Hydrogen energy, as a strategic emerging industry, is an essential part of the future national energy system and decarbonization energy carrier for end users. Hydrogen generation via water electrolysis benefits large-scale renewable energy consumption and the national energy structure transformation. To fulfill the need for large-scale, highly efficient, and long-life water electrolyzers, integrating interfacial engineering concepts and manufacturing methods to enhance nanotechnology industrialization is crucial. Based on interfacial engineering principles, this review summarizes recent progress on self-supported electrodes, with a focus on improving the stability of the electrode structure and electrocatalytic activity, and examines the influence of microstructure on catalytic performance, particularly at three key interfaces (catalytic sites/substrate interface, interface among catalysts, and electrode/electrolyte interface). Moreover, we discuss strategies for developing self-supported catalytic electrodes with high activity and stability.
WANG Peican. Interface engineering of self-supported electrode for electrochemical water splitting[J]. Energy Storage Science and Technology, 2022, 11(6): 1934-1946
Fig. 4
The schmatic diagrams of three typical water-splitting electrolyzers: (a) Alkaline water electrolyzer;(b) Proton exchange membrane water electrolyzers; (c) Alkaline exchange membrane water electrolyzers[28]
Fig. 9
(a) The schematic diagram of fabrication of MoS2/NiCo-LDH; (b)-(c) The HER free energy of the edge of MoS2 and interface of Ni(OH)2/MoS2[43]; (d) Fabrication of Ni(OH)2/MoS2[45]; (e) Fabrication of Ni3S2/VO2[46]
Fig. 10
(a) The low-magnification SEM image of NiFe/Ni/Ni; (b) The high-magnification SEM imageof NiFe/Ni/Ni; (c) OER performance; (d) HER performance[53]
除此之外,还可以通过设计电极结构来实现传质强化。Li等[54]报道了一种肺泡结构的催化电极,如图11(a)所示,该结构能够实现气相产物与液相反应物分离。该肺泡结构电极的内侧为聚乙烯薄膜,外侧为金薄膜支撑的NiFeO x 催化层。在其中,聚乙烯薄膜能够有效防止电解液进入到电极内部的空腔,同时能确保催化层的NiFeO x 催化层被电解液充分浸润。该结构从而能够形成充足的三相活性位点。另外,该结构还能有利于在电极表面原位产生的气体气泡快速进入气相空腔,实现快速脱附,同时,有效降低形成气泡所需的额外能量,实现传质强化目的。为此该结构的催化电极表现出远高于传统结构电极[图11(b)]的催化活性,其在电流密度为10 mA/cm2时,所需的析氧过电位仅仅为190 mV,性能优于现有研究报道。
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电解水电解槽示意图<sup>[<xref ref-type="bibr" rid="R15">15</xref>]</sup>The illustration of the water electrolyzer<sup>[<xref ref-type="bibr" rid="R15">15</xref>]</sup>Fig. 1
... [23];(b) 氧析出反应火山曲线[2]<strong>(a) The reaction mechanism of OER</strong><sup>[<xref ref-type="bibr" rid="R23">23</xref>]</sup>;<strong>(b) The volcano plot of OER</strong><sup>[<xref ref-type="bibr" rid="R2">2</xref>]</sup>Fig. 3
