“…[180] The authors synthesized this CE via a simple one-step solution route to introduce nanowalls and graphene-like layers as active CEs in DSSC. [181] SnO 2 possessed high electron mobility (125-250 cm 2 V −1 s −1 ) while the Ta doping further enhanced the electron conductivity and mobility of SnO 2 by increasing the electron concentration, as confirmed by DFT calculations. [181] The Ta-doped First-principles calculations are employed to understand the high catalytic activity of Sn 1-…”
Section: Functional Doping or Structural Designsupporting
Recently, there is an urgent need for alternative energy resources due to the nonrenewable nature of fossil fuels and the increasing CO 2 greenhouse gas emissions. The photovoltaic technologies which directly utilize the abundant and sustainable solar energy are critical. Among various photovoltaic devices (solar cells), dye-sensitized solar cells (DSSCs) have gained increasing attention due to their high efficiency and easy fabrication process in the past decade. The cathode is a critical part in DSSCs while the benchmark Pt cathode suffers from high cost and scarcity. Thus, the development of alternative Pt-free cathodes have attracted numerous attentions to heighten the cost competitiveness of DSSCs. Among various cathodes, metal oxides are of growing interest due to their superior activity, robust stability and low cost. Simple oxides such as WO 3 and SnO 2 are used as cathodes for DSSCs. Considering the fixed atomic environment in simple oxides, complex oxides are more attractive as cathodes because of their more flexible physical and chemical properties. This review attempts to present the rational design of simple/complex metal oxide-based cathodes in DSSCs and then to provide useful guidance for the future design and development of Pt-free cathodes. The demonstrated design strategies can be extended to other electrocatalysis-based applications.Received: ((will be filled in by the editorial staff))Revised: ((will be filled in by the editorial staff))
“…[180] The authors synthesized this CE via a simple one-step solution route to introduce nanowalls and graphene-like layers as active CEs in DSSC. [181] SnO 2 possessed high electron mobility (125-250 cm 2 V −1 s −1 ) while the Ta doping further enhanced the electron conductivity and mobility of SnO 2 by increasing the electron concentration, as confirmed by DFT calculations. [181] The Ta-doped First-principles calculations are employed to understand the high catalytic activity of Sn 1-…”
Section: Functional Doping or Structural Designsupporting
Recently, there is an urgent need for alternative energy resources due to the nonrenewable nature of fossil fuels and the increasing CO 2 greenhouse gas emissions. The photovoltaic technologies which directly utilize the abundant and sustainable solar energy are critical. Among various photovoltaic devices (solar cells), dye-sensitized solar cells (DSSCs) have gained increasing attention due to their high efficiency and easy fabrication process in the past decade. The cathode is a critical part in DSSCs while the benchmark Pt cathode suffers from high cost and scarcity. Thus, the development of alternative Pt-free cathodes have attracted numerous attentions to heighten the cost competitiveness of DSSCs. Among various cathodes, metal oxides are of growing interest due to their superior activity, robust stability and low cost. Simple oxides such as WO 3 and SnO 2 are used as cathodes for DSSCs. Considering the fixed atomic environment in simple oxides, complex oxides are more attractive as cathodes because of their more flexible physical and chemical properties. This review attempts to present the rational design of simple/complex metal oxide-based cathodes in DSSCs and then to provide useful guidance for the future design and development of Pt-free cathodes. The demonstrated design strategies can be extended to other electrocatalysis-based applications.Received: ((will be filled in by the editorial staff))Revised: ((will be filled in by the editorial staff))
“…Generally,t he Db and of carbon indicates defects and disordered portions, whereas the Gb and represents the ordered graphitic crystallites of carbon. [31,32] The intensity ratio of the Da nd Gb ands (I D /I G )i sa bout 0.93, which indicates amorphous carbon in the HCF/Mn 3 O 4 composite. The pore size distribution, specific surface area, and pore volumeofthe composite wered etermined from the N 2 adsorption/desorption isotherms.A ss hown in Figure 2c,t he N 2 sorptioni sothermo f the HCF/Mn 3 O 4 composite shows at ype IV curve, which indicates the existence of substantial mesopores.…”
