Table 2 Techniques utilized by researchers as per literature in mitigating EM wave reflection of NW fabric-based EMI shields

Coating

 TPU-CNTs/Ti₃C₂T_x

Dip-coating

-

 ~ 43

The in-situ coating of the non-woven fabric with CNTs and MXene resulted in enhanced EM wave absorption due to enhanced conductivity, interaction of the EM waves with the high-density free electrons of the fabric, and permeableness

[51]

 Cotton@Cu@PDMS

Electroless plating + dip coating

-

110

The introduction of absorption loss (by Cu), interfacial polarization by Cu/CuO heterojunctions as well as fabric permeableness by the porous architecture of the non-woven enhanced EM waves absorption

[52]

 Waterborne polyurethane (WPU)@Ag/NWF/FeCo@rGO

Wet electroless deposition

-

77.1

The introduction of magnetic loss (by FeCo), dielectric loss (by FeCo & rGO) as well as enhanced permeableness by the porous architecture of the non-woven enhanced EM waves absorption

[53]

 WPU@Ag/NWF

Solution casting-based coating

-

72.5

Enhanced conductivity and multiple internal reflections followed by absorption

[53]

 Cotton fibers @Ag

Wet electroless deposition

 ~ 0

17 (Ag@CFs-10) & 111 (Ag@CFs-180)

Interfaces abound as well as the structure was permeable: The numerous reflections plus subsequent absorptions in the materials weakened EM waves

[19, 21]

 PET@Cu@Ag

Coating + plating

-

61

Due to the coated materials' excellent electrical conductivities, this behavior was linked to a higher reflection of EM waves

[54]

 PE@ polydopamine (PDA) (PP/PDA/AgNPs-50/PFDT-50)

In situ polymerization-coating + Ag coating

-

49

Enhanced conductivity and multiple internal reflections followed by absorption

[55]

 Cu/Ni@PET (MEFTEX 20)

‘Roll on roll’ coating

-

70

Increase in the number of layers as well metal coating resulting in reduced aperture area and enhanced EM wave absorption

[56]

 PP@Ni/Cu (SNW)

Metallic ion sputtered NW

 < 5

 > 40

Coating with Ni/Cu

[57]

 PET@Cu/Zn/Sn (CNW)

Metallic ion sputtered Nonwoven

 < 5

 > 50

Coating with Cu/Zn/Sn

[57]

 PP/rGO

Dip coating or impregnation

 < 2

-15

The coating of the non-woven fabric with rGO resulted in enhanced EM wave absorption due to enhanced permeableness

[58]

 Poly(m-phenylene isophthalamide) (PMIA)/Ag@PEDOT:PSS

Dip coating

 ~ 0

56.6

The coating of the non-woven fabric with Ag@PEDOT resulted in enhanced EM wave absorption due to enhanced permeableness

[59]

 PET/PPy (CNT + Ppy NW)

Knife over roller coating

-

14.1

The coating of the non-woven fabric with PPy resulted in enhanced EM wave absorption due to enhanced permeableness

[17]

 PAN-based CFs@Cu

Electroplating

-

70–90

The coating of the non-woven fabric with Cu resulted in enhanced EM wave absorption due to enhanced reflection loss within the fabric due to conduction

[60]

 PET/ Ni-based alloy(Ni–Fe)

Electroless plating

5%

99.98%

The coating of the non-woven fabric with Ni-based alloy resulted in enhanced EM wave absorption due to enhanced reflection loss within the fabric

[61]

 Viscose@Ag

Electroplating

 ~ 0

91

The coating of the non-woven fabric with Ag resulted in enhanced EM wave absorption due to enhanced internal multiple scattering absorption

[62]

In situ polymerization

 PET@Fe₃O₄/rGO@PANI/Ni–P (1-layer)

In situ polymerization and Ni–P electroless plating

 < 3

27

Enhanced dielectric and magnetic loss via Fe₃O₄/rGO@PANI/Ni–P in situ polymerization and plating leading to enhanced EM waves absorption

[63]

 PET@Fe₃O₄/rGO@PANI/Ni–P (2-layers)

In situ polymerization and Ni–P electroless plating

 < 3

42

Enhanced dielectric and magnetic loss via Fe₃O₄/rGO@PANI/Ni–P in situ polymerization and plating leading to enhanced EM waves absorption

[63]

 PET@Fe₃O₄/rGO@PANI/Ni–P (3-layers)

In situ polymerization and Ni–P electroless plating

 < 3

81

Enhanced dielectric and magnetic loss via Fe₃O₄/rGO@PANI/Ni–P in situ polymerization and plating leading to enhanced EM waves absorption

[63]

 PET (WO-ME150)@PPy

Dip coating-co-in situ polymerization

 < -7

-20

Enhanced R_L resulting in increase in absorption of EM waves

[64]

 PET/PANI

In situ polymerization com-dip coating

 < 3

37

The in situ covering of the PET non-woven fabric surface with PANI lead to absorption of the EM wave within and on the surface of the covered fabric

