Double‐Layered NiO Photocathodes for p‐Type DSSCs with Record IPCE

Abstract

Dye-sensitized solar cells (DSSCs) have attracted considerable interest as a low cost and renewable means of harnessing solar energy.[1] In order to make these devices competitive with other photovoltaic technologies, many attempts have been made to increase the photoconversion efficiency. One concept is to combine an n-type TiO 2 -based photoanode with a p-type NiO-based photocathode, in a tandem configuration in order to capture more of the solar spectrum and improve the open-circuit potential (V OC ). [2,3] Complementary to the photoanode, a photoexcited dye injects a hole into the valence band of the NiO cathode, which travels to the FTO charge collector. The reduced dye is oxidized by the redox couple in the electrolyte which diffuses to the photoanode (tandem-DSSC) or passive counter electrode (p-DSSC) where the redox cycle is completed ( Figure S1). Therefore, the development of an efficient photocathode is one of the key elements in achieving an effective tandem-DSSC. Here we describe a NiO-based p-DSSC giving 64% incident photon-to-current efficiency (IPCE) and a short circuit current (J SC ) of 5.48 mAcm À2

Electrochemical characterization of NiO electrodes deposited via a scalable powder microblasting technique

“…5 Because of this interesting combination of electrical and optical properties, NiO x has been considered for energy storage applications, [6][7][8] in electrochromic devices as transparent electrode, 9-17 in optoelectronic devices as electron barrier, 18,19 for gas sensing, 20,21 and, more recently, in dye-sensitized solar cells (DSCs) as photoactive cathode. [22][23][24][25][26][27][28][29][30][31][32][33][34][35] The utilization of NiO x in such diverse applications has been accompanied by the development of various preparation methods and deposition techniques, aimed at producing NiO x -based materials with variable chemical composition, electrical resistivity, compactness and morphology. Examples include electrochemical deposition, 36 chemical vapor 37 and bath deposition, 38 spray pyrolysis, 39,40 sol-gel method, 14,23,25,41 hydrothermal synthesis, 29,42 and sputtering.…”

Spray-deposited NiO x films on ITO substrates as photoactive electrodes for p-type dye-sensitized solar cells

“…[3,4] Because of this interesting combination of electrical and optical properties, NiO x has been considered as active material for various applications like energy storage, [5,6] in electrochromic smart windows, [7][8][9][10][11] optoelectronic devices, [12] and, more importantly, in dye-sensitized solar cells (DSCs) as photoactive dye-sensitized mesoporous cathode. [13][14][15][16][17][18][19] The utilization of NiO x in such diverse applications has been accompanied by the development of various preparation methods and deposition techniques aimed at producing NiO x based materials with variable chemical composition, electrical resistivity, compactness and morphology for performance optimization. Most common examples include sputtering, [20] electrochemical deposition, [21] spray pyrolysis [22] or sol-gel method.…”

Application of a novel microwave plasma treatment for the sintering of nickel oxide coatings for use in dye-sensitized solar cells

“…NiO x films have been fabricated by various techniques which include spin coating, dipping, electrochemical deposition [17], magnetron sputtering [18][19][20] and sol-gel [21][22][23][24][25]. With the exception of electrochemical techniques, the other deposition methods require subsequent thermal treatments in order to enhance the density of the coatings [21][22][23][24][25][26], to obtain crystalline structure in the as deposited sputtered coatings [26] and to remove the binder in the case of sol-gel deposited coatings [21][22][23][24][25]. Typically sintering conditions of 300-450 °C for 30 to 60 minutes are reported [21][22][23][24][25].…”