... Zhang等[43]报道了一种Ni(OH)2与MoS2复合的催化电极(Ni(OH)2/MoS2)用于催化析氢[图9(a)].其中Ni(OH)2纳米颗粒(5~10 nm)均匀地负载在MoS2纳米片表面形成支撑结构复合物.透射电子显微镜(TEM)结果表明在MoS2纳米片表面引入Ni(OH)2纳米粒子将增大MoS2的层间距,从而暴露出更多硫活性边缘.X射线光电子能谱(XPS)测试结果表明引入Ni(OH)2后,Ni(OH)2/MoS2中S 2p的结合能负移,说明电子从Ni(OH)2转移到MoS2,证明两组分之间存在强电子作用.DFT结果表明在两组分的界面处,Ni(OH)2易于和O结合而MoS2易于与H结合[图9(b)、(c)].因此,水分子首先吸附在Ni(OH)2上并发生解离,同时解离的氢被吸附在临近的MoS2活性位点,最后两个吸附态氢结合生成H2.因此,MoS2与Ni(OH)2的协同作用能显著加快HER动力学.另外,Niu等人[44]通过两步电沉积在泡沫镍上原位生长多级结构的FeOOH/Ni(OH)2,Ni与Fe之间的协同作用使得FeOOH/Ni(OH)2具有高催化活性,电流密度为40 mA/cm2时所需析氧过电位仅为207 mV.三种典型的两组分化合物组合的复合物结构示意图 <strong>(a)</strong> 支撑结构;<strong>(b)</strong> 异质结构;<strong>(c)</strong> 核壳结构<sup>[<xref ref-type="bibr" rid="R35">35</xref>]</sup>Schematic diagram of three typical components with two compositions: (a) Supported structure; (b) Heterostructure; (c) Core-shell structureFig. 8<strong>(a) MoS<sub>2</sub>/NiCo-LDH</strong>复合材料合成示意图;<strong>(b)</strong>~<strong>(c) MoS<sub>2</sub></strong> 边缘和<strong>Ni(OH)<sub>2</sub>/MoS<sub>2</sub></strong> 的<strong>HER</strong>自由能<sup>[<xref ref-type="bibr" rid="R43">43</xref>]</sup>;<strong>(d) Ni(OH)<sub>2</sub>/MoS<sub>2</sub></strong> 合成示意图<sup>[<xref ref-type="bibr" rid="R45">45</xref>]</sup>;<strong>(e) Ni<sub>3</sub>S<sub>2</sub>/VO<sub>2</sub></strong> 的合成示意图<sup>[<xref ref-type="bibr" rid="R46">46</xref>]</sup>(a) The schematic diagram of fabrication of MoS<sub>2</sub>/NiCo-LDH; (b)-(c) The HER free energy of the edge of MoS<sub>2</sub> and interface of Ni(OH)<sub>2</sub>/MoS<sub>2</sub><sup>[<xref ref-type="bibr" rid="R43">43</xref>]</sup>; (d) Fabrication of Ni(OH)<sub>2</sub>/MoS<sub>2</sub><sup>[<xref ref-type="bibr" rid="R45">45</xref>]</sup>; (e) Fabrication of Ni<sub>3</sub>S<sub>2</sub>/VO<sub>2</sub><sup>[<xref ref-type="bibr" rid="R46">46</xref>]</sup>Fig. 9
... [38]The schematic diagram of frabrication of Co(OH)<sub>2</sub> based electrode<sup>[<xref ref-type="bibr" rid="R38">38</xref>]</sup>Fig. 7<strong>2.2</strong> 催化剂内部界面
... [43];(d) Ni(OH)2/MoS2 合成示意图[45];(e) Ni3S2/VO2 的合成示意图[46](a) The schematic diagram of fabrication of MoS<sub>2</sub>/NiCo-LDH; (b)-(c) The HER free energy of the edge of MoS<sub>2</sub> and interface of Ni(OH)<sub>2</sub>/MoS<sub>2</sub><sup>[<xref ref-type="bibr" rid="R43">43</xref>]</sup>; (d) Fabrication of Ni(OH)<sub>2</sub>/MoS<sub>2</sub><sup>[<xref ref-type="bibr" rid="R45">45</xref>]</sup>; (e) Fabrication of Ni<sub>3</sub>S<sub>2</sub>/VO<sub>2</sub><sup>[<xref ref-type="bibr" rid="R46">46</xref>]</sup>Fig. 9