[65]

 PET/PPy

In situ polymerization com-dip coating

 < 1

67.08

The in situ covering of the PET non-woven fabric surface with PPy leads to absorption of the EM wave within and on the surface of the covered fabric

[66]

 PET@PPy/Ag

In situ polymerization

0

15.5

The in situ covering of the PET non-woven fabric surface with PPy and Ag leads to absorption of the EM wave within and on the surface of the covered fabric due to enhanced dielectric loss and conductivity

[67]

Vacuum assisted filtration

 Non-woven MXene fabric

Vacuum assisted filtration

-

75

The vacuum-assisted coating of the non-woven fabric with MXene resulted in enhanced EM wave absorption due to enhanced permeableness

[68]

 MXene/CNFs/silver (MCS)

Vacuum assisted filtration

0

50.7

The vacuum-assisted preparation of the non-woven fabric with surface-covered Ag@MXene resulted in enhanced EM wave absorption due to enhanced permeableness

[69]

 MXene/CNF (MC)

Vacuum assisted filtration

0

14.98

The vacuum-assisted preparation of the non-woven fabric with surface-covered MXene resulted in enhanced EM wave absorption due to enhanced permeableness

[69]

 Ti₃C₂T_x @GO@SiO₂ NW PP

Vacuum assisted filtration

-

52.8

Increased interlayer spacing of Ti₃C₂Tx and increased porosity of M/DLCNSs HF-10% successfully enabled numerous EM wave reflection losses to boost EMI SE. This outcome demonstrates once more that electrical conductivity alone is unable to consistently improve the EMI SE for 2D materials

[70]

Sandwiching (layer by layer assembly)

 CNF/Nylon@Ni-Cu

Sandwiching (In situ plating + solution casting + sandwiching)

 ~ 30

63.1

Sandwiching, coating high porosity, and high conductivity of the coatings resulted in absorption-dominated SE due to reflection and conduction loss

[71]

 PET@ Ti₃C₂T_X

Needle-punched nonwoven fabric + spray drying + superimposition of layers

0.12

Specific shielding effectiveness (SSE) to thickness “SSE_t” (891.94 dB/cm²/g)

Sandwiching, high porosity, soft character as well as high conductivity plus Mxenes’ hydrophilicity resulted in absorption-dominated SE

[24]

 Cotton@Ti₃C₂T_X

Needle punched NW fabric + spray drying + superimposition of layers

0.05

SSE_t (2301.95 dB/cm²/g)

Sandwiching, high porosity, soft character as well as high conductivity plus Mxenes’ hydrophilicity resulted in absorption dominated SE

[24]

 Calcium alginate (CA)@ Ti₃C₂T_X

Needle punched nonwoven fabric + spray drying + superimposition of layers

0.09

SSE_t (1735.72 dB/cm²/g)

Sandwiching, high porosity, soft character as well as high conductivity plus Mxenes’ hydrophilicity resulted in absorption dominated SE

[24]

 PET/Cu (MEFTEX 30)

 < 1

58.92

The enhancement in the mass per unit area via a combination of several layers resulted in better SE due to better EM wave(s) absorption

[72]

 CFs/PP/PE (core/sheath) (CEF-NF)

Sandwiching/ lamination

0.48

38.6

Sandwiching, high polarization loss, enhanced ohmic loss due to high conductivity of CFs resulting in absorption dominated SE

[73]

 Poly (2-hydroxyethyl methacrylate) (PHEMA)-CNTs

Cross-stacking ES

-

20.42

In order to stop wave radiation from invading, layers of cloth are used more CNTs. Even at extremely low CNT loading amounts, the CNT-PHEMA has good EMI shielding properties thanks to its distinctive porous cross-stacking aligned structure (0.17 wt. percent)

[74]

 Aramid@Ni/Cu-Fe₃O₄/WPU

Sandwiching (wet-laid protocol) + solution coating

-

34.3

Multiple internal reflections, good impedance matching, good conductivity enhances the shielding process of the aramid NW fabric's having a foam-like structure

[75]

 AF@Cu/Fe₃O₄/WPU

35.4

Multiple internal reflections, good impedance matching, good conductivity enhances the shielding process of the aramid nonwoven fabric's having a foam-like structure

[75]

 AF@Ni/Fe₃O₄/WPU

39.2

Multiple internal reflections, good impedance matching, good conductivity enhances the shielding process of the aramid NW fabric's having a foam-like structure

[75]

Electrospinning

 Poly(L-lactic acid) (PLLA)/Cu

Electrospinning-in situ reductive metal coating

-

32.85

Through the combination of electrospinning and coating, the material was provided with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[76]

 TiO₂/SiO₂@PPy (TSPG-10)

ES + in situ polymerization

 < 2

30

Through the combination of electrospinning and in situ polymerization, the material was provided with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[77]

 PVA@PANI-AuNPs

ES

-

22.99

Enhanced EM waves absorption was achieved via the incorporation of PANI/AuNP which imparted the system with enhanced conductivity as well as dielectric permittivity

