Three‐dimensional Porous Palladium Foam‐like Nanostructures as Electrocatalysts for Glucose Biofuel Cells

Abstract

Three-dimensional (3D) porous palladium( Pd) nanostructures are electrodeposited by using the improved hydrogen templatep rotocol, involving ak ey step of the potential pulse.I nc ontrast to the conventional porous Pd catalysts, which are achieved by adopting the potentiostatic methodi n the reduction process,t hese 3D frameworkse xhibit au nique fractal morphology and more-abundant electrochemical surface area. Fort he application in implantableg lucose biofuel cells,t he 3D porousP dnanocatalysts show sufficient opencircuit potential (0.650 AE 0.005 V), high power density (5.7 AE 0.4 mWcm À2 ), and satisfyingl ong-term stability (< 10 %d egradation 30 days). This new procedure yields benefits such as rapid fabrication, mild conditions,p ure productsw ith au nique3 Dp orous structure,a nd the identical preparation technologyf or both the anode and cathode.Glucoseb iofuel cells (GBFCs) are currently attracting increasingi nterest because of the renewable gain of the fuel sources,t he wide prospect of implantation, and the environmentallyf riendly products.[1] To fully attain these advantages, the development of variouse lectrode materials has brought wide attention. Thee lectrodes in GBFCs are usually classified into two kinds:e nzymee lectrodes and non-enzymatic electrodes.[2] Non-enzymatic electrodes introduce advantages with respectt oc onquering the inherent defects of the enzymee lectrodes,s uch as quality instability, complicated immobilization, criticalo perating conditions,e tc.[3] In the recent literature,t he favorable properties of metallic nanostructures (high conductivity,l arge surface areas,a nd remarkable anti-poisoning activity) bode well for their applications in non-enzymatic GBFCs. [4] Recent progress furtherp roves that exactly controlling the size,s hape,a nd composition of the metallic catalysts could adjustt heir electrocatalytic properties,i mprove their performances,a nd provide them ab road opportunity to application in biology,m edicine,e nergy,a nd other fields.[5] Porous metallic catalysts become promising candidates as electrocatalysts of non-enzymatic GBFCs on account of their advanced electrical conductivity and abundant active area. In recentd ecades,p orous metal nanocatalysts of nickel, copper, silicon, tin, and silverh ave been electrodeposited by the hydrogent emplatem ethod. Unexpectedly,s ome conventional porous electrodes are frequently observed ad ecrease of the accessible surface areai nf ast, diffusion-controlled reactions, due to their unutilized morphology, which could lead to an intrinsico hmic resistance,m ass-transfer limitations,a nd potential hydrophobicity. [6,7] At present,the recognized efficient porous catalysts should have appropriate characteristics both at micrometer and nanometer dimensions. [8] With the aim to obtain the catalysts with optimized morphology and advanced active surface area, herein we evolved the improved hydrogen template electrodeposition by adopting ap otential pulse step methodi nt he reduction process to prepare the 3D palladium( Pd) ...

Electrocatalytic and Electroanalytic Investigation of Carbohydrates Oxidation on Gold-Based Nanocatalysts in Alkaline and Neutral pHs

“…Otherwise, the nature of the reaction product can no longer be extended a priori to other aqueous media. Given the great interest of metallic nanoparticles at pHs close to biological conditions for sensing or other "abiotic" purposes, 33,34,[52][53][54][55][56][57][58] we subsequently turned our spectroelectrochemical apparatus out to elucidate the nature of the reaction product. Compared to the investigations in a "relatively clean electrolyte" that is basic NaOH solution, the translation of spectroelectrochemistry in pH close to 7 is prohibitively challenging with added factors such as the low activity of metals toward organics electrooxidation and the presence of species such as phosphates which can interfere since they have vibration bands in the considered spectral domain.…”

Body-worn enzymatic biofuel cell with automated pencil drawn bioelectrodes for energy harvesting from human sweat

“…The important aspect of wearable electronics is that they should be of single-use to prevent inflammation risks [5]. The majority of these wearable devices are realized using organic and inorganic polymeric materials [6], novel metallic substrates [7], and emerging nanomaterials [8] on flexible polymer platforms [9]. Consequently, this cutting-edge technology has limitations such as costly electrode materials, complex fabrication procedures, need for expensive equipment, labor-intensive, power sources * Author to whom any correspondence should be addressed.…”

Nanostructured Inorganic Materials at Work in Electrochemical Sensing and Biofuel Cells

“…Several analogues and/or prototypes of abiotically catalyzed glucose fuel cells utilizing nanoscale or microscale materials were presented within the last decade [189,195,196,[198][199][200], in some cases incorporated with enzymes [201,202]. A compilation of recent glucose-based fuel cells operated in either close-biological conditions or alkaline/acidic ones can be found in Reference [203].…”

“…Various strategies for enzymatic electrode elaboration have been developed by different groups leading to efficient performances in vitro [30,[175][176][177][178][179][180][181] (from 1 to over 1000 µW·cm -2 ) and in those implanted in living organisms [124,[182][183][184][185][186][187][188]. Aiming to provide larger specific surface areas and a higher density of surface active sites, different methods have been developed to substitute one of the electrodes, mostly the anode, with an abiotic one, leading to the concept of the hybrid biofuel cell (hBFC) [180,[189][190][191], and in some cases, all the electrodes are substituted by abiotic catalysts [174,181,[192][193][194][195][196].…”