Map<String, Schema.SObjectType> m = Schema.getGlobalDescribe() ;
Schema.SObjectType s = m.get('Account') ;
Schema.DescribeSObjectResult r = s.getDescribe() ;
String keyPrefix = r.getKeyPrefix();
Map<String, Object> lightningPageRef = new Map<String, Object>{
'type' => 'standard__namedPage',
'attributes' => new Map<String, Object>{
'pageName' => 'home'
}
};
Id typeId = '0ML1l00000001dxGAA';
Messaging.CustomNotification notification = new Messaging.CustomNotification();
notification.setTitle('test title');
notification.setBody('test body');
notification.setSenderId(Userinfo.getUserId());
notification.setNotificationTypeId(typeId );
notification.setTargetPageRef(JSON.serialize(lightningPageRef));
notification.send(new Set<String> { Userinfo.getUserId() });