Section: Resultsmentioning
confidence: 99%
“…In addition, a D band at 1348 cm −1 and a G band at 1598 cm −1 is typical for carbon. Generally, the D band of carbon indicates defects and disordered portions, whereas the G band represents the ordered graphitic crystallites of carbon . The intensity ratio of the D and G bands ( I D / I G ) is about 0.93, which indicates amorphous carbon in the HCF/Mn 3 O 4 composite.…”
The practical applications of Mn O in lithium-ion batteries are greatly hindered by fast capacity decay and poor rate performance as a result of significant volume changes and low electrical conductivity. It is believed that the synthesis of nanoscale Mn O combined with carbonaceous matrix will lead to a better electrochemical performance. Herein, a convenient route for the synthesis of Mn O nanoparticles grown in situ on hollow carbon nanofiber (denoted as HCF/Mn O ) is reported. The small size of Mn O particles combined with HCF can significantly alleviate volume changes and electrical conductivity; the strong chemical interactions between HCF and Mn O would improve the reversibility of the conversion reaction for MnO into Mn O and accelerate charge transfer. These features endow the HCF/Mn O composite with superior cycling stability and rate performance if used as the anode for lithium-ion batteries. The composite delivers a high discharge capacity of 835 mA h g after 100 cycles at 200 mA g , and 652 mA h g after 240 cycles at 1000 mA g . Even at 2000 mA g , it still shows a high capacity of 528 mA h g . The facile synthetic method and outstanding electrochemical performance of the as-prepared HCF/Mn O composite make it a promising candidate for a potential anode material for lithium-ion batteries.
“…After the IrO 2 loading, the conductivity of 40IrO 2 /Co x Sn 1− x O 2 ( x = 0.1, 0.2, 0.3) is enhanced because of the excellent electrical conductivity of IrO 2 . However, the electrical conductivities of Co 0.3 Sn 0.9 O 2 and 40IrO 2 /Co 0.3 Sn 0.9 O 2 are lower than those of Co 0.2 Sn 0.8 O 2 and 40IrO 2 /Co 0.2 Sn 0.8 O 2 , which might be due to the increasing impurity scattering centres with the enhancement of Co contents that impede the electron transport, decrease the carrier mobility and reduce electrical conductivity [41].…”
Section: Resultsmentioning
confidence: 99%
“…Notably, the OER performance decreases when the Co-doping level reaches to the point x = 0.3. This could be attributed to the increasing impurity scattering centres with the enhancement of Co contents that impede the electron transport and decrease the carrier mobility, leading to the degradation of OER performance [41]. Figure 7.Polarization curves of single cells equipped with 40IrO 2 /Co x Sn 1− x O 2 ( x = 0, 0.1, 0.2, 0.3) and unsupported IrO 2 at 80°C.…”
SPE water electrolysis is a promising method of hydrogen production owing to its multiple strengths, including its high efficiency, high product purity and excellent adaptability. However, the overpotential of the oxygen evolution reaction process and consumption of Ir during charging in SPE water electrolysis will inevitably result in large energy loss and then high cost. Under these circumstances, we propose a novel 40IrO
2
/Co
x
Sn
(1−
x
)
O
2
(
x
= 0.1, 0.2, 0.3) anode catalyst, where the Co
x
Sn
(1−
x
)
O
2
support is synthesized by a hydrothermal method and IrO
2
is synthesized by a modified Adams fusion method. After modifying the component of Co
x
Sn
(1−
x
)
O
2
, the 40IrO
2
/Co
x
Sn
(1−
x
)
O
2
exhibits an increased specific surface area, electrical conductivity and surface active sites. Moreover, a single cell is fabricated by Pt/C as cathode catalyst, 40IrO
2
/Co
x
Sn
(1−
x
)
O
2
as anode catalyst and Nafion 117 membrane as electrolyte. The 40IrO
2
/Co
0.2
Sn
0.8
O
2
exhibits the lowest overpotential (1.748 V at 1000 mA cm
−2
), and only 0.18 mV h
−1
of voltage increased for 100 h durability test at 1000 mA cm
−2
. Consequently, Co
x
Sn
(1−
x
)
O
2
is a promising anode electrocatalyst support for an SPE water electrolyzer.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