[78]

 Nylon@PANI

ES + in situ polymerization

 < 2

40

Through the combination of electrospinning and in situ polymerization, the material was provided with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[79]

 TaC/Fe₃C/C

ES + pyrolysis

32.5

46.4

Through the combination of electrospinning, carbonization, and inclusion of magnetic NPs, provided the material with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[80]

 PAN/W₁₈O₄₉@Ag

ES with or without heat treatment

 < 20

 ~ 100.9

Through the combination of electrospinning, heat treatment, and inclusion of conductive/magnetic NPs, was provided the material with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[81]

 ZrO₂/CF/epoxy (8 layers stacked, 0.72 mm)

ES + carbonization

-7.7

-94

Through the combination of electrospinning, carbonization, and inclusion of magnetic NPs, provided the material with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[82]

 PDMS/MWCNTs/Fe₃O₄@TPU

ES + coating

-

85.4

Through the combination of electrospinning, carbonization, and inclusion of magnetic NPs, provided the material with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[83]

 r-PET/magnetite@SiO₂

ES + dip-coating

0

22

Through the combination of electrospinning, carbonization, and inclusion of magnetic NPs, provided the material with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[84]

 EVA@PDA@Ag

ES + in situ polymerization + electroless coating

0

87

Through the combination of electrospinning, in situ polymerization, and electroless coating of conductive Ag, the material was provided with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[85]

 PAN@SiO₂-4 wt.% Ag-12 h

ES + coating

0

80–82

Through the combination of electrospinning and electroless coating of conductive Ag, the material was provided with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[86]

 TaC/C

ES + carbonization

24.2

37.7

Through the combination of electrospinning, carbonization, and inclusion of magnetic NPs, provided the material with enhanced permeability and conductivity which lead to enhanced EM wave absorption

[50]

Needle punching

 PP/CFs

Fiber blending and needing punching approach

 < 5

42.1

The incorporation of conductive CFs which enhanced the EM wave(s) absorption via its electrical percolation threshold within the shield

[87]

 Polyacrylonitrile PAN-based CFs/sheath/core (PET/stainless steel) (80/20, stainless steel/carbon) fabric

Fiber blending and needing punching approach

-

44.7

The smart amalgamation of PAN based CFs with sheath/core (PET/stainless steel) resulted in enhanced EM wave(s) absorption

[88]

 PP/Zn-Bi

Magnetron sputtering

-

45

Zn-Bi metallization of PP resulted in enhanced EM waves absorption

[89]

 SWNTs/GA-chitosan@PET NW

Spray deposition/coating

7

29

SWCNTs covering of the nonwoven PET resulted in enhanced EM waves absorption via conduction loss

[90]

 Cotton@PDA@Ag

In situ polymerization + electroless deposition + polymer coating

-

112

The coating of the non-woven fabric with Ag resulted in enhanced EM wave absorption due to enhanced multiple internal reflection leading to reflection loss and interfacial polarization within the fabric due to conduction

[91]

 Stainless steel/PET (core/sheath) bicomponent fibers mat (thrice-needle-punched)

Needle punching

22

27

Needle punching impacted the NW fabric with more porous architecture and therefore enhanced permeableness to EM waves leading to more absorption

[92]

 Polysulfonamide (PSA)

Needle punching + coating

-

45.5

Needle punching along with Fe₃O₄ and Ag coating impacted the nonwoven fabric with more porous architecture, magnetic, as well as conductive character and therefore enhanced shielding layer to air impedance matching, and permeableness to EM waves leading to high absorption

[93]

 Carbonized acrylic fibers web

Needle punching + carbonization

0

28.29

Needle punching and carbonization impacted the NW fabric with more porous architecture as conductive character leading to enhanced absorption and permeableness to EM waves

[94]

 Carbonized acrylic mat

Needle punching + carbonization

27.64 for carbonized system at 800 °C

33.7 for carbonized system at 1000 °C

Needle punching and enhanced carbonization impacted the nonwoven fabric with more porous architecture as conductive character leading to enhanced absorption and permeableness to EM waves

[95]

 Carbonized Kevlar mat

Needle punching + carbonization

28.85 for carbonized system at 800 °C

39.73 for carbonized system at 1000 °C

Needle punching and enhanced carbonization impacted the NW fabric with more porous architecture as conductive character leading to enhanced absorption and permeableness to EM waves

[95]

Others

 PP/PE (core/sheet) bicomponent fibers / carbon fibers (CFs) (CEF-NF)

Wet papermaking-thermal-bonding with CFs

 ~ 0

30.29

The incorporation of conductive CFs which enhanced the EM wave(s) absorption via its electrical percolation threshold within the shield

[22]

 CFs mat

Catalytically grown non-woven CFs mat

-

52–81

Conductive nature of the CFs as well as its intrinsic ability to absorb EM waves resulted in enhanced absorption of the waves by the fabric

[96]

 PVDF/VG (Vapor grown)-CNFs

Melt spinning

-

10

[97]