... Zhang等[43]报道了一种Ni(OH)2与MoS2复合的催化电极(Ni(OH)2/MoS2)用于催化析氢[图9(a)].其中Ni(OH)2纳米颗粒(5~10 nm)均匀地负载在MoS2纳米片表面形成支撑结构复合物.透射电子显微镜(TEM)结果表明在MoS2纳米片表面引入Ni(OH)2纳米粒子将增大MoS2的层间距,从而暴露出更多硫活性边缘.X射线光电子能谱(XPS)测试结果表明引入Ni(OH)2后,Ni(OH)2/MoS2中S 2p的结合能负移,说明电子从Ni(OH)2转移到MoS2,证明两组分之间存在强电子作用.DFT结果表明在两组分的界面处,Ni(OH)2易于和O结合而MoS2易于与H结合[图9(b)、(c)].因此,水分子首先吸附在Ni(OH)2上并发生解离,同时解离的氢被吸附在临近的MoS2活性位点,最后两个吸附态氢结合生成H2.因此,MoS2与Ni(OH)2的协同作用能显著加快HER动力学.另外,Niu等人[44]通过两步电沉积在泡沫镍上原位生长多级结构的FeOOH/Ni(OH)2,Ni与Fe之间的协同作用使得FeOOH/Ni(OH)2具有高催化活性,电流密度为40 mA/cm2时所需析氧过电位仅为207 mV.三种典型的两组分化合物组合的复合物结构示意图 <strong>(a)</strong> 支撑结构;<strong>(b)</strong> 异质结构;<strong>(c)</strong> 核壳结构<sup>[<xref ref-type="bibr" rid="R35">35</xref>]</sup>Schematic diagram of three typical components with two compositions: (a) Supported structure; (b) Heterostructure; (c) Core-shell structureFig. 8<strong>(a) MoS<sub>2</sub>/NiCo-LDH</strong>复合材料合成示意图;<strong>(b)</strong>~<strong>(c) MoS<sub>2</sub></strong> 边缘和<strong>Ni(OH)<sub>2</sub>/MoS<sub>2</sub></strong> 的<strong>HER</strong>自由能<sup>[<xref ref-type="bibr" rid="R43">43</xref>]</sup>;<strong>(d) Ni(OH)<sub>2</sub>/MoS<sub>2</sub></strong> 合成示意图<sup>[<xref ref-type="bibr" rid="R45">45</xref>]</sup>;<strong>(e) Ni<sub>3</sub>S<sub>2</sub>/VO<sub>2</sub></strong> 的合成示意图<sup>[<xref ref-type="bibr" rid="R46">46</xref>]</sup>(a) The schematic diagram of fabrication of MoS<sub>2</sub>/NiCo-LDH; (b)-(c) The HER free energy of the edge of MoS<sub>2</sub> and interface of Ni(OH)<sub>2</sub>/MoS<sub>2</sub><sup>[<xref ref-type="bibr" rid="R43">43</xref>]</sup>; (d) Fabrication of Ni(OH)<sub>2</sub>/MoS<sub>2</sub><sup>[<xref ref-type="bibr" rid="R45">45</xref>]</sup>; (e) Fabrication of Ni<sub>3</sub>S<sub>2</sub>/VO<sub>2</sub><sup>[<xref ref-type="bibr" rid="R46">46</xref>]</sup>Fig. 9
... Zhang等[43]报道了一种Ni(OH)2与MoS2复合的催化电极(Ni(OH)2/MoS2)用于催化析氢[图9(a)].其中Ni(OH)2纳米颗粒(5~10 nm)均匀地负载在MoS2纳米片表面形成支撑结构复合物.透射电子显微镜(TEM)结果表明在MoS2纳米片表面引入Ni(OH)2纳米粒子将增大MoS2的层间距,从而暴露出更多硫活性边缘.X射线光电子能谱(XPS)测试结果表明引入Ni(OH)2后,Ni(OH)2/MoS2中S 2p的结合能负移,说明电子从Ni(OH)2转移到MoS2,证明两组分之间存在强电子作用.DFT结果表明在两组分的界面处,Ni(OH)2易于和O结合而MoS2易于与H结合[图9(b)、(c)].因此,水分子首先吸附在Ni(OH)2上并发生解离,同时解离的氢被吸附在临近的MoS2活性位点,最后两个吸附态氢结合生成H2.因此,MoS2与Ni(OH)2的协同作用能显著加快HER动力学.另外,Niu等人[44]通过两步电沉积在泡沫镍上原位生长多级结构的FeOOH/Ni(OH)2,Ni与Fe之间的协同作用使得FeOOH/Ni(OH)2具有高催化活性,电流密度为40 mA/cm2时所需析氧过电位仅为207 mV.三种典型的两组分化合物组合的复合物结构示意图 <strong>(a)</strong> 支撑结构;<strong>(b)</strong> 异质结构;<strong>(c)</strong> 核壳结构<sup>[<xref ref-type="bibr" rid="R35">35</xref>]</sup>Schematic diagram of three typical components with two compositions: (a) Supported structure; (b) Heterostructure; (c) Core-shell structureFig. 8<strong>(a) MoS<sub>2</sub>/NiCo-LDH</strong>复合材料合成示意图;<strong>(b)</strong>~<strong>(c) MoS<sub>2</sub></strong> 边缘和<strong>Ni(OH)<sub>2</sub>/MoS<sub>2</sub></strong> 的<strong>HER</strong>自由能<sup>[<xref ref-type="bibr" rid="R43">43</xref>]</sup>;<strong>(d) Ni(OH)<sub>2</sub>/MoS<sub>2</sub></strong> 合成示意图<sup>[<xref ref-type="bibr" rid="R45">45</xref>]</sup>;<strong>(e) Ni<sub>3</sub>S<sub>2</sub>/VO<sub>2</sub></strong> 的合成示意图<sup>[<xref ref-type="bibr" rid="R46">46</xref>]</sup>(a) The schematic diagram of fabrication of MoS<sub>2</sub>/NiCo-LDH; (b)-(c) The HER free energy of the edge of MoS<sub>2</sub> and interface of Ni(OH)<sub>2</sub>/MoS<sub>2</sub><sup>[<xref ref-type="bibr" rid="R43">43</xref>]</sup>; (d) Fabrication of Ni(OH)<sub>2</sub>/MoS<sub>2</sub><sup>[<xref ref-type="bibr" rid="R45">45</xref>]</sup>; (e) Fabrication of Ni<sub>3</sub>S<sub>2</sub>/VO<sub>2</sub><sup>[<xref ref-type="bibr" rid="R46">46</xref>]</sup>Fig. 9
... [53](a) The low-magnification SEM image of NiFe/Ni/Ni; (b) The high-magnification SEM imageof NiFe/Ni/Ni; (c) OER performance; (d) HER performance<sup>[<xref ref-type="bibr" rid="R53">53</xref>]</sup>Fig. 10
除此之外,还可以通过设计电极结构来实现传质强化.Li等[54]报道了一种肺泡结构的催化电极,如图11(a)所示,该结构能够实现气相产物与液相反应物分离.该肺泡结构电极的内侧为聚乙烯薄膜,外侧为金薄膜支撑的NiFeO x 催化层.在其中,聚乙烯薄膜能够有效防止电解液进入到电极内部的空腔,同时能确保催化层的NiFeO x 催化层被电解液充分浸润.该结构从而能够形成充足的三相活性位点.另外,该结构还能有利于在电极表面原位产生的气体气泡快速进入气相空腔,实现快速脱附,同时,有效降低形成气泡所需的额外能量,实现传质强化目的.为此该结构的催化电极表现出远高于传统结构电极[图11(b)]的催化活性,其在电流密度为10 mA/cm2时,所需的析氧过电位仅仅为190 mV,性能优于现有研究报道. ...
... [53]Fig. 10
除此之外,还可以通过设计电极结构来实现传质强化.Li等[54]报道了一种肺泡结构的催化电极,如图11(a)所示,该结构能够实现气相产物与液相反应物分离.该肺泡结构电极的内侧为聚乙烯薄膜,外侧为金薄膜支撑的NiFeO x 催化层.在其中,聚乙烯薄膜能够有效防止电解液进入到电极内部的空腔,同时能确保催化层的NiFeO x 催化层被电解液充分浸润.该结构从而能够形成充足的三相活性位点.另外,该结构还能有利于在电极表面原位产生的气体气泡快速进入气相空腔,实现快速脱附,同时,有效降低形成气泡所需的额外能量,实现传质强化目的.为此该结构的催化电极表现出远高于传统结构电极[图11(b)]的催化活性,其在电流密度为10 mA/cm2时,所需的析氧过电位仅仅为190 mV,性能优于现有研究报道. ...
3
... 除此之外,还可以通过设计电极结构来实现传质强化.Li等[54]报道了一种肺泡结构的催化电极,如图11(a)所示,该结构能够实现气相产物与液相反应物分离.该肺泡结构电极的内侧为聚乙烯薄膜,外侧为金薄膜支撑的NiFeO x 催化层.在其中,聚乙烯薄膜能够有效防止电解液进入到电极内部的空腔,同时能确保催化层的NiFeO x 催化层被电解液充分浸润.该结构从而能够形成充足的三相活性位点.另外,该结构还能有利于在电极表面原位产生的气体气泡快速进入气相空腔,实现快速脱附,同时,有效降低形成气泡所需的额外能量,实现传质强化目的.为此该结构的催化电极表现出远高于传统结构电极[图11(b)]的催化活性,其在电流密度为10 mA/cm2时,所需的析氧过电位仅仅为190 mV,性能优于现有研究报道. ...
... [54]Schematic representation of the OER gas delivery path for (a) an alveolus-like polyethylene structure and (b) a flat structure<sup>[<xref ref-type="bibr" rid="R54">54</xref>]</sup>Fig. 11<strong>2.4</strong> 大面积自支撑催化电极的制备