number of electrons transferred and percentage of HO 2 − intermediates formed during ORR process need to be estimated using the collection efficiency, disk and ring currents. To start with, average collection efficiency was calculated using potassium ferricyanide system as reported in our previous work 36 using the eqn (4) , where, CE refers to average collection efficiency, I R refers to the ring current and I D refers to the disk current respectively. The efficiency of the ORR process or its mechanism can be justified from the number of electrons ( n e ) transferred during ORR process and was calculated from the eqn (5) , where, n e is the number of electrons transferred per O 2 molecule during ORR process, I R is the ring current, I D is the disk current and CE is the average collection efficiency respectively.…”

“…For convenience, the potentials are converted to reversible hydrogen electrode (RHE) and accordingly labelled in graphs. LSV-RRDE measurements, collection efficiency (of 0.34) and number of electrons transferred during ORR process were calculated as reported in our previous work 36 using 0.5 M KOH electrolyte. The scan rate for CV is 50 mV s −1 and for LSV-RRDE is 5 mV s −1 .…”

Captivating nano sensors for mercury detection: a promising approach for monitoring of toxic mercury in environmental samples

“…Particularly for detecting toxic heavy metal ions like mercury, there's a signicant demand for precise sensing tools because even at low quantities, they are harmful. 46 Nanosensors designed for mercury detection employ intricate mechanisms connecting the unique characteristics of nanomaterials to detect mercury at exceptionally low concentrations, oen requiring minimal setup with advantages of specic and selective response based on the aggregation and morphology transition and SERS detection. [47][48][49] Surface functionalization signicantly enhances the affinity and selectivity of these nanomaterials towards mercury ions.…”