Supercapacitors　with　high　energy　density,　fast　charging/discharging　rate,　and　long　cycle　life　are　ideal　energy　storage　devices.　A　sufficient　amount　of　the　electrode　materials　is　important　to　obtain　high　energy　density　supercapacitors.　The　poor　electronic　and　ionic　conductivity　are　accompanying　with　increasing　amount　of　electrode　materials,　which　hinder　the　energy　density　and　capacitance　retention　of　supercapacitors　especially　under　high　current　densities.　Long　Ni3Si2　nanoarrays　with　higher　areal　density　and　larger　exposed　surface　areas　have　been　in　situ　grown　on　Ni　foams　as　Ni3Si2　furs　by　low　pressure　chemical　vapor　deposition　to　give　sufficient　amount　of　electrode　materials　with　high　electronic　and　ionic　conductivity.　Atomic　layer　deposition　process　has　then　been　adopted　to　coat　the　Ni3Si2　nanowires　with　different　thick　TiO2,　yielding　Ni3Si2@TiO2　furs.　The　Ni3Si2@TiO2　furs　with　1　nm　TiO2　coating　have　been　demonstrated　to　have　high　supercapacitor　performance.　An　extremely　high　specific　capacitance　as　high　as　7.82　F　cm(-2)　has　been　achieved　by　Ni3Si2@TiO2-1nm　furs　at　a　current　density　of　5　mA　cm(-2).　A　high　areal　capacitance　of　5.91　F　cm(-2)　and　an　excellent　cycling　stability　of　95.6%　retention　after　5000　cycles　at　a　high　current　density　of　100　mA　cm(-2)　have　been　obtained.　The　asymmetric　supercapacitor　assembled　with　Ni3Si2@TiO2-1nm　exhibits　volumetric　energy　density　of　1.528　mWh　cm(-3)　at　a　power　density　of　25　mW　cm(-3)　and　0.93　mWh　cm(-3)　at　0.1　W　cm(-3).　(C)　2020　Elsevier　B.V.　All　rights　reserved.