ion icons not wokring in ionic 3

1import {Component} from 'angular2/core';
2import {IONIC_DIRECTIVES} from 'ionic-angular';
3
4@Component({
5    selector: 'my-item',
6    templateUrl: 'build/components/my-item/my-item.html',
7    directives: [IONIC_DIRECTIVES]
8})
9export class MyItemComponent {
10